Other Parts Discussed in Thread: BQ25100
Hi everyone!
I'm working on a design using the BQ24088 to charge an internal LiPo battery. We want to implement a simple battery charge percentage tracking algorithm based on the battery's voltage. To do this, we need to be able to manually disable the charger, check the battery voltage "at rest" and then re-enable the charger.
We also wanted to have a PMIC that monitored battery pack temperature for improved safety, thus why we chose the BQ24088 (that and we were able to buy it at the time).
My plan is to connect the TS (temperature sense/NTC thermistor input) pin of the BQ24088 to a 5V-tolerant GPIO on my microcontroller (STM32). Then, when we want to check the "at rest" battery voltage, we can pull the TS pin low, putting the BQ24088 into a temporary, fake "thermal fault", which disables the charger output.
We are using the BQ25100 in another design and the datasheet for this part mentions using the TS pin in this way. I could not find similar recommendations in the BQ24088 datasheet.
I want to confirm with TI that using the TS pin in this way on the BQ24088 will not cause any undesirable/unpredictable behavior. It seems to work fine on the breadboard -- shorting TS to GND disables charger output and removing the short returns the charger to "fast charge" mode.