Patent ID: 7576599
Filing Date: 2009-08-18
Classification: G05F

Abstract:
1. A voltage generating apparatus, comprising: a current source, for generating a first current, a second current, a third current and a fourth current; a first voltage source, coupled to the current source, for generating a first voltage according to the first current, wherein the first voltage has a first negative temperature coefficient; a second voltage source, coupled to the current source, for generating a second voltage according to the third current, wherein the second voltage has a second negative temperature coefficient, and the first negative temperature coefficient is lower than the second negative temperature coefficient; a first differential pair, having a first input terminal, a second input terminal, a common terminal and an output terminal, wherein the first input terminal is coupled to the first voltage, the second input terminal is coupled to the second voltage, and the second current flows through the common terminal; a voltage divider, for receiving and dividing the second voltage, so as to output a third voltage; a second differential pair, having a first input terminal, a second input terminal, a common terminal and an output terminal, wherein the first input terminal is coupled to the third voltage, the second terminal is coupled to the output terminal for outputting a fourth voltage, and the fourth current flows through the common terminal; and a current mirror, having a first terminal and a second terminal, wherein the first terminal is coupled to the output terminal of the first differential pair, and the second terminal is coupled to the output terminal of the second differential pair.