Patent ID: 7609049
Filing Date: 2009-10-27
Classification: G01R

Abstract:
1. A voltage detection circuit comprising: first and second transistors, gates of the first and second transistors coupled to each other, sources of the first and second transistors coupled to each other, the gate of the first transistor coupled to a drain of the first transistor; a first switch circuit configured for selectively coupling a positive voltage to the sources of the first and second transistors; first and second bipolar transistors, bases of the first and second bipolar transistors coupled to each other, a collector of the first bipolar transistor coupled to the drain of the first transistor, a collector of the second bipolar transistor coupled to a drain of the second transistor; a pair of resistors coupled in series between an emitter of the first bipolar transistor and a negative power, an emitter of the second bipolar transistor coupled to an intermediate node between the pair of resistors, wherein the base of the first bipolar transistor is regarded as a detection voltage input, and the collector of the second bipolar transistor is regarded as a detection result output.