Hi,
We are using a BQ24610 to implement a LiPoly battery charger, the IC works fine until the battery is fully depleted. To protect the battery pack, we are using a S-8252AAG-M6T1U protection IC from ABLIC. when the IC detects the cells go below 2.8V it will turn OFF the discharge MOSFET to protect the cells from over discharge. SO far so good, the problem comes when AC is reconnected. The charger does not resume the charge, we can see in the scope that the charge perform the detection porcess since we see a 500ms duration pulse in the battery voltage line and also a 125mA current, since we are seeing this pulse during 500ms and the battery voltage goes to 5.8V during this period we assume the charger detects the battery.
This conclusion comes since the algorithm says it will check that the VFB votlage to be below Vrech and if the timer expires it will sucessfully detect the battery. Since we are seeing the full 500ms pulse we assume the timer expires, the problems comes that after detecting a battery connected the charger is not charging at full charge or even at Iprecharge...the question is Why? WE assume that after detecting the battery the charger should go the precharge since the battery is at 5.8V (around 2.9V per cell since is a 2 cell battery pack) which is way below the VlowV of 6.2V (1.55 X 4 = 6.2V... since the voltage divider at VFB has a 1/4 ratio).
Can you explain why the charger is not pre-charging the battery? Does the TTC pin has any influence on the pre-charge process? As far as I understood the precharge is independent and it will work for 30 minutes to charge the battery at a low current so recover the battery and then start the full current charge cycle.
Can the battery detection be disabled? I saw another thread saying that in section 9.3.23 says how to disabled it but it does not say anything...it only explains how it works.
Are we missing something?
Regards
Mark
