Low Voltage, Low Power CMOS Bandgap References

caroline11

Many analog circuits require voltage references, such as A/D and D/A converters. A voltage reference must be, inherently, well-defined and insensitive to temperature, power supply and load variations. The resolution of an A/D or D/A converter is limited by the precision of its reference voltage over the circuit’s supply voltage and operating temperature ranges. The bandgap voltage reference is required to exhibit both high power supply rejection and low temperature coefficient, and is probably the most popular high performance voltage reference used in integrated circuits today. However, IC design is now predominated by low power, low voltage objectives, making CMOS the technology of choice. Since the bandgap reference is bipolar in nature, solutions are required to create the reference without the use of a costly BiCMOS process. This paper examines bandgap references designed for low-power, low voltage operation.