When dc is plugged in board draws 30ma and 12v goes to battery conn m_bat_in for about 2 seconds then drops to 0v. I have changed the charging Ic but still the same. The battery is new

If battery is really 0v (completely drained), it can take quite a while to start drawing current. Leave it plugged in overnight.

Hi I dont mean battery drops to 0v I meat bench supply drops to 0amps bring drawn. Like the circuit is being told to switch off the 12v to the battery for some reason.


When first plugged it it goes from 2ma to 30ma then back to 0ma. Both data and clock on batt connection have 3.3v until the current drops to 0ma then voltage goes from both data and clock to 0v

I have noticed that vcc3m drops to 0v thats why clock and data drop to 0v. U41 generated this and measuring vcc into this its at 20v then it drops to 19.5v that is when vcc3m and vcc5m both go to 0v. both enable signals to u41 are dropping to 0v m_on