Integrated Bandgap Voltage Reference for High Voltage Vehicle Applications

This work presents a bandgap voltage reference (BGR) integrated in 0.25-mu m bipolar-CMOS-DMOS (BCD) technology. The BGR circuit generates a reference voltage of 1.22V. It is able to withstand large supply voltage variations of vehicle applications from 4.5 V, e.g., in case of cranking, up to 60-V, maximum value in case of emerging 48-V battery systems for hybrid and electrical vehicles. The circuit has an embedded high-voltage (HV) pseudo-regulator block that provides a more stable internal supply rail for a cascaded low-voltage bandgap core. HV MOS are used only in the pre-regulator block thus allowing the design of a BGR with compact size. The proposed architecture permits to withstand large input voltage variations with a temperature drift of a hundred of ppm/degrees C, a line regulation (LR) of few mV/V versus the external supply voltage and a power supply rejection ratio (PSRR) higher than 90 dB