MP2639A/C Mode Change issue

Dear support,

I bought the EV2639A-R-00A for testing of an application where I would like to automatically switch between charging and discharging by plugging in and unplugging the micro USB connection. I understand that for this to work I will need to control the MODE pin to trigger the charging mode when the USB power/Vin is present. However I have noticed a peculiar behaviour where the CHG LED doesn’t light up when cycling from discharge to charge mode with the MID pin connected to the bottom cell’s voltage. When I remove the connection of the MID pin then the charging works as expected.

When comparing the datasheet between MP2639A and MP2639C, I have noticed a difference in the behaviour of PBDIS, which I assume doesn’t really matter as the discharging behaviour remains the same. However on the Battery Cell Balance and Protection section I noticed that Note 6 which is on the MP2639A datasheet, has been removed for MP2639C. It states that:

NOTE:
6) The balance block is valid only while the charge function is applied. If both the charge and discharge functions are enabled, disable the balance block by connecting MID to GND.

So based on this, can I assume that the reason for the peculiar behaviour that I’ve noticed on EV2639A-R-00A is due to this limitation? Has this issue has been resolved in MP2639C? Can I assume that MP2639C support connection of MID<->bottom cell even when both charging and discharging functions are required?

Hi YH91,

Thanks for your question. I’m looking into this and will get back to you asap.

Thanks,
Cindy

Hi YH91,

Yes, MP2639 version C did resolve most of the issues you addressed, the PB behavior and LEDs malfunctioning have been fixed, as well as the balance function.
There is no mention of version C supporting MID connection to the bottom cells.

Cindy