Patent ID: 9714971
Date: 2017-07-25
CPC Classifications: G01R,H01H,H01L,H02J,H03F

Claim:
1. A method for detecting a fault condition of an operational amplifier of an integrated circuit during operation comprising: operating an integrated circuit which includes an operational amplifier (op-amp) having a V+ input, a V− input and an op-amp output and an on-line fault detector electrically coupled to the V+ input and the V− input of the op-amp of the on-line fault detector; monitoring an operation of the op-amp with the on-line fault detector; and developing a fault signal at a fault detector output if the op-amp is in a fault condition as determined by the on-line fault detector; wherein the on-line fault detector comprises an OUTPUT SHORT fault detector coupled to the op-amp output and including a first voltage divider coupled to a first input of a first comparator and a second voltage divider coupled to a first input of a second comparator, wherein a second input of the first comparator and a second input of the second comparator are selectively coupled to the op-amp output, wherein the first comparator provides a first fault signal if the op-amp output is shorted to Vcc, and wherein the second comparator provides a second fault signal if the op-amp output is shorted to ground, whereby a fault signal is applied to the fault detector output upon the occurrence of at least one of the first fault signal and the second fault signal.