A circuit for detecting a glitch in power supply includes a detection circuit to detect the glitch in a DC supply voltage of the power supply when a magnitude in the glitch in a DC supply voltage of the power supply exceeds a detection threshold, wherein the detection threshold is a function of the DC supply voltage, and wherein the detection circuit comprises a low pass filter, a control circuit coupled to the low pass filter, and a current mirror circuit coupled to the control circuit having an output for providing a logic signal indicative of a detected glitch.