Patent ID: 6995672
Filing Date: 2006-02-07
Classification: B60C

Abstract:
1. An RF transponder comprising: a measurement current source for providing a measurement current to a relaxation oscillator, the relaxation oscillator comprising a measurement switching circuit, a set-reset circuit having a first phase path and a second phase path, and an output, characterized by: a logic circuit; a measurement capacitor disposed in the measurement switching circuit; a first transistor, controlled by the logic circuit, for directing the measurement current to the measurement capacitor for charging the measurement capacitor; and a current mirror having transistors controlled by the logic circuit, for mirroring the measurement current in a second transistor, for discharging the measurement capacitor; wherein the logic circuit provides measurement control signals for combining signals indicative of a phase of the set-reset circuit with signals from a timing generator for controlling alternating charging and discharging of the measurement capacitor according to the phase of the set-reset circuit.