One question I frequently get from potential customers is why QuickLogic’s DPO CSSP-based technology ‘will extend your battery life an average of 20-25%’, rather than ‘will extend your battery life 25%’. The difference, of course, is that we state an average savings rather than define a specific savings.
There are a few reasons for this, the two chief of them being
1. Variances in Total System Power Consumption
2. Customer Desire for Visual Enhancement vs Power Savings
3. Variances in Display Quality
Variances in Total System Power Consumption
First, I’ll show a graphic of a number of unique OEM systems that DPO has been tested in, to illustrate how DPO power savings varies.
When we quote power savings, we always quote it at the system level. While the DPO power savings comes directly from the lowering of backlight (LCD/SuperLCD) or the lowering of the average global brightness of the individual pixels (OLED/AMOLED), quoting power savings at only one specific point in a system does not have any meaning to the end user. While it’s great that we save display power, the consumer will simply care about ‘how much longer will my battery last?’, which is a measurement of system power. So, we quote at the system level.
Now, when we quote at the system level, many factors come into play besides simply how much we drop the brightness, most notably the power consumption (read: efficiency) of the rest of the system. You’ll notice in the chart above that there are two different 10.1” tablet systems that our customers have tested. One system consumes 5.7W of power in the test condition, where the other consumes 4.53. As the power consumption varies, the amount we can save as a percentage of that will vary as well.
Customers Desire for Visual Enhancement vs Power Savings
Too much of a good thing is generally a bad thing—and that is applicable to VEE as well. VEE is not simply an on and off algorithm—it is an adjustable technology that is best implemented through calibration. As VEE strength is adjusted in a calibration procedure, our engineers will adjust the display backlight as well for the desired mix of VEE and DPO.
That desired mix can be weighted mostly towards power savings (DPO) or visual enhancement (VEE), or a mixture of both. Our customers determine this, and QuickLogic is happy to accommodate whatever approach they’d like. If the OEM/system designer chooses to concentrate on visual enhancement, they definitely will save power, but it won’t be to the level that a power savings-focused calibration will accomplish. To note: no OEM has ever implemented VEE and DPO without a double digit power savings, no matter how stringent their enhancement requirements are. System designers will save power with any approach.
Variances in Display Quality
As display quality varies, the amount of VEE “strength” needed to restore display content varies as well. A better display may actually require less VEE strength, which likely leads to higher power savings. Further, with a lower-end display, our VEE technology can improve the viewing experience to a much greater level; so much so that we’ve had customers specifically sacrifice power savings for visual experience.