UC San Diego

The development of low power CMOS technology has enabled a higher level of integration for ultra-low power applications. Among the big variety of sensor systems, temperature sensor is one of the most important and commonly used subsystem. In this thesis, a novel architecture of low power temperature sensor is proposed. In order to minimize power consumption, the temperature sensor is designed to work in subthreshold region, with a 0.5V-0.9V supply. With 62nW active power, 0.1⁰C resolution , and 0.55⁰C inaccuracy from 0 to 100⁰C, the proposed temperature sensor achieves low power consumption without degrading resolution and accuracy. The active power is highly reduced by using a novel two-amplifier reference current generator. A 17nW 30-40kHz oscillator is designed as reference clock, 13ppm temperature coefficient is achieved with resistor calibration. The supply voltage sensitivity of oscillation frequency is 1.2%/V without using LDO or regulated current source. To demonstrate the proposed topology, a chip have been designed and submitted for fabrication in 180nm CMOS technology