A CMOS Temperature Sensor with -0.34°C to 0.27°C Inaccuracy from -30°C to 80°C

With growing applications and increased integration of functionalities on multi-electrode biosensors, more attentions are paid to the need to include on-chip temperature measurement for providing ambient temperature monitoring of bio-samples and for recording heat generated by biosensor chips and their potential damage to bio-samples. This paper presents an integrated temperature sensor design which is intended to provide ambient temperature monitoring in a highly integrated biosensor system. Special attentions were paid to improve power supply rejection (PSR) performance at the clock frequency of 1MHz in the integrated biosensor system using PSR enhanced OTAs. The temperature sensor design was implemented using a commercial 0.18μm CMOS process. The temperature sensor achieves an inaccuracy of -0.34°C to 0.27°C from -30°C to 80°C. At 36°C, the PSR is around -50dB at 1MHz and -89.5dB at DC.