Need Help

GopherT

Joined Nov 23, 2012
8,009
It could be a dual op amp but I think there may be something lost in translation from the circuit board to the drawing. The connection to pin #3 is odd no mater what the chip is. That ladder of resistors may connect to ground somehow as a voltage divider.

The relay coil may connect to the positive voltage rail instead of as shown. Please double check all connections.
 

praondevou

Joined Jul 9, 2011
2,942
Did you draw this schematic from a PCB? If so, what's the IC package and what is printed on the IC , if anything?

Pin 2 is floating when the switch is open? Well maybe it has some kind of internal pull-up resistor.

The 39k, 10k resistors are 27k all together, just a simple pullup. doesn't make to much sense putting several in series.

Just simplified your circuit, maybe somebody recognizes it.

 

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