mshh
Full Member level 6
i tested the attached circuit again but i forgot to connect pin3 ( red circle ) the chip got hot and burnt up for the second time . i don't know why . also i measured the signal on zero ohm resistor it was 8.3 mv the output was .83 volt which mean that the gain is 101 not 51 however gain=1+1000/20 = 51 , i also tried another resistor and i got the same results the output multiplied by 2 ,i tried lm358 and it give the same results.
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