Method for performing a tri-state comparison of two input signals in a window comparator circuit, and window comparator circuit for implementing the method

Abstract

A method performs a comparison of input signals in a window comparator circuit. In a first phase, input, ground and offset voltages are stored on capacitors. A comparison is performed between a first adapted input voltage and a second adapted input voltage added to an adapted offset voltage, to provide a first output signal. In a second phase, the voltages are stored on the capacitors in a different manner. A comparison is performed between the first adapted input voltage added to the adapted offset voltage and the second adapted input voltage, to provide a second output signal. Finally, a control of the state of the output signals is performed to determine if the comparison is in a low or high state if the output signals have a same low or high output level, or in an intermediate state if the output signals have a different output level.