In this paper, a sub 1V bandgap voltage reference (BGR) with Resistive Subdivision in CMOS technology is described. The proposed topology is based on the combination of two elements' voltages of opposite temperature coefficients. By using resistive subdivision methods, maximum input voltage of a p-channel input operational amplifier can be reduced and the problem of sub 1V supply voltage is solved without complex low supply voltage amplifier. Inserting a capacitance Cc to ground at V{sub}(REF) can result in an improvement in power supply rejection ratio. The proposed circuit was verified by spectre simulations, using standard 0.25 μm CMOS process, and the results show that the presented bandgap reference can successfully operate at sub 1V supply and has a temperature coefficient of 25ppm/°C over a temperature range from 0°C to 100°C. The power supply rejection ratio (PSRR) is high at low frequencies, and an added Cc is helpful for PSRR at high frequencies.
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