Discussion in 'General Electronics Chat' started by mclambert, Apr 3, 2013.
Trying to identify IC.
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.
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.
Does the circuit look right if it is a DIP8 dual op-amp?