0.6–2.0 V, All-CMOS temperature sensor front-end using bulk-driven technology

Abstract

An All-CMOS temperature sensor front-end is designed to work with a supply voltage range of 0.6 to 2.0 volts, and temperature range from 0 to 120°C. The flexibility of 0.6 to 2.0 volt operation was made possible by the use of a bulk-driven op amp. Using all CMOS allows for low voltage and smaller chip area. UMC 0.13μm technology was used for this design. This sensor produces three outputs, two voltages proportional to absolute temperature (PTAT), and one voltage independent of absolute temperature (IOAT). The temperature sensor front-end produces an approximate average reference voltage of 249mV with variation of ±0.7mV, a temperature coefficient of 18.2ppm/°C at VDD = 0.6V to 19.2ppm/°C at VDD = 2.0V, and a voltage coefficient of 290ppm/V at 0°C to 657ppm/V at 120°C. The design produces two linear PTAT voltages with approximate temperature sensitivity of 0.28mV/°C and 0.84mV/°C (Vtemp0 and Vtemp1 respectively) and voltage coefficients of 113.6ppm/V at 0°C, 450ppm/V at 120°C for Vtemp0 and 501.4ppm/V at 0°C, 1904ppm/V at 120°C for Vtemp1. The design has a simulated PSRR of −54dB at 100Hz and 0°C with a supply voltage of 0.6V.