How can one implement reverse polarity protection if the 2 cells are put in reverse? If possible, specifics please.
I see the MID on the evaluation board has resistors to protect MID, but hooking up the bottom cell (between GND and MID) up in reverse quickly killed the IC.
Hi Sean,
The FETs should take care of reverse polarity consideration.
The MID pin purpose is more so for cell balancing.
Can you elaborate more on what is meant by killed the IC? Were you able to use the device again?
Possibly the IC halted operation since Vbatt_reg was not met. Please note for this 2cell charger, the Pre-charge threshold is 5.9V. Typical Li-ion is 4.2V fully charged. Due to safety, the charger would either trigger a fault and halt operation depending on the case.
Regards,
Nouman
When I connected the negative end of a cell to PMID and positive to GND, the IC started smoking. This is the eval board I tried this with.
Thank you for elaborating on the situation sean, in this case ot seems the cell balancing path with the lower FET was short circuited. You may have also disturbed the PGND reference for the overall chip (i.e. internal circuitry)
If you do not require the cell balancing feature on the device, you may connect it to AGND.
Regards,
Nouman