Patent ID: 6762627
Filing Date: 2004-07-13
Classification: G01R

Abstract:
A peak detector for detecting a peak voltage value of an input signal, comprising:a first switch coupled to receive the input signal and selectively coupling the input signal to an input rectifier, the input rectifier generating a rectified input signal on a first node; a first charge storage device coupled between the first node and a ground node for storing a peak voltage value of the rectified input signal; a second switch coupled between the first node and a second node for selectively coupling the first charge storage device to the second node; a third switch coupled between a reference potential and a second charge storage device for selectively discharging the second charge storage device to the reference potential; a fourth switch coupled between the second charge storage device and the second node; and a third charge storage device coupled between the second node and the ground node, the third charge storage device having a charge storage capability greater than that of the first and second charge storage devices; wherein the first switch and the second switch are alternately closed to sample the input signal and generate an output voltage at the second node indicative of the peak voltage value of the input signal, and wherein the third switch and the fourth switch are alternately closed to decrease the output voltage at the second node.