Other Parts Discussed in Thread: BQ25792
I'm using the BQ25895MRTWR on a custom board. It's taken a while to get to a point where I can continuously monitor the chip regs. I'm now able to monitor every 10 seconds without interfering with chip or overall system operation.
I find that REG12 (ADC conversion of Charge Current) reports what I believe to be an approximately correct reading (around 500mA-600mA). However, it periodically drops to ZERO and then back again. I believe this drop may last several seconds, but I can't be certain. Meanwhile, I believe the actual charge current is pretty stable.
Specifically, I do NOT have an ammeter in the circuit to be able to confirm the instantaneous charge current. But my bench power supply driving the system shows a large change when charging starts (at 12V going from 0.86A to 1.33A), but then NEVER drops below 1.33A even though the REG12 is reading zero charge current.
Is this a known problem? Any suggestions? Below are two example readings of all the chip registers. One has a good reading of 0xC, while the other has a zero reading of 0x0. Note that AllRegs[] has an integer index displayed, so REG12 is AllRegs[18].
(Note that my root problem is that I'm also seeing large fluctuation on REG0E (ADC Conversion of Battery Voltage), even though I believe the current shouldn't be shutting off an on. The combination of both items fluctuating so much is making it extremely difficult for my product to show a meaningful battery voltage icon that *SHOULD* be showing a slowly monitonically increasing percent charge, just like you're used to seeing on your smart phone. Even though this is my root problem, I'm starting my analysis with the Charge Current [erroneously] reporting zero periodically. I don't see a direct correlation between the two, as if it's really dropping current and thus the voltage pushed is falling. That doesn't seem to be the case.)
