For most of my career developing portable equipment, I've been taught that "less is more." The fewer integrated circuit (IC) devices on a PC board, the better. We've been on a quest for smaller, lighter and cheaper since the first portable computers and mobile phones showed up 20 - 30 years ago. Much of the integration trend, of course, is due to rapid advancements in silicon process technology. I almost hate to admit that I vaguely remember when "submicron technology" was a big deal. Now I can't honestly remember the last time I used an IC that had a feature size anywhere near 1 micron.
I've worked on teams that developed highly integrated PMIC devices for mobile phones over the years, and observed a fairly consistent trend starting with the first digital (2G) products in the 1990s up to the 3G products that became common around 2007 - 2008 or so. The more we could put into the system's PMIC the better - our goal was reduced chip count which equated to lower cost. Even back in 1996 we knew that "someday" the mobile phone would just become a commodity item, so it really needed to be cheap. Of course our ultimate goal back then was to develop the "single-chip mobile phone." I will admit that many of us thought that really meant at least two chips... one analog and one digital... but the story isn't over yet.
People want more power
As engineers, we sometimes forget that everything we do is driven by what our customers (whether individual consumers or corporate customers) are willing to pay for. With the overwhelming boom in mobile technology recently, we know people want high speed data, big bright screens, and the ability to use their devices anywhere and everywhere. So, to enable that, we need power. More power means bigger, higher capacity batteries (of course that leads to the never-ending-quest to get more energy from less space in your battery, but let’s not go there right now).
Bigger batteries mean higher current chargers, and we’ve now gotten to the point in smartphones and tablets that it actually makes sense to “disintegrate” the power conversion solution into multiple components. (This would have practically been heresy back in the good old days.) To that end, some of us former PMIC-guys are working on stand-alone battery chargers again! Fortunately, with the high efficiency chargers, now we can still charge a battery at 2, 3, or even 4 Amp currents and maintain a 1 – 2 mm component height for the power components on the PC board.
NOTE: Each dot on the above chart represents a specific model of phone or tablet.
So, particularly in the field of analog and power conversion circuits, we can't always hold to the mindset that less is more. Sometimes, if you want more (of something), you just need to use more (of something else) to get it. So maybe less is not always more. And maybe “big” is the new “small” when it comes to power.
To read the full post, see Upal's Fully Charged blog on Battery Power Online here: http://www.batterypoweronline.com/main/blogs/less-is-not-more/
Additional references:
- New re-launch of the Battery Management Solutions website.
- Battery management development kits and evaluation modules.
