A bandgap voltage reference structure with improved temperature coefficient by eliminating the β effect

The proposed structure utilizes two transistors to generate a PTAT and a CTAT currents, then sums them up according to certain proportion in the surrounding topological structure of the triodes, finally builds the reference current which is temperature-independent and β-independent. The performance has been verified and consolidated through both simulate and tap-out measurement. The temperature coefficient of the fabricated chip is 17.2ppm V/°C during the temperature from -40°C to +120°C. It is proposed to improve the reliability of the CMOS process bandgap voltage reference circuit.