Patent ID: 6278320
Filing Date: 2001-08-21
Classification: G05F

Abstract:
A band-gap filter circuit comprising:an input node connected to an output of a band-gap circuit;an output node;an RC filter, wherein the RC filter comprises:a first resistor connected between the input and output nodes; anda capacitor connected between the output node and a circuit ground;a capacitor charger circuit connected to the RC filter, wherein the capacitor charger circuit comprises:a comparator having a first and a second input terminal, and an output terminal, wherein the first input terminal is connected to the input node and the second input terminal is connected to the output node; anda transistor connected to the output terminal of the comparator and to the RC filter;a current source connected to the transistor, such that the output of the comparator connects to a controlling gate of the transistor and when the transistor is turned on, current from the current source is electrically connected to the RC filter; anda second resistor connected between the input node and the first input terminal of the comparator.