A Bandgap Reference with Low-Temperature Vertex Shift and High-Temperature Unilateral Compensation

A wide-temperature-range and low-temperature-coefficient bandgap reference is proposed in the 0.18 um CMOS process. The output voltage of a conventional bandgap reference is usually in the shape of a parabola with a downward opening. In this paper, the temperature coefficient (TC) can be effectively reduced by moving the parabolic vertex to the low-temperature region so that the output voltage in the low-temperature region tends to be flat, and by adopting a unilateral temperature compensation technique in the high-temperature region so that the output voltage in the high-temperature region is stabilized. The proposed bandgap reference can achieve TC of 1.8 ppm/°C from −50 to 150°C. When the supply voltage changes from 1.6V to 3.6V, the output reference voltage can be stabilized at 877m V with ±3mV maximum error, and the layout area is only 0.01mm2. The simulation results indicate that stable DC bias for analog circuits is provided by the bandgap reference and holds promise for large-scale integration.