In part 1 of this series, I discussed the need for external bias and under what conditions you need to consider it. In this installment, I will look at whether you can apply external bias to any controller.

As a rule of thumb, you cannot apply external bias to controllers that have a current limit for the control field-effect transistor (FET) (also known as the high-side FET). It boils down to how the current limit is implemented.

Let’s look at a couple of examples. The first device is the LM3495, an emulated peak-current-mode buck controller. On first glance, it seems feasible that you can apply external bias on the V_IN pin.

Reading through the data sheet, however, there is a section called High-Side Current Limit. A comparator monitors the voltage across the high-side FET when it is on. If the drain-to-source voltage of the high-side FET exceeds 500mV while the FET is on, the LM3495 will immediately enter hiccup mode. A 200ns blanking period after the high-side FET turns on prevents switching transient voltages from tripping the high-side current limit without cause.

Now, how is this voltage across the high-side FET actually monitored? The comparator has two inputs. The first input is the SW pin and the second input is the V_IN pin. The assumption is that the drain of the high-side FET and V_IN pin are always at one potential.

This configuration saves a pin, but it makes the external bias problematic. Let’s say that you apply 5V as the external bias to the V_IN pin. The input voltage is 3.3V, applied to the drain of the high-side FET. This causes a 1.7V difference across the comparator looking for 500mV, so the controller enters hiccup mode.

The next device example is the LM27403. Looking through the data sheet, there is no current sensing for the high-side FET. Thus, you can use this device for supplying external bias to the VDD pin in low V_IN applications.

How did I know to apply the external bias to the VDD pin? Let’s look at the block diagram of the device shown in Figure 1. Take note of the supply voltage shown for the low-side FET drive circuit; in this case, it’s VDD. If you look at the application circuit in Figure 2 you’ll see where CBOOT is connected through the diode. For the LM27403, it is also VDD. Thus, you can determine that VDD is the right pin with which to apply the external bias.

Figure 1: Block diagram showing VDD

Figure 2: Application circuit showing VDD

Now the question is how to determine what value of voltage is OK to apply at the VDD pin. For this, you need to refer to the absolute maximum ratings of the VDD pin and make sure that the external bias applied does not violate this rating. Looking at the LM2403 data sheet, the absolute maximum for VDD is 6V and the recommended operating maximum is 5.5V.

5V is a common rail on boards and would serve as an appropriate bias voltage. The bias voltage needs to be a regulated voltage in order to not violate the absolute maximum ratings of the VDD pin.

In part 3 of this series, I will explore ways to generate your own external bias voltage (in the event that 5V rails are not available) by using charge-pump schemes from the very supply to which you need to supply the external bias.

RS-485 is a standard defining the electrical characteristics of drivers and receivers for use in serial communication systems. It defines not only a single device-to-device interface, but also a communications bus that can form simple networks of multiple devices.

RS-485 runs on twisted-pair cable, and the voltage differential of the two lines defines the logic, as shown in Figure 1. Because of its simplicity, low cost and good noise immunity, RS-485 is widely used in factory automation, building automation and metering applications.

Figure 1: RS-485 network structure

The power supply of an RS-485 device is normally single 5V or 3.3V, and the current consumption is below 200mA. Taking the TI SN65HVD888 as an example, the suggested power-supply voltage is between 4.5V to 5.5V. Many RS-485 networks use isolated bus nodes to prevent the creation of unintended ground loops and their disruptive impact on signal integrity. An isolated bus node typically includes a digital isolator between the bus transceiver and the microcontroller. It also requires an isolated converter to power the SN65HVD888.

The 5V Output, 4,000V Isolated Power Supply Reference Design for RS-485 Applications introduces a high-efficiency, cost-effective circuit for the 5V isolated power requirement. With a 5V to 20V input-voltage range and at least 200mA of output current capability, you can easily implement the circuit in your system board.

The reference design is based on flyback topology using the TPS61046, as shown in Figure 2. The TPS61046 is a 28V output, 900mA switch current boost converter. You can replace it with the TLV61046A small-outline transistor (SOT) package if you prefer.

The transformer supports up to a 4,000V isolation voltage. It has an auxiliary winding to sense the output voltage on the primary side. Ideally, the voltage in the VSEN node is almost the same as in the 5V node; thus, you can regulate the output voltage by regulating the VSEN. The method is called “primary-side regulation.” Compared to the method that senses the voltage directly in the secondary side, the benefit of primary-side regulation is that the optocoupler and reference voltage integrated circuit (IC) are not required, which greatly reduces the solution cost.

Figure 2: A schematic of a primary-side regulation flyback

However, the leakage inductance of a nonideal transformer can cause the output voltage to go out of regulation when the load changes. This leakage inductance is inevitable for a real transformer. Methods to optimize the leakage inductance, such as a better magnetic core or special winding arrangement, will result in increased transformer cost.

The leakage inductance also causes extra current flowing into the VSEN node. As the TPS61046 always regulates the VSEN to the set voltage, the voltage at the 5V node would be out of the 4.5V to 5.5V range required by the transceiver. To solve this problem, introducing a dummy load in the VSEN and 5V nodes absorbs the extra current caused by the leakage inductance. This dummy load is traditionally a fixed-value resistor. However, as the energy of the leakage inductance changes with the real load, the required dummy load should be small at a small real-load condition and large at a large-load condition. But you cannot easily optimize the fixed dummy load to make sure that the output voltage stays within 4.5V to 5.5V if the load varies from 0 to 200mA. Furthermore, the fixed dummy load will greatly reduce the efficiency of the converter in light-load conditions.

The TPS61046 integrates a power-save-mode feature that reduces the switching frequency during light-load conditions to improve efficiency. In heavy-load conditions, the device operates with a constant switching frequency. Using the power-save-mode feature adds a special circuit comprising R4, R5, Q1 and D5 (as shown in Figure 2) to solve to the load regulation problem.

The circuit adjusts the dummy load automatically according to the real load conditions. When the real load is small, the switching frequency and on-time of Q1 are small, so the dummy current is also small. When the real load increases, the switching frequency and on-time of Q1 increase, so the dummy current also increases. This self-adjustable dummy load helps improve load regulation and efficiency. Figures 3 and 4 show the test data in the evaluation board of the reference design.

Figure 3: Load regulation at different input voltages

Figure 4: Efficiency at different input voltages

Beyond the TPS61046, you can use almost all boost converters to build an isolated flyback converter. You just need to select a suitable boost converter based on the input voltage, output voltage and output current, and solution cost.

Additional resources

• Find more boost converters in the DC/DC boost converter selection page.
• Post a question in the TI E2E™ Community Non-Isolated DC/DC forum.
• Download the TPS61046 and TLV61046A data sheets.

An hybrid electric vehicle and electric vehicle (HEV/EV) has various subsystems and critical components working together. Isolated DC/DC converters work similar to how players practice a play from the team playbook, each with their own individual assignments for the greater good of the team.

If you’re a football fan, you probably recognize the similarity between Figure 1 and a play diagram. The design choices and play scheme with isolated DC/DC solutions working together can make a difference in the overall performance of the HEV/EV and determine whether it is a winning EV or not.

Figure 1: A play diagram leading to a successful play – AC input and battery reserves powering HEV/EV subsystems using isolated DC/DC converters

Several blog posts have described HEV/EV powertrain needs, on-board chargers (OBCs) or EV/pile charging systems discussing AC/DC (using the UCC28070-Q1) and high-power isolated DC/DC systems (using the UCC28951-Q1). Other subsystems in the HEV/EV require isolated DC/DC controllers. Isolation is important for dealing with high voltage safely in electrified vehicles, and automotive specifications call for twice the functional isolation. High voltages in hybrids permit size reductions in the combustion engine, which reduce the power required for motion.

Figure 2 highlights some of the basic subsystems found in an HEV/EV; however, not all HEV/EVs are designed this way. This also includes special-purpose vehicles or vehicles with less than four wheels since they also convert stored battery energy to move.

Figure 2: HEV/EV subsystems requiring isolated DC/DC converters

Figure 3 shows an electric bike (e-bike). Special-purpose vehicles would include small task-oriented vehicles (carts, utility task, all-terrain) and personal transportation devices (e-bikes, scooters, wheelchairs, e-rickshaws, even skateboards).

Figure 3: E-bike subsystem requiring isolated DC/DC converters

For subsystems that need regulated and isolated voltages to run those electronics that cannot directly connect to the battery voltage, you’ll need to decide on the best topologies for isolated DC/DC subsystems. Think in terms of scripted isolated DC/DC plays that will result in a score from short distances. You need a list of proven designs and their matchups between the output power and choice of topologies.

For example, the engine control unit (ECU) housing the electronics that control and quarterback an HEV/EV will need a lower DC voltage from the 12 V battery bank. A dedicated flyback design based on the UCC28700-Q1 primary-side regulated flyback controller offers the lowest bill of materials (BOM) and design cost given that the power level is under 50 W. An electrified car’s positive temperature coefficient (PTC) heater module may require isolation from the battery voltage and wide voltage range from the battery; a good choice is the UCC2808A-2Q1 in a push-pull topology, which is a dual interleaved pulse-width modulator (PWM) for several hundreds of watts of power. Motors for pumps, compressors, fans or blowers less than 500 W can use a half-bridge controller when the voltage from the 48 V battery banks need isolation and/or voltage regulation.

You could select the LM25037-Q1 and configure the device as a full-bridge topology for loads greater than 500 W. You can use this same controller in a push-pull topology for a Class A/B audio amplifier that uses both a positive and negative voltage rail for the audio power amplifier. The push-pull topology is also a good choice for driving isolated gate bipolar transistors (IGBTs) used in motor drives or inverters needing positive or negative voltage rails for the gate drive.

An active clamp-forward controller also has its place within the HEV/EV automotive power-management architecture for motorcycle or scooter applications. The controller improves the efficiency of hard-switched topologies. You will have to base your choice of topology on power output, efficiency, cost, BOM, design complexity and area for layout, but in an automotive system you also have to think about temperature ranges, environmental conditions, safety and isolation vs. nonisolated, and input and output voltage ranges. Spending more money on the topology choice to achieve better efficiency may eliminate the need for expensive cooling techniques in the car’s thermal design, and possibly lead to lower overall system cost and improved reliability.

For aftermarket solutions – for example, the premium audio market – nonautomotive components can open up the choice of controllers to cover other topologies; for example, using a simple boost topology for a Class-D audio amplifier design. Every coach needs a full roster of players if they want a winning team.

You could consider the advantages of using a single controller in multiple topologies. The UC2825A-Q1 or UC2856-Q1 are both general-purpose pulse-width modulated (PWM) controllers for use in boost, flyback, forward, push-pull, half-bridge and full-bridge designs.

Table 1 is an automotive isolated DC/DC topology game plan showing winning design choices. I included AC/DC power factor correction (PFC) even though the focus of this post was isolated DC/DC conversion.

 Table 1: Automotive isolated DC/DC end equipment game plan

Table 2 is another viewpoint of the game plan showing general guidelines for DC-DC topology choices given a power range for the design.  

Table 2: Automotive isolated DC/DC topology game plan

What other isolated DC/DC applications do you require in HEV/EV vehicles? Thinking about this topic as a game plan reminds me that I need to check my favorite player stats in preparation for next week’s game.

Learn more about TI’s solutions for hybrid/electric powertrain systems.

In the last couple of years, more and more portal devices such as notebooks and smartphones have employed USB Type-C™ as the interface port. The USB Type-C connector is a totally new USB connector. It has a set of great profile, power rating and data transmission speed improvements. But the most important change about this charging protocol is that USB Type-C introduces a new pin, the configuration channel (CC) pin, to negotiate between different devices.

Legacy adapters use D+/D- lines to perform a handshake between two devices. The most common legacy adapters, as shown in Figure 1, usually have a Type A port as output so that different cables can be match with different phones; for example, an A-uB cable for Android phones, an A-lighting cable for iPhones, etc. USB Type-C also has an A-C cable so that it can be charged by legacy adapters.

Figure 1: A legacy USB adapter

To give users the best usage experience, some USB Type-C product manufacturers have designed their USB Type-C products to support both the new USB Type-C charging protocols via CC as well as existing charging protocols. Employing D+/D- in current USB products, some of the charging protocols cannot be used for USB Type-C connectors (see Section 4.8 of the USB Type-C Cable and Connector Specification, Revision 1.2).

There lies the problem. A USB Type-C connector has an A-C cable to be compatible with legacy adapters and there is an internal pull-up resistor (Rp) inside the USB Type-C plug (see Section 3.5 of the USB Type-C specification) to enable the detection of a USB Type-C device. Once there is a DC voltage existing at V_BUS and the USB Type-C plug is inserted to the USB Type-C device, V_BUS will pull up the voltage level of the CC pin to notify the USB Type-C controller, as shown in Figure 2.

Figure 2: Legacy adapter to a USB Type-C product connection

Even the fast –charging protocols such as QC are not compatible in a USB Type-C connector, the irregular USB Type-C products, as mentioned above, are still going to support these high voltage protocols. In this case, the V_BUS may increase to 9V or 12V after a successful handshake with a legacy adapter via D+/D- lines. This high voltage will be applied to the CC pin of the USB Type-C controller via Rp. Unfortunately, the most common USB Type-C controllers cannot handle such high voltage, because it is out of the USB Type-C specification. To prevent the USB Type-C controller from being damaged in  the case of being tied to VBUS via Rprequires a compliant USB Type-C device.

One simple way to protect the USB Type-C controller is to add a Zener diode between the CC pin of the USB Type-C controller and ground. This Zener diode can clamp the CC line’s voltage within a safe range. But I need to highlight two things:

• The clamping voltage of the Zener diode should be higher than the normal voltage of the CC pin and lower than the maximum rating voltage. But because a Zener diode’s breakdown voltage always varies with its own current (in this case, proportional to the V_BUS voltage) and temperature, selecting a proper Zener diode won’t be easy.
• The current flowing from V_BUS to ground via the Zener diode brings additional losses. This current may be up to several milliamps in the worst case (given that V_BUS may be up to 20V and Rp is lower than 10KOhm ).

Another way to protect the USB Type-C controller is to use a blocking field-effect transistor (FET) , labeled as QB in Figure 3,QB to isolate the USB Type-C controller from V_BUS. The QB is inserted between the USB Type-C receptacle and USB Type-C controller. It can be off when an overvoltage event occurs at the CC pin of the USB Type-C receptacle so that the USB Power Delivery controller does not see such a high voltage. However, this will bring an additional path consisting of a pull-down resistor (RD in figure 3) and its control FET (QD in figure 3). QD will be ON to perform the RD on CC pin in the event of a dead battery. The additional logic circuit for QD may also sacrifice some board space.

A good choice is to adopt a USB Type-C port protection integrated circuit (IC) such as the TPD2S300, which integrates all of the necessary functions for a USB Type-C device. This IC requires no additional protection and logic circuitry. Electrostatic discharge (ESD) protection is integrated as well. Figure 3 shows a typical circuit using the TPD2S300.

Figure 3: TPD2S300 circuit for the CC pin

To protect the USB Type-C devices, such as power banks or smartphones, from irregular adapters or chargers on the market, additional protection for the USB Type-C port is necessary with Zener diodes, blocking FETs or protection ICs.

In the sixth (and most recent) installment of this series, I started the discussion about actuation by highlighting the importance of the delayed trip feature in implementing deadband delays in peak current-mode control with zero software overhead. In this installment, I will explore pulse-width modulation (PWM) valley switching, which is a soft switching technique geared toward scavenging several central processing unit (CPU) cycles, while also improving system efficiency and performance.

In order to understand the cycle scavenging made possible through the valley-switching technique, it is imperative to first learn about the feature itself. Take a look at the flyback converter shown in Figure 1.

Figure 1: Flyback converter

A flyback converter is a simple switch-mode power supply that generates a DC output from either an AC or DC input. In this post, I’ll limit the discussion to the operation of a flyback in discontinuous conduction mode. For operation in this particular mode, the power stage is designed in such a way as to allow the transformer to completely demagnetize during each switching cycle. At the start of the switching period, when the PWM turns on, the primary-side current ramps up from zero. At this stage, energy from the source transfers to the transformer. When enough energy is stored in the transformer, the PWM turns off; current flows to the secondary windings and the stored energy in the transformer is delivered to the load.

Note that the current in the secondary ramps down to zero, completely demagnetizing the transformer during every switching cycle. After the demagnetizing time, there is a delay before the primary-side switch turns on again to start the next switching cycle. This delay during which neither the diode nor the metal-oxide semiconductor field-effect transistor (MOSFET) are conducting is known as dead time or resonant time. During dead time, the interaction between the primary inductance of the transformer and the parasitic capacitance at the switch node generates a resonant ring. This is clearly illustrated in the flyback waveforms shown in Figure 2.

Figure 2: Flyback converter valley-switching waveforms for low loads

Valley switching is a soft switching technique that minimizes switching losses by turning on the PWM for the next switching cycle at a point when the current through the switch is at its minimum. This happens when the resonant rings during dead time for the voltage across the switch are at their valley point. For some applications, it might be best to turn on the PWM at the first valley point, while for others it might be better to wait until the valley point of the third or fourth resonant ring for improved efficiency. Note that resonant oscillations are highly dependent on circuit parasitics and operating conditions, which make it very difficult to detect this optimal valley point.

While this technique traditionally used external valley-switching submodules, that has not been the most ideal solution from a real-time control perspective due to the complex software algorithms required to detect valley points of the resonant rings. The other downside to this approach is the fact that that the submodules can usually only detect the first valley point accurately. This is a major limiting factor for applications where switching at a later valley point instead of the first significantly improves switching efficiency. Adding an external submodule for valley switching also increases bill of materials costs and adds complexity to the overall system, making this approach unfeasible.

C2000™ microcontrollers (MCUs) integrate the valley-switching submodule to provide an on-chip solution that addresses the challenges I’ve mentioned without compromising real-time performance. Enhancements made to type 4 PWM modules allow the latest C2000 MCUs to keep track of the number of resonant rings elapsed so that they can switch the PWM at the optimal valley point instead of limiting themselves to the first valley. This significantly improves efficiency and minimizes switching losses compared to external submodules that can only detect the first valley point.

Moreover, C2000 MCUs scavenge a considerable number of cycles from the main processors by implementing valley switching in hardware with minimal CPU intervention. This gives C2000 MCUs a clear advantage over other general-purpose MCUs that rely heavily on cycle-intensive software algorithms to perform valley switching, burning several CPU cycles in the process.

As you can see, C2000 MCUs bring tremendous value to customers compared to the competition. First, the ability to detect multiple valley points offers a more efficient solution. Second, implementing valley switching in hardware scavenges a significant number of cycles from the main processors, thereby minimizing latencies and improving real-time performance of the system. Third, by integrating the valley switching submodule on-chip, C2000 MCUs also provide significant cost savings and reduce overall system complexity.

Moving on from valley switching, in the next installment I will look at simultaneous writes to PWM registers, as well as one-shot and global reload, that have great potential to scavenge CPU cycles at the actuation stage, enabling C2000 MCUs to improve real-time performance.

Additional resources

• Read the Applied Power Electronics Conference and Exposition (APEC) 2017 paper, “Digital Controller with Integrated Valley Switching Control for Light Load Efficiency and THD Improvements in PFC Converter.”
• Download the technical reference manuals for TMS320F2837xD Dual-Core Delfino™ microcontrollers and TMS320F28004x Piccolo™ microcontrollers.

In my last blog post, I introduced new actuator technology and briefly talked about the need for higher-voltage drivers. In this post, I’ll go into more detail about these high-voltage drivers and four system considerations – waveform synthesis, waveform effects, delay time and actuator placement – that you should keep in mind while implementing quality haptics in your system.

Designers often decide to include haptics in their systems without realizing the number of considerations. You need to design your product around the haptic system – and not vice versa – because haptics is one of the main ways that users interact with their devices. In addition to all the mechanical challenges associated with haptics, the two main decisions you make are choosing the actuator and amplifier. The actuator will be limited by form factor and performance, so I will talk about this later. For this post, I assume you are interested in using linear resonance actuators (LRAs) that you can drive up to 8V or more. TI’s haptic portfolio includes Smart Amps which can provide 8V from a single cell battery, such as the TAS2560 and TAS2557 audio amplifiers. These amplifiers include features such as low-latency startup times, high-efficiency output and superior software support.

Waveform Synthesis

The first consideration to keep in mind when designing your haptic system is waveform synthesis. The synthesized waveform that drives the LRA is crucial in creating a high quality haptic response. To help you with quick prototyping and integration of the amplifier into your haptic configuration, our team created a new application in the PurePath™ Console 3 software. Figure 1 is an example from the TAS2560 application that shows a preview of the waveform generation tool. You can use this tool to fine tune your haptic response based on the LRA. Once the waveform is created, you can export the data and load it into the host processor in your system. The TAS2557 application can generate waveforms in the DSP and does not require exporting the data to the host processor.

Figure 1: TAS2560 waveform synthesizer

Waveform effect

The second consideration for the haptic system is the waveform effect, particularly the frequency and magnitude of the effect. The frequency of the haptic effect will influence the user experience. People perceive low frequencies near 50Hz as a rumble, as opposed to higher frequencies, like 200Hz, which can feel like a crisp buzz. The waveform frequency also affects the rise time of the signal. For example, if you want a waveform to last 10ms and the frequency is 150Hz, you can only drive 1 cycle (equivalent to 1/150Hz or 6.667ms) before applying a half cycle brake signal. An example of a braking signal can be seen in Figure 1 after waveform 1 and before the pause. The brake is applied 180 degrees out of phase from the driving signal and is meant to stop the LRA. After braking, your acceleration profile will be 15-20ms long. If you drove a 200Hz waveform, then you could drive 1.5 cycles and brake for half a cycle for a total waveform time of 10ms. Of course, you need to have an actuator with the respective resonance frequency in order to produce strong acceleration. Short click waveforms are typically <25ms, including the braking portion.

The magnitude of the waveform with previous drivers was limited to the battery voltage. This magnitude can now be boosted up to 8V with TI’s Smart Amp products.

System delay time

The third system topic to consider is the overall system delay time. While timing is important in all systems, it’s especially critical for haptics because it’s related to a good user experience. Figure 2 sums up the delay time for most systems. The three major delays come from the touch sensor, application processor and haptic driver. I recommend keeping the sum of all three delay times near or below 50ms for the best user experience. The driver delay time for the TAS2560 Class-D amplifier is 9-11ms, including the I²C transactions and boost startup time. As the delay time grows, you begin to notice a lag in the tactile response with respect to the touch event.

Figure 2: Signal delay path

Actuator placement

The final system consideration is the placement of the LRA. To optimize the haptic effect when consumers click the soft keys or home button on a smartphone, for example, place the LRA near the bottom of the phone, as shown in Figure 3. LRA placement can become more complicated for wall-mounted designs or tablets with large surfaces. For a wall-mounted application, you’ll need to isolate the surface being touched from the wall mount by using grommets or an isolation layer. You can find an example of an isolated screen design in the Haptic Feedback Capacitive Touch Display Reference Design for Building Automation and Medical Applications. Tablets may require multiple actuators to provide sufficient acceleration across the surface. The actuator placement and waveform effect timing needs to be optimized so that acceleration waves do not cancel each other out.

Figure 3: LRA placement in a smartphone

Figures 4 and 5 show the driving of an actuator using a 5.1Vp haptics driver versus the TAS2560 (8Vp) Class-D audio amplifier, respectively. The drive signal is ~10ms for both figures, but the acceleration for the TAS2560 is 2.5G compared to 1.8G for the haptics driver. That is a 32% increase in acceleration. 

Figure 4: Acceleration profile for the haptics driver

Figure 5: Acceleration profile for the TAS2560 Class-D audio amplifier

There are some significant design considerations before you can start implementing haptics in your design. In your next design, I hope you consider implementing these new LRAs, which are capable of much stronger haptic feedback and can provide a better user experience.

Additional resources

• Download the TAS2560 and TAS2557 data sheets.
• If you have any questions about haptic design visit the TI E2E™ Community Haptics forum.

In part 1 of this series, I discussed the need for an external bias and under what conditions you need to consider one. In part 2, I discussed whether you can apply an external bias to any controller. In this third and final installment, I will go over a circuit that you can use to generate an external bias for any controller. This may prove useful in cases where a 5V bias rail is not available for providing the external bias.

Looking at Figure 1, the shaded region is the external circuit for the bias. Ric represents the current drawn by the integrated circuit (IC).

Figure 1: External bias circuit shown in the shaded box

You must make sure that the external bias circuit can provide the current, since it depends on the operating frequency, selected field-effect transistors (FETs), etc.

Iic = (Qg(Q1) + Qg(Q2))*1e-09*Fsw*1e03                              (1)

Let’s plug in some numbers and use the example of a device running at two different frequencies and using the TI CSD87381P NexFET™ power block. These are the simulation conditions:

• Qg(Q1) = 3.9nC.
• Qg(Q2) = 6.2nC.
• Iic = 12mA at 1,200kHz.
• Iic = 5mA at 500kHz.

Once you figure out Iic, you can calculate Ric for the simulations by Vext_bias/Iic.

Run the simulations with the calculated Ric and make sure that Vext_bias does not exceed the absolute maximum of the VDD pin, or the pin of the IC where you need to apply the external bias. In some cases, you may need a Zener diode or additional loading resistors.

Figures 2 and 3 show the circuit waveforms. You can see that I generated close to 5V for the external bias. As the efficiency curves in part 1 of this series illustrated, this approach helps increase efficency or enables circuits to support higher currents, whatever the case may be.

Figure 2: Waveforms at Fsw = 1,200kHz at Iic = 12mA

Figure 3: Waveforms at Fsw = 500kHz at Iic = 5mA

There are many charge-pump schemes possible with various variants and I have demonstrated a simple method to implement an external bias. One point to note is the variation of the 3.3V rail. If the 3.3V rail has a wide tolerance, I recommend placing a Zener diode to clamp the voltage applied to the VDD pin in case of overshoot on the input voltage rail.

Thank you for reading this series of blogs. I hope you learned when and how to supply an external bias for buck controllers. Feel free to post a comment if you have any questions.

One of the most important factors fueling the automotive infotainment sector is the personal electronics industry. Smartphones, tablets and laptops are just a few of the gadgets that have inspired the design of automotive media interface systems. Trends in the personal electronics market can change so quickly that automakers and Tier-1 suppliers are on the defense to keep up with shorter design cycles than they are otherwise used to in the automotive world.

After the introduction of USB Type-C™ and USB Power Delivery standard for the personal electronics market in 2014, the automotive market had to adapt quickly. There has been a steady increase of USB unit shipments over the past several years – and the market is set for more growth in the years ahead. According to market research firm Strategy Analytics, there will be approximately 23 million USB ports shipped for automotive applications in 2017, growing to more than 25 million units in 2018, the first year automotive USB Type-C will debut in vehicles.

The growth of USBs in vehicles shouldn’t be surprising; consumers care about staying connected in their vehicles. The latest USB connector is the most versatile yet – USB Type-C is high powered (up to 100W), high speed (up to USB 3.1 data rates) and has flip-ability. It’s perfect for personal electronics – and now the automotive experience too.

The anticipated steep increase in automotive USB shipments means that many more areas in a vehicle will have USB ports. USB ports, which are designed into subsystems called media hubs, are usually found in remote places such as an armrest, in front of the gearshift, in glove compartments, or in a rear seat to provide power and data in more convenient locations of a vehicle. These media hubs usually connect to the head unit with a 1-3m cable and can be designed either as a passive or active hub. Which type is best for your infotainment system? Here’s the biggest difference: a passive hub is usually a remote port subsystem with no logic circuitry, while an active media hub uses a hub integrated circuit (IC) or microcontroller (MCU) to program features such as USB On-the-Go (OTG).

There are many benefits to designing a passive media hub instead of an active media hub, including mitigating redundancy and reduced time to market. The reason why it’s a better choice is because many head units already have an MCU or USB hub IC that can control USB OTG functionality. Forgoing an additional digital control on the subsystem reduces unnecessary redundancy. Additionally, jump-starting passive media hub subsystem designs with the help of easy-to-use reference designs makes them simpler and minimizes time to market.

Figure 1 shows a reference design that acts as a passive media hub system connected to the head unit. In the head unit, the USB hub IC takes care of the USB OTG functionality for popular applications such as Apple CarPlay or Android Auto. Active media hubs might have this USB hub IC integrated into the remote media hub subsystem.

This Automotive Passive Media Hub Reference Design with Charging and Enhanced Data Path Performance provides a unique approach for media ports that require data transfers. This reference design shown in Figure 1 provides a flexible, passive solution that allows the system to role swap with a head unit and to charge both USB Type-C and legacy devices with a small 1x2in solution. It can support USB 2.0 through a 15W USB Type-C port.

Figure 1: Passive media hub system block diagram

As consumer demand for supplying power to personal electronics in vehicles continues to increase, so will the number of media hubs. While designing with USB Type-C can be challenging, using TI’s resources to kick-start passive media hub designs will help reduce design time and complexity.

Additional resources

• Learn more about TI’s infotainment and cluster solutions.
• Read more about USB-Type C for automotive applications in the blog post, “One connector to rule them all, or is it?”
• Read more about power-management IC considerations for USB-Type C for automotive applications in the blog post, “Use a dual buck controller in automotive power systems.”

Please join TI at CES 2018 to learn about TI’s SimpleLink™ platform of wired and wireless-connected Arm®-based microcontrollers (MCUs) and network processors. With the rise of connected homes, buildings and factories, TI’s SimpleLink platform provides a seamless, end-to-end solution for streaming sensor data to the cloud.

To demonstrate how the SimpleLink MCU platform, which offers 100 percent application code reuse across wired and wireless MCUs, enables differentiated solutions in home, building and factory automation settings, we’ve put together a complete edge-to-gateway-to-cloud topology.  This topology will be showcased in a single demo in the TI booth at CES but we wanted to share a preview with you in the video below.  

(Please visit the site to view this video)

Our smart automation demo showcases how the SimpleLink MCU platform can be used to develop a range of automation products with a unified software framework and development environment. For example:

• Bluetooth® low energy-connected high-precision motor-condition-monitoring system based on the SimpleLink Bluetooth low energy CC2640R2F wireless MCU and the MSP432P4 host MCU.           
  • High-precision analog motor vibration sensing and ultra-low-power local analytics detect anomalies and help predict failure and maintenance ahead of time.
  • Based on the SimpleLink SDK and sensor and actuator plug-in for reading accelerometer data.
  • Uses the Bluetooth plug-in for the SimpleLink SDK to modularly add Bluetooth connectivity to the MSP432P4 host MCU.
• Bluetooth low energy-connected smart lock with environmentally immune capacitive touch panel:
  • Based on the SimpleLink MSP432P4 paired with the MSP430FR2633 MCU (featuring CapTIvate™ technology) for capacitive touch keypads.
  • Users can control access with their smartphones over Bluetooth low energy or with a keypad using capacitive sensing.
• Various low-power, long-range Sub-1 GHz RF-connected edge nodes will be on display offering long range remote control and monitoring of various sensors and actuators.
  • Based on the SimpleLink CC1310 wireless MCU with integrated Sub-1 GHz RF connectivity.
  • Various sensors and actuators can be made wireless by using the sensor and actuator plug-in for the SimpleLink SDK and the CC1310 wireless MCU, which offers intuitive functional APIs for interfacing with various external sensors typically found in industrial settings for measuring light, temperature and motion.
• Low-power, long-range sub-1 GHz RF-connected temperature sensors.
  • Based on the SimpleLink Sub-1 GHz CC1310 wireless MCU, users can remotely control damper position, or read temperature and humidity sensors.
• Wi-Fi-enabled smart thermostat.
  • Based on the SimpleLink CC3220 wireless MCU with integrated Wi-Fi connectivity.
  • Leverages the SimpleLink graphics library for interfacing with a liquid crystal display (LCD) touch screen for displaying real-time temperature and weather information, while also accepting inputs to change the target temperature of the system.
  • Wi-Fi connectivity interfaces with the cloud to get local weather information using representational state transfer (REST)-ful APIs and to interact with the IBM Watson cloud using Message Queuing Telemetry Transport (MQTT).
• Remote control with cloud connectivity powered by IBM Watson Internet of Things (IoT) platform:
  • Remotely monitor or control a heating, ventilation and air conditioning system from a cloud dashboard created with TI’s graphical user interface (GUI) composer – a graphical what-you-see-is-what-you-get (WYSIWYG) drag-and-drop tool for creating PC-hosted or cloud-hosted GUIs.
• Ethernet-connected gateway with multi-wireless protocols to connect various edge nodes.
  • The control and data streams of the edge nodes are aggregated and sent back to the cloud via a reliable Ethernet connection.
  • Intelligent gateway with smart edge node management and control capability, process sensor data and deploy complex cloud logic at local level.
  • This gateway uses the SimpleLink SDK and various SimpleLink SDK plug-ins to enable Ethernet-connectivity to the cloud, while simultaneously aggregating data from multiple edge nodes that are connected via Bluetooth low energy and Sub-1 GHz.

If you’ll be at CES, come visit the TI booth #N115-117 in the Tech East North Hall. Otherwise, follow us through our various social media channels to stay up to date with the SimpleLink MCU platform: Twitter @TXInstruments, Facebook, Instagram @TXInstruments, LinkedIn and Google +.

Have you seen all of the latest technology that is being integrated into today’s new cars? Well, it’s quite impressive and some of these technologies are even being offered in entry-level and economy vehicles:

• A forward-collision warning with emergency braking system that automatically brakes your car to avoid a rear-end collision in case the car in front of you stops too suddenly.
• An advanced parking guidance system that will automatically back your car perfectly into a parallel parking spot.
• Lane-keeping assist technology vibrates your seat to alert you that you are drifting across the lane; it can even automatically control the steering to ensure that your car remains within the white lines.

New infotainment systems (Figure 1) handle the navigation, music, radio and streaming services inside today’s vehicles. As customers buy more mid-range or entry-level cars, it’s a natural expectation that their infotainment system have a large liquid crystal display (LCD) touchscreen, like on our smartphones and tablets. They also expect their cars to support Bluetooth® and/or Wi-Fi® so that they can stream music, podcasts or news.

Figure 1: Automotive infotainment system

In this post, I’ll discuss several key design considerations for audio amplifiers in new automotive infotainment systems.

Size

Some advanced features need their own dedicated processors and sensors, which are typically located in their own separate electronic control unit (ECU) box mounted behind the dashboard. Space behind the dashboard is very limited, so Tier-1 ECU suppliers are always looking for ways to shrink the footprint of these boxes, including the size of the infotainment head unit (where the radio and audio amplifiers are located) to allow more room for advanced features.

Heat

The addition of new features requires more and more processing power. Higher-performing system-on-chip (SoC) processors run a lot faster and typically consume more power and generate more heat. Likewise, the larger LCD touchscreens in infotainment systems can be affected by the heat generated inside the infotainment head unit box. Therefore, Tier-1 ECU suppliers are looking for ways to reduce the overall thermal load inside infotainment head units.

Tier-1 ECU suppliers have been using Class-AB audio amplifiers inside infotainment head units. However, Class-AB amplifiers are significantly less efficient than newer Class-D amplifier designs (see Figure 2). This is important because the car’s audio amplifier is the second-largest source of heat generation inside the head unit, just after the SoC. The more heat generated inside the head unit’s box means that designers need to include a much larger passive radiated heat sink or a mechanical fan. Both options exacerbate the goal to reduce overall solution size.

Figure 2: Class-AB vs. Class-D efficiency (image courtesy of http://www.audioholics.com)

At the 2018 Consumer Electronics Show (CES), Texas Instruments will be demonstrating the industry’s first 2.1MHz high switching frequency Class-D analog input automotive audio amplifier. We designed the TPA6404-Q1 to best address the issues related to infotainment head unit size and thermal load.

Class-D amplifiers typically switch the amplifier on and off at ~400kHz. A much higher 2.1MHz switching frequency in the TPA6404-Q1 Class-D amplifier design enables the use of a significantly lower inductance value for the output filter. You can see in Figure 3 that a 2.1MHz design using a newer 3.3µH metal alloy-type inductor (as opposed to the much larger 10µH/8.2µH needed for a 400kHz amplifier) allows all eight inductors for a four-channel solution to fit into the same footprint as just one 8.2µH inductor.

Figure 3: Inductor size comparison

Another key feature of the TPA6404-Q1 that helps contribute to a small four-channel amplifier solution size is its “flow-through” audio signal design. Figure 4 illustrates how the analog input signals come into the amplifier device on one side of the chip; then amplification of the audio signal takes place on the opposite side of the device where the signals flow into the external output filters.

Figure 4: Flow-through design of the TPA6404-Q1

Combining metal-alloy 3.3µH inductors along with flow-through design yields the industry’s smallest four-channel automotive Class-D amplifier size. Figure 5 shows that the TPA6404-Q1 complete solution (including amplifier and all required passive components) measures just 4.5cm².

Figure 5: Four-channel Class-D amplifier solution size

If you need to focus on reducing overall solution size and the heat generated in your entry-level infotainment head unit system, then I invite you to learn more details about how the TPA6404-Q1 2.1-MHz Class-D amplifier can significantly help. You can also reduce the development time with the TPA6404-Q1 evaluation module (EVM), as well as the schematics, design files and layout guidance, to kick-start your design.

Additional resources

• Check out the TAS6424-Q1, the digital input companion device to the TPA6404-Q1, and watch a video to learn more about its features.
• Read the blog post, “How switching above the AM band eases automotive Class-D amplifier EMC designs.”
• Explore additional mid-power audio amplifiers to suit your design needs.
• Learn more about TI’s automotive infotainment and cluster solutions.

Our world is becoming much smarter. Across our cities, homes and many aspects of our everyday lives, the increased intelligence going into everyday devices – ranging from thermostats and security systems to cars and even macro systems like our cities’ water or traffic management – is helping create a smarter, more connected world that delivers goods and services in ways that are more efficient than ever.

Millimeter wave (mmWave) technology is a key force in these more intelligent systems, providing crucial sensory information. TI recently introduced a family of mmWave radar sensors that offer highly accurate sensing in a smaller package than existing solutions. TI’s mmWave solutions have won Consumer Electronics Show (CES) Innovation Honoree awards for smart cities, tech for a better world and vehicle intelligence and self-driving technology; Electronic Products’ Product of the Year for sensors and EE Times’ ACE Award for sensors. Because of their small size combined with high accuracy, they are a good fit for a variety of applications, including automotive, robotics, intelligent automation and security, where size, reliability and cost concerns previously forced designers to rely on other solutions. From our cities to our homes to our everyday lives, mmWave technology is enabling a smarter world.

Smart cities

Today’s cities have already made huge leaps in intelligence, but they still have a long way to go to maximize efficiency and productivity. Integrating mmWave technology enables more intelligent resource management and can help ensure that city residents receive goods and services precisely when they need them. As our cars become smarter and move closer to becoming autonomous, a city’s infrastructure must become both smarter and more autonomous as well. This will not only help reduce traffic and congestion but can even help residents find the best parking spots.

(Please visit the site to view this video) 

TI mmWave radar sensors will be a key enabler of this transformation for both cars and the cities they drive in. For example, mmWave radar sensors can help cities reduce water waste by more efficiently managing their water system. These sensors can identify with submillimeter accuracy how much liquid is in a particular tank, thus detecting leaks more quickly and generating precise information about usage. Big data solutions can leverage that information to address leaks, achieve maximum efficiency and reduce waste.

(Please visit the site to view this video) 

Smart homes

Cities are not the only destination for increased intelligence; our homes will also greatly benefit from this increased intelligence and technology. Many of us are outfitting our homes with sensors and smart things, including switches, light bulbs, thermostats and other devices designed to make our homes more automated. It won’t stop with switches and thermostats. Even the way our cars will interact with our homes will become more intelligent, through automated parking and other applications, as mmWave radar sensors help enable the next generation of smart home technology.

For example, mmWave technology in a smart home could increase independence for critical populations like the elderly or disabled. By using radar rather than visual methods to detect and count the number of occupants in a room, mmWave sensors can unobtrusively identify if someone is at home and moving about – or if they’ve possibly fallen and can’t get up, regardless of which room, eliminating privacy concerns.

(Please visit the site to view this video) 

Extrapolated to an office setting, this same technology could help determine how many people are in the office on any given day and adjust the thermostat accordingly. In the event of a disaster, mmWave technology could inform first responders how many people were in the building when the event occurred and may be in need of rescue.

Smart life

Even our everyday lives are becoming smarter. As automation continues to proliferate through factories, offices and many other places, mmWave technology is enabling new ways to interact with the world around us. For example, by being able to detect gestures, we no longer need to take our eyes off the road and reach for the radio dial to change stations or turn up a favorite song. It might even help eliminate the “who has the remote” argument as our TVs begin to recognize our gestures.

(Please visit the site to view this video) 

Our world is getting smarter every day. As technologies like mmWave enable the automation of more and more functions, quality of life will improve as we take advantage of the increased efficiency to spend more time with our families, think more creatively or develop new products.

Medical ultrasound technology has come a long way since the first Somascope. Fashioned from a horse trough and converted radar frame, the instrument fascinated readers of Life magazine in 1954. Its developers – a physician, a radiologist and two electrical engineers at the Denver Veterans Affairs Hospital – had obtained 2-D images of a kidney by submerging one of the engineers in a water bath and sending sound waves echoing through his body with a clunky transducer.

Today, of course, ultrasound is an invaluable medical tool. Harmless and noninvasive, its use of sound waves to visualize biological structures that X-rays can’t detect has a wide variety of applications, including cancer, gynecology, cardiology, physical therapy and vascular medicine. In the six decades since the debut of the Somascope, sonography has drastically improved through both advances in electronics and piezoelectric materials and the integration of Doppler ultrasound, with increasingly sophisticated imaging technology and exponentially faster processing power.

Still, modern ultrasound isn’t perfect. It’s expensive and places large demands on power supplies. Instruments generate interfering noise and produce vast amounts of data that result in less-than-precise images. That’s why our company continues to help make innovative improvements to the technology.

Ultrasound for everyone

Designers can shape the next generation of medical ultrasound scanners with reference designs in the TI Designs reference design library and our integrated circuit portfolio. Recently unveiled reference designs will enable smarter ultrasound scanners that, with fewer components, will be more power-efficient. More precise imaging and an enhanced signal-to-noise ratio help generate higher-quality images and clearer data readings, while cart-based scanners benefit from more compact, low-noise power solutions.

The objective is affordable, compact ultrasound devices capable of producing real-time, high-resolution 3-D images – especially of the heart – for more accurate diagnoses and treatment plans. Some industry observers predict that ultrasound scanners could replace stethoscopes hanging around physicians’ necks – and that’s not far away.

It’s a future in which ultrasound is so widely available that underserved populations worldwide will benefit from improved medical care. That time is approaching fast, and some communities are already benefiting. For example:

• Portable, cart-based ultrasound equipment helped 10 U.S. medical professionals in Mwanza, Tanzania perform surgeries on pediatric patients with anorectal malformations.
• In rural Uganda, access to low-cost, robust ultrasound machines has improved prenatal care by drawing pregnant women to clinics for imaging.
• Technology innovators in Nairobi, Kenya, have developed a wind-up portable Doppler ultrasound machine that doesn’t require any power. The machine also creates a digital readout of a fetus’ heartbeat.
• In Nigeria, a three-year program will train some midwives and healthcare providers to use a handheld machine the size of a smartphone.
• A Netherlands professional soccer team plans to begin using portable ultrasound, which works through a smartphone app and a handheld transducer to assess player injuries on the field.

At upwards of $100,000 for a complete immovable system and around $40,000 for a portable system – that is, any unit not permanently attached to a cart – ultrasound technology is out of reach for many populations.

But one of our company's medical systems architects – Ravindra Munvar in Bangalore, India – says that technological improvements are reducing costs. For instance, as channel count increases to improve the depth and resolution of ultrasound images, the cost per channel has dropped from more than $20 to less than $2. Such developments could push the price point of portable ultrasound as low as $5,000, he said. One vendor is even promising to bring a $2,000 smartphone plug-in probe to market in early 2018.

Power-efficient and more precise

Our company is taking several approaches to address customers’ needs for combining minimal power consumption, miniaturization and low noise with high-quality imaging.

Ravindra explained why improving the power efficiency of medical ultrasound scanners is important. “As the number of channels increases, so does the use of power,” he said. “Our customers are trying to maintain a power budget, so we have a big responsibility to improve power efficiency, especially for portable and handheld systems.” Cooling system requirements are also dependent on power efficiency, he said. Moving parts such as fans can interfere with image precision, so “innovative cooling mechanisms are needed.”

To improve power efficiency for cart-based ultrasound technology, new reference designs from our company enable designers to reduce the size of bulk capacitors, maintain optimized efficiency and minimize power-supply components while maximizing efficiencies in various ultrasound systems.

Our reference designs also cater to the makers of smaller systems. Innovative packaging enables more efficient power use, keeps devices cooler and ensures electromagnetic compatibility. A high level of integration in analog front-end and similar devices means that more electronics can fit inside a probe.

The High-Resolution, High-SNR True Raw Data Conversion Reference Design for Ultrasound CW Doppler addresses key ultrasound design challenges with the industry’s best signal-to-noise ratio, as well as the flexibility to implement digital filtering to further improve signal-to-noise ratio  and resolution. The industry’s lowest noise time-gain compensation makes more precise imaging possible.

With the advent of smart probes that can connect to any processing or display system, wireless features are key.

“Smart probes process most data internally, but if you have to reduce power dissipation, then some of the data processing might need to take place on the display system,” Ravindra said. “Many customers use TI’s WiLink™ devices to achieve this goal.”

What’s next in ultrasound?

Engineers from our company continue to contribute innovations that will enable designers to offer higher-quality ultrasound at reduced price points. To serve populations in the developing world, improvements that contribute to affordability and portability are key. And where backup systems and repair service are unavailable, robustness and reliability are crucial too. Ravindra predicts that the “digital stethoscope that can see inside your body” will become an easy-to-use commodity.

But handheld ultrasound machines won’t make larger machines obsolete. Niche and new applications such as real-time 3-D imaging and elastography will still happen on cart-based systems. And hospitals might prefer to invest in instruments that can’t easily walk away in someone’s pocket.

Soon enough, Ravindra said, the challenge will no longer be to develop smaller, more affordable ultrasound technology. Instead, it will be processing, transferring and storing the massive amounts of data that the ubiquitous instruments produce. Limitations will arise in terms of the number of radiologists and other doctors who can decipher meaningful information from this vast data. However, in the future this will also drive toward more automation in diagnosis and standardization of analysis.

The possibilities are vast, but, more importantly, the impact that our innovations can have on improving the quality of life and saving human lives is significant. See what technology TI has in store for your next ultrasound design.

Given their high performance and integration capabilities, several data center and industrial applications use Xilinx Ultrascale and Ultrascale+ field-programmable gate arrays (FPGAs), including enterprise switches, server FPGA accelerator cards, test and measurement, and space and defense.

Knowing the Xilinx FPGA power specifications for a particular Ultrascale+ FPGA family – Zynq multiprocessor system-on-chip (MPSoC), Virtex, Kintex – requires downloading and using the Xilinx Power Estimator (XPE), as shown in Figure 1.

Figure 1: XPE tool header

Once on the XPE site, you’ll select the settings that correspond to your device family (Zynq Ultrascale+, for example), device part number (such as the XCZU9EG), speed grade, temperature grade and environment (including board size and layers). You’ll then complete the power profile by selecting the clock, logic, input/output (I/O), RAM, digital signal processor (DSP) and transceiver options.

TI has done the pre-work and created a spreadsheet with all Xilinx Ultrascale+ Family variants, their corresponding part numbers, rail names, loading options (choices of clock/logic/I/O, RAM, DSP and transceiver) and voltage and current specifications, as shown in Figure 2.

Today’s automobiles are crammed with more incredible technology than ever. From advanced head-up displays (HUDs) to powered closure systems to theater-quality rear entertainment systems, the quality and quantity of electronic creature comforts has never been greater.

One important system in car – the headlight – is undergoing rapid technological changes. The traditional halogen and xenon light bulbs are being replaced by light-emitting diode (LED) light sources. Furthermore, the advent of adaptive front-lighting system (AFS) and adaptive driving beam (ADB) headlight technology means that the headlight could soon take a big leap forward.

Infused with programmability and high resolution, a new breed of automotive headlight systems featuring leveling and swiveling headlamps, high-end sensors and programmable controllers can do much more than cast bright light in front of a vehicle. With AFS and ADB technologies, the light is not only brighter and sharper – it’s smarter, too.

Imagine that you are driving around a sharp, banked corner on a dark country road in a rainstorm. A typical headlight beam would just illuminate whatever is in front of the vehicle. AFS and ADB technologies let automakers develop more intelligent headlights that can turn with the driver’s view. This means that the light source can more accurately shift to the curving road where illumination is needed, which isn’t always necessarily straight ahead.

Here’s another scenario I’m sure many drivers have encountered. On a two-lane road, the lights from an oncoming vehicle can often be blinding. That’s not the driver’s fault, however. The headlights are incapable of doing anything but shining.

Emerging ADB technologies mean that the headlights of the very near future will be able to change their beam shape, reducing glare for oncoming drivers as well as pedestrians. In other words, the headlights will shine light only where it matters.

So, what’s driving this transition to AFS and ADB solutions? In most cases, it’s coming from automakers realizing that current headlight capabilities are not always delivering what drivers and pedestrians need. Just last year, the Insurance Institute for Highway Safety Highway Loss Data Institute conducted its first-ever headlight ratings, and found that most need improvement.

The technical capabilities of emerging AFS and ADB solutions extend beyond illumination. The flexible form factors of these new headlights will give automotive designers a new palette of creative options in the years to come.

Nevertheless, it’s an exciting time to be at places like TI, where our teams are developing a range of technologies that enable more flexible and powerful headlights for a brighter driving future.

Additional resources:

• Learn more about TI’s innovative analog and embedded processing portfolio that customers can use to design differentiated body electronics and lighting systems for any type of vehicle
• Explore how DLP® technology is used in automotive applications like high-resolution headlights and head-up displays
• Read our blog for more information on DLP technology for high-resolution headlights

The Texas Instruments Foundation has established a philanthropic fellowship program to honor our founders’ long legacy of giving back and leading nonprofit organizations in the community.

Funded by a total of $2.1 million in TI Foundation grants, the TI Founders Leadership Fellows program provides three annual nonprofit work experiences to university or graduate students planning a nonprofit career. The fellowships, designed to build a pipeline of nonprofit leaders in the Dallas area over the next 20 years, were established in collaboration with three local organizations with strong ties to our company’s founders – the Dallas Museum of Art, the University of Texas at Dallas and the United Way of Metropolitan Dallas.

“Our founders created a legacy of deep community involvement and giving back,” said Andy Smith, executive director of the TI Foundation. “That legacy has strongly influenced our culture and has inspired decades of community service by TIers around the world. We want to honor their passion and commitment for making a difference and celebrate the impact their generosity has had on our community.”

Our company’s founders and their families have given tens of millions of dollars to better the lives of people around the world, especially in North Texas, championing education, investing in the arts and helping satisfy basic needs for those who are underserved. The TI Founders Leadership Fellows program is named in honor of Erik Jonsson, Eugene McDermott, Cecil Green and Pat Haggerty.

Our history with the United Way dates back to the early 1960s, when founder J. Erik Jonsson helped oversee the efforts of the American Red Cross and the Community Chest to create what was then called the United Fund. Jonsson was the first chairman of the United Fund board and was instrumental in its growth and direction to take care of the less-fortunate in the community.

In 1961, Jonsson and fellow founders Eugene McDermott and Cecil Green established the Graduate Research Center of the Southwest, later renamed the Southwest Center for Advanced Studies, in Richardson, Texas. Created as a school for students to complete their doctoral work and continue research, the center became part of the University of Texas System in 1969 and was renamed the University of Texas at Dallas (UTD).

Supporting local arts and cultural programs remains a strong part of our philanthropic focus. TI and the TI Foundation have provided generous support to many nonprofit arts groups in Dallas, including the Dallas Museum of Art. Honoring a commitment that started with Eugene and his wife, Margaret McDermott, our company has continued to build on their legacy for more than 50 years by supporting exhibitions, programs and strategic initiatives at the museum.

“Following in the footsteps of our founders, we continue to ensure arts and culture programs remain a part of our community for all to enjoy, and to help make our city a more vibrant place to live and work,” Andy said.

Autonomous cars have gone from being something confined to futuristic sci-fi TV and movies to something we see tested on the roads today. There is still a lot of work to be done before fully autonomous cars are ready for the mass market, but today’s technology is helping cars begin to progress through the Society of Automotive Engineers’ (SAE) levels of autonomy[1].

CES 2018 has showcased many of these technologies this week, and our TI team is highlighting the capabilities of our latest Jacinto™ automotive processors, including our newest Jacinto TDA2P processor family. Here are a few of this year’s “what’s next” highlights from the show floor:

More consumers are considering in-vehicle technologies as a must-have feature when purchasing a car. These technologies not only provide information while driving, like navigation, but they enable both drivers and passengers to seamlessly connect their personal lives to the car through their smartphones, supporting music, hands-free calling and other features.

Recognizing this trend, original equipment manufacturers have started increasing the number of high-resolution displays to integrate these features and multiple domains in the vehicle, including cluster, infotainment and driver monitoring, to provide a seamless, connected user experience.

CES 2018 has featured many of these technologies this week, and our TI team is highlighting the capabilities of our latest Jacinto™ automotive processors, including our newest Jacinto DRA76P processor family. Here are a few of this year’s “what’s next” highlights from the show floor:

Scalable digital cockpit solutions. The DRA76P, DRA746, DRA726 and DRA718 enable you to innovate and scale using a common platform and rich software ecosystem for infotainment, cluster and integrated cockpit solutions.

(Please visit the site to view this video) 

Integrated digital cockpit with 3-D surround view. A reconfigurable digital cluster and head unit leverages the performance and integration of a single Jacinto DRA76P processor to provide a cost-optimized, feature-rich, multi-operating system integrated cockpit. 3-D surround view based on the integrated image signal processor (ISP) enables differentiation with system-level cost savings.

(Please visit the site to view this video) 

Premium reconfigurable digital cluster. A fully reconfigurable digital cluster with next-generation 2.5K display resolution supports rendering at 60fps. The Jacinto DRA76P enables an Automotive Safety Integrity Level (ASIL)-certifiable architecture based on the Arm® Cortex®-M4 running a safety real-time operating system (RTOS), as well as a digital signal processor (DSP)-based driver monitoring and identification system.

(Please visit the site to view this video) 

Low-cost automotive reference design. Build cost-effective infotainment and cluster solutions with a six-layer, DRA718-based automotive-quality design, with features such as radio and audio post-processing.

Automotive gateway reference design. The Jacinto-based Gateway Reference Design TIDA-01425 offers a high throughput that allows for a scalable number of communication interfaces. An optimized hardware design helps reduce time to market.

 Whether your team is developing a digital cockpit solution or an advanced driver assistance systems (ADAS) solution, the TI Jacinto processor family offers a tailored-fit option to provide optimal performance within a best-in-class power budget with cost-saving integration.

Is it easy for you to physically see all of your integrated circuits (ICs) on your printed circuit boards (PCBs), or do you need a magnifying glass to see the small bits of black plastic sprinkled in among the larger resistors, capacitors and inductors? Over the previous few years, passive components – especially power inductors – have gotten smaller and smaller. 1608-sized inductors (1.6mm by 0.8mm) are now common, with rumors that 1005 sizes (1mm by 0.5mm) are coming soon.

These 0603 (60mils by 30mils) and 0402 (40mils by 20mils) sizes often made the ICs, at 2mm by 2mm or 3mm by 3mm, look large in comparison. Not anymore. For those of you designing the latest smartphones, personal electronic accessories and solid state drives (SSDs), the tables have turned. New solutions are available that are 80% smaller.

A 3A step-down (buck) converter (TI’s TPS62088) is achievable in a mere 1.2mm by 0.8mm wafer chip-scale package (WCSP), which is a type of ball-grid array (BGA) package. That’s less than 1mm² of board space for the DC/DC IC. If that’s too small for you, there’s also a 3A step-down converter (the TPS62823) in a larger and more traditional quad flat no-lead (QFN) package, measuring just 2mm by 1.5mm. Both of these power-supply ICs are once again smaller than the power inductors surrounding them, as shown in Figures 1 and 2.

Figure 1: A 3A DC/DC is smaller than a 1608-size resistor

Figure 2: A 3A DC/DC is smaller than a 2016-size inductor

Is this still too big, you say? Although the above solutions are truly small for 3A devices, they offer much more power than what the smallest systems need, such as wearables. For these, 1A of output current is more than enough for any rail in the system. If you just need an amp or less, the TPS62801 shown in Figure 3 checks in at a mere 1.05mm by 0.7mm – not quite as small as a 1005-size component, but smaller than any 1A power supply on the market.

Figure 3: A 1A DC/DC is almost as small as a 1005-size capacitor

So what’s the secret behind these smallest DC/DCs? Quite simply, a high switching frequency and a stellar silicon process. The three DC/DCs described here switch between 2.4MHz and 4MHz, which enables you to use either 0.24µH or 0.47µH inductors. With fewer physical turns of wire required on the inductor’s core to generate this very low inductance, physics says that it is easier to make the inductor smaller.

Of course, I can’t go into details as to what makes the power-optimized process so innovative; I’ll just let the results speak for themselves. The internal power transistors have both very low resistance and very low gate charge to produce high efficiencies at high currents, while switching at very high frequencies. Furthermore, the low quiescent current (I_Q) of 5µA or less sustains the high efficiency down to very light loads.

Figure 4 shows that the efficiency for a common 5V_IN to 3.3V_OUT converter is still very high at 93% even at its full 3A load, with a peak of 95% at a 1A load. Near 90% efficiency is maintained at a very light 100µA load. There is no efficiency degradation, even while operating at 4MHz. Such high efficiency results in longer battery life for portable systems and a lower temperature rise for both portable and stationary systems.

Figure 4: TPS62088 efficiency is over 90% across the entire load range

In your system, where do you need the smallest DC/DCs?

Additional resources

• Check out these blog posts:
  • “A super-small, high-efficiency PMOLED reference design for wearables.”
  • “How small is small?”
  • Order samples and evaluations modules (EVMs) for the TPS62088, TPS62823 and TPS62801.