Patent ID: 7202730

Claim:
A voltage measurement circuit for converting a voltage of a first voltage source connected in series with an offset voltage source to an output voltage, comprising: a first resistor connected to a first terminal of the first voltage source; a first transistor and a second transistor connected as a first current mirror, wherein the first transistor is connected to a second terminal of the first voltage source and the second transistor is connected to the first resistor; a third transistor and a fourth transistor connected as a second current mirror, wherein the third transistor is connected to the first transistor, and the fourth transistor is connected to the second transistor; a fifth transistor connected to the fourth transistor; a second resistor connected between the third transistor and a reference potential; and a third resistor connected between the fifth transistor and the reference potential, wherein an output voltage formed by a current flowing through the third resistor is proportional to the voltage of the first voltage source.