Patent ID: 6628147
Filing Date: 2003-09-30
Classification: H03K

Abstract:
A comparator circuit for determining a time interval in which an input signal changes its amplitude between a first threshold voltage and a second threshold voltage, the comparator circuit comprising:comparator means having a first input terminal receiving the input signal, a second input terminal, and an output terminal; switching means having a first switch input receiving the first threshold voltage, a second switch input receiving the second threshold voltage, wherein the first and second threshold voltages are independent of the input signal, a switch output connected to the second input terminal of the comparator means, and a switch control input, the switching means connecting the first switch input with the switch output upon receipt of a first control signals at the switch control input, and connecting the second switch input with the switch output upon receipt of a second control signal at the switch control input; and control means having a reset input receiving a reset signal, a trigger input connected to the output terminal of the comparator means, and a control output connected to the switch control input, wherein the control means supplies the first control signal to the switch control input upon receipt of the reset signal, and wherein the control means supplies the second control signal to the switch control input upon receipt of one of a rising edge and a falling edge of a signal at the trigger input that is provided by the comparator means.