arthurartmaster
Member
Hi all I have designned a pcb to balance batteries, by using MOSFET's in there linear region (act like resistors). I have designned this circuit to balance 6 batteries the problem I am having at the moment is that, when I apply a voltage across one of the circuits (i.e. C1+ and C2+ of 5V),the other circuits are turning on and I am measuring 5V at the emitter and collector of each of the other optocouplers. However I have not turned on any of the optocouplers there is no voltage across the diodes of the optos. Can anyone please advice. Below are images of the circuits I developed, I have basically repeated the circuit below 6 times in series this image has two of them connected up with a simulation I created is also attached I made in LTSpice. Can anyone else explain why, the top circuit, there is a voltage at the emitter of the circuit, and also why the MOSFET is turning on when there is no voltage across the diode of the OPTO. Thanks Art