Low voltage, band gap reference

US6307426A · kind A · utility

Assignee

• SGS-Thomson Microelectronics S.A. · IT

Inventors

• Giulio Ricotti · Pavia, IT
• Domenico Rossi · Mortara, IT

Key dates

• Filing date: Sep 3, 1996
• Grant date: Oct 23, 2001
• Expiry date: Sep 3, 2016

Classification

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

Abstract

A voltage, replica of the difference between two dissimilar base-emitter voltages in the form of an intrinsic input offset voltage of a differential input pair of transistors of a noninverting, buffer-configured operational amplifier, is summed with a pre-established fraction of a base-emitter voltage, to produce a voltage reference without thermal drift of a level that can be as low as few 10 mV. The intrinsic input offset voltage is controlled by a local feedback loop acting on the bias current that is forced through the input pair of transistors that may be realized with a certain area ratio. The relatively simple circuit is useful in battery operated, low supply voltage, systems.