Absolute value peak differential voltage detector circuit and method

• Main Authors: PARASCHOU MILAM, RABE ROBERT L
• Format: Patent
• Language: English
• Published: 10.04.2008
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHICCOMMUNICATION

A peak voltage detector is used to detect the absolute value of the peak differential amplitude of a differential input signal. The peak voltage detector includes a differential amplifier receiving the differential input signal and generating a corresponding pair of differential output signals. The voltage detector also includes a capacitor on which an output signal is generated. A first differential comparator generates a first signal whenever the differential voltage from the differential amplifier is greater than the voltage of the output signal. A second differential comparator generates a second signal whenever the negative of the differential voltage from the differential amplifier is greater than the voltage of the output signal. A current source applies current to the capacitor responsive to receiving either the first or second signal. The amplitude of the feedback voltage is thus equal to the absolute value of the peak differential amplitude of the input signal.