Hello everyone,

I have made a schematic (circuit) (attached as jpg) following layout on the PCB board that I found in battery charger device.
Don't know if I have done a good job and is this circuit made correctly.
It looks like a MOSFET drive circuit, but can not understand the function.
I would like to learn and understand function of this circuit.
It would be really great when someone can explain me how does this circuit works and diodes (D1, D2, D3), which type of diodes are they, MELF package, marked with a blue band, Vf = cca. 0,20V.

Thanks in advance.

 

Welcome to AAC!

Is this something you drew? Or a design you copied from somewhere? It has a number of problems.

There are no component values, ground connections are missing for TR2 and TR3, R6 is shorted.

I removed a lot of white space to make the schematic easier to read.

 

Hi Dennis,
I have a PCB board that I took out from a battery charger device. I tried to make a schematic just following a layout.
I would like to understand how does it work. I know some types of MOSFET/IGBT gate drive circuits, but this one looks strange.
Battery charger output is Vout=24VDC, Iout=60A.
Component values can give you on Wednesday. Must check out the connections form TR2 and TR3, and tat part with a R6.
There are some diodes, MELF, (D1, D2, D4), they are burned. Would like to replace them and try to repair device.

 

I tried to make a schematic just following a layout.

Trace the circuit again and verify the connections I circled. TR2 and 3 should have a ground connection on the source.

 

Best option is to take pictures of the PCB both sides , good close up focused , then we can see where your circuit is wrong..

 

Sorry, there are more mistakes in that first circuit. I made a new one, tracing layout. I took values as well.

 

like for keeping attempting what you do - circuit reading from PCB is a tedious task