Patent Number: 7,786,790

Title: Temperature compensation circuit

Abstract: A temperature compensation circuit performing temperature compensation of an analog reference voltage, includes: a first reference voltage generating circuit generating a first voltage of which a voltage level varies depending on a temperature; a second reference voltage generating circuit generating a second voltage of which a voltage level is independent of a temperature and having a circuit configuration that is same as a circuit configuration of the first reference voltage generating circuit; an inverting amplifier having a gain of 1, which inverts and amplifies a voltage difference between the first voltage and the second voltage so as to generate a third voltage; and a differential amplifier amplifying a voltage difference between the third voltage and the first voltage so as to generate a fourth voltage In the temperature compensation circuit, the differential amplifier includes: a first operational amplifier; a first resistor coupled between a first node and a second node that is an inverting input terminal of the first operational amplifier; a second resistor coupled between a third node and a fourth node that is a non-inverting input terminal of the first operational amplifier; a third resistor coupled between the second node and a fifth node that is an output node of the first operational amplifier; and a fourth resistor coupled between the fourth node and a sixth node to which an analog reference voltage is applied. Further, in the circuit, resistance values of the first resistor and the second resistor are set to be same as each other, and resistance values of the third resistor and the fourth resistor are set to be same as each other.

Inventors: Yoshida; Naoki (Suwa, JP), Kanai; Masahiro (Suwa, JP), Kobayashi; Asami (Fujimi-machi, JP)

Assignee: Seiko Epson Corporation

International Classification: H01L 35/00 (20060101)

Expiration Date: 8/31/12018