Patent ID: 7564225

Claim:
A circuit for generating a stable reference voltage, the circuit comprising: a first resistor having a first terminal and a second terminal; a second resistor having a first terminal and a second terminal, the first terminal of the first resistor being coupled to the second terminal of the second resistor; a transconductance amplifier having a negative input terminal coupled to the first terminal of the first resistor, and a positive input terminal coupled to the second terminal of the first resistor, wherein the transconductance amplifier is configured to establish a threshold voltage difference between first and second input transistors across the first resistor; a gain stage to amplify the threshold voltage difference between the first and second transistors; and a power transistor having a gate terminal and a drain terminal, the power transistor configured to receive the amplified threshold voltage difference through the gate terminal and send a feedback signal from the drain terminal to the negative input terminal of the transconductance amplifier through the second resistor.