This application is for a satellite battery power system. Some hundreds will be made. The MP2642 was chosen because of the desire to use US content.
There are 5 Samsung INR21700-50E cells series connected to the EVL2642-R-00A per step 1 on the EVL2642-R-00A data sheet. The cell voltages are:
Cell 1: 4.065V
Cell 2:4.166V
Cell 3:4.026V
Cell 4:4.204V
Cell 5:4.076V
The only 4 jumpers on the board are the ones connecting Enables 1-4 to S1-4.
I would like to balance cell 3.
For the following tests the MCU_ground pins were connected to the - of a 3.3V power supply and the MCU_Vcc pins were connected to the + of the 3.3V power supply.
Attempting boosting from cell 2 to cell 3 by putting 3.3V on MCU_EN2 and MCU_Mode2 does not cause any current flow into cell 3.
Attempting bucking from cell 4 to cell 3 by putting 3.3V on MCU_EN3 and all MCU_mode pins disconnected does not cause any current to flow into cell 3.
What is wrong with my procedure and what is the right way to balance cell 3?
I have verified all the connections to the board. The battery string voltages are applied correctly to the cell pins. A second board was also tried with the same results.
Thank you for your help.
Bill Schlanger
EV Enterprises
Bill@eventerprises.biz