Low supply voltage bandgap reference circuit and method

US9086706B2 · kind B2 · utility

Assignee

• Hong Kong Applied Science and Technology Research Institute Company Limited · CN

Inventors

• Chi Fung Lok
• Le Shen · Beijing, CN

Key dates

• Filing date: Mar 4, 2013
• Grant date: Jul 21, 2015
• Expiry date: Dec 12, 2033

Classification

• Technology area (CPC G): Physics
• CPC primary: G05F3/30
• WIPO field: Control
• WIPO sector: Instruments

Abstract

A circuit and method for a bandgap voltage reference operating at 1 volt or below is disclosed, wherein the operational amplifier (A1) drives resistors (R2, R3) only so that both the flicker noise contribution and the process sensitivity due to the conventional metal oxide semiconductor (MOS) devices used as a current mirror within the proportional-to-absolute-temperature (PTAT) loop are eliminated. Two symmetric resistive divider pairs formed by (R1A/R1B, R2A/R2B) are inserted to scale down both the base-emitter voltages (VEB1, VEB2) of bipolar transistors (Q1, Q2) and the PTAT current (IPTAT) so that an output reference voltage (VREF) becomes scalable. Proper bias currents through transistors (M3, M4), which are used to bias (Q1, Q2) and (R1A/R1B, R2A/R2B) respectively, are produced by an additional V-I converter (319) using VREF itself, resulting in a final process, voltage and temperature (PVT) insensitive output reference voltage.