Patent ID: 8648580
Filing Date: 2014-02-11
Classification: G05F

Abstract:
1. A regulator for providing a low dropout voltage at an output node of the regulator, comprising: a core circuit, comprising: an amplifier having a non-inverting input terminal for receiving an input voltage, an inverting input terminal, and an output terminal; a first resistor coupled between a ground and the inverting input terminal of the amplifier; a second resistor having a first terminal coupled to the inverting input terminal of the amplifier and a second terminal; and a basic unit, comprising: a first transistor coupled between a first voltage source and the second terminal of the second resistor, having a gate; a first current source coupled between the first voltage source and the gate of the first transistor, providing a bias current; a second transistor, having a first terminal coupled to the second terminal of the second resistor, a gate coupled to the output terminal of the amplifier and a second terminal, wherein the first and second transistors are different type MOS transistors; and a first current mirror, coupled to a second voltage source, the first current source and the second terminal of the second transistor; and at least one replica unit, generating the low dropout voltage according to a voltage of the output terminal of the amplifier, wherein a voltage level of the low dropout voltage is determined according to the input voltage and a ratio of the second resistor to the first resistor.