A 1.74 ppm/°C, high PSRR bandgap reference with fast start-up

A novel BiCMOS bandgap reference (BGR) with low temperature coefficient (TC), high power supply rejection ratio (PSRR) and fast start-up is presented in this paper. Utilizing the currents´ temperature characteristics of BJTs in active region and MOS FETs in subthreshold region, the temperature drift of the proposed BGR is greatly reduced in full temperature range. This method focuses on achieving several points with zero TC on the curve of reference voltage instead of single valley or peak in the whole temperature range. Besides, clamping operational amplifier is designed not only to stabilize the loop, but also to reduce the start-up time. The proposed BGR is implemented with 0.6-μm BCD technology, and is validated with Hspice in a temperature range of -45°C ~ 125°C. Simulation results demonstrate that a TC of 1.74ppm/°C is realized, and a PSRR of 87dB is achieved. The start-up time of the proposed BGR is only 8us at room temperature.