Design Of Voltage Reference On Low Supply

Bandgap voltage reference(BGR) is currently the voltage reference most widely used in integrated circuits, and it's technology is matured, a typical BGR has been able to achieved low temperature coefficient and high stability. But in the current, the supply voltage of BGR is generally greater than 1.25V and the output voltage is fixed. With the development of Large Scale Integrated circuit(LSI) and the decrease of Technology Dimension, the supply voltage of circuit getting lower and lower, and the reference voltage that different from the typical bandgap voltage is also often used in circuit. Therefore, it is need to study the new structure of voltage reference that can meet advanced technology and has a non-standard output voltage.This paper focusing on the main problems meet in low supply voltage reference design, and do a research on low supply voltage design techniques, power supply noise rejection(PSR) performance, low power, compensation and amplifier design, the main work and research results are as follows:(1). Proposed a voltage reference of new method for low supply voltage, and designd a voltage reference which can work at 0.5V supply voltage, by adjusting the device parameters, the output voltage can be any value from 0 to VDD, the total power consumption of the circuit is only 0.65μW.(2). Power supply rejection ratio (PSRR) is one of the most important indicator of voltage reference, it reflects the affection of power supply noise to output voltage. This paper presents a structure which can improve the intermediate PSRR of voltage reference, and verified the feasibility of the structure, this structure can be mixed use with other circuits of PSR improve, in the mixed experiment, the low-frequency PSRR reached -164dB, PSRR in the whole band is no higher than -53dB.(3). Some low-supply voltage reference required amplifier which have wide input common-mode range, a low supply voltage Rail-to-Rail Constant gain amplifier which based on dynamic bias method has been carried out, and a curcuit has been designed. Experiment show that when the input common mode voltage changes from 0V to the supply voltage, the variation of amplifier's gain is less than 1.5dB.