Survey of Bandgap and Non-bandgap based Voltage Reference Techniques

Abstract

Abstract. The design challenges of voltage reference generators in CMOS technology have increased over the years in low-voltage low-power CMOS integrated circuits, constituting analog, digital, and mixed-signal modules. The emergence of hand-held power autonomous devices pushes the power consumption limit to nW regime. Along with these confrontations, limited full-scale range of data converters at low supply levels demands accurate reference voltage generators. This paper reviews the allied design challenges and discusses the evolved methodologies to tackle them. This paper also prominently surveys the sub-1 V voltage reference topologies presented in the literature along with classic bandgap based voltage reference topologies. Non-bandgap (only CMOS) based reference architectures are proven to be area-and power-e cient, but always have to be accompanied with auxiliary on/o chip trimming mechanism for high accuracy. We also provide insightful analysis of the voltage reference topologies required by the designers.

A 10.5 ppm/°C Modified Sub-1 V Bandgap in 28 nm CMOS Technology with Only Two Operating Points

“…Still, they did not improve TC much, especially since the systematic offset of BGR was not addressed. A. J. Annema et al [12] proposed a bandgap with a resistive divider at the input of the opamp so that the opamp experiences a very low common mode at a high temperature to improve performance [16]. Unfortunately, this technique increases the mismatch due to additional potential division.…”

-81dB PSRR regulated cascode fully MOS bandgap reference for power management in RF energy harvesting systems

“…As such, some modern bandgaps have moved to sub-1V architectures such as [6] that can scale down the reference voltage by means of resistor ratio whenever needed and can support lower supply voltages. An ideal bandgap circuit should have a good temperature coefficient, high PSRR and good accuracy [7]. However, achieving all the mentioned specifications will possibly incur tradeoffs in terms of minimum supply voltage, area, power consumption or output swing among other things.…”