Voltage

Engineering

Curvature

Common emitter

Materials science

Operational amplifier

Bipolar junction transistor

Amplifier

Computer science

Line regulation

Transistor

Bandgap voltage reference

Offset (computer science)

Mathematics

Voltage reference

Electronic engineering

Geometry

Dropout voltage

Silicon bandgap temperature sensor

Programming language

Input offset voltage

CMOS

Optoelectronics

Electrical engineering

IEEE Journal of Solid-State Circuits

This article introduces an accurate current-mode bandgap reference circuit design with a novel shared offset compensation scheme for its internal amplifiers. This bandgap circuit has been designed to operate over a very wide temperature range from -40 °C to 150 °C. Its output voltage is 1.16 V with a 3.3-V supply voltage. A multi-section curvature compensation method alleviates the error from the bipolar junction transistor's base-emitter nonlinear voltage dependence on temperature. The bandgap reference circuit contains two operational amplifiers that are utilized to generate proportional-to-absolute-temperature (PTAT) and complementary-to-absolute-temperature (CTAT) current sources. With the implementation of the described shared offset-cancellation methodology, the simulated output inaccuracy introduced by the amplifier is kept to a 5σ offset within ±4.6 μV while allowing to conserve die size and power consumption by preventing that each amplifier is accompanied by its own active auxiliary offset-cancellation circuit. Designed and fabricated in a 130-nm CMOS process technology, the bandgap reference has a measured output voltage shift of less than 1 mV over a -40 °C to 150 °C temperature range and an overall variation of ±8.2 mV across seven measured samples without trimming.

A 1.16-V 5.8-to-13.5-ppm/°C Curvature-Compensated CMOS Bandgap Reference Circuit With a Shared Offset-Cancellation Method for Internal Amplifiers