Patent ID: 8269527
Filing Date: 2012-09-18
Classification: H03K

Abstract:
1. A hysteresis comparator circuit that compares first and second input signals to output a hysteresis output signal, the hysteresis comparator circuit comprising: a constant current source including a load resistor to generate a given constant current; a first comparator controlled by the constant current supplied from the constant current source to compare the first and second input signals to output a first comparison result, the first comparator including: a second comparator controlled by the constant current supplied from the constant current source to compare the first and second input signals to output a second comparison result, the second comparator including: an output circuit having a pair of inputs thereof connected to the first and second comparators, respectively, which inverts an output thereof in response to each of the first and second comparison results to generate the hysteresis output signal, wherein the constant current source supplies the constant current to both the first comparator and the second comparator, and wherein a ratio between the constant current generated by the constant current source and a first current flowing through the first differential resistor of the first comparator, as well as a ratio between the constant current and a second current flowing through the second differential resistor of the second comparator, is dependent on the resistance value of the load resistor of the constant current source.