Research And Design Of The Analog Part Of Fully Integrated Temperature Sensor

Compared with the thermistor sensor,integrated circuit temperature sensor possesses obvious advantage, such as higher accuracy, smaller area, lower power consumption, more convenient reading, and it can be used in different environment with various sensor. It also can be applied to circuit and interface of computer. In the system of integrated circuit, it is well used and becomes the development direction in the future.In this paper, a fully integrated low-power digital temperature sensor is presented. Temperature detection circuit and theΣΔmodulator are included. Temperature detection circuit depends on the positive temperature coefficient ofΔVBE that working at different current density of the bipolar transistor, resulting in a voltage proportional to the temperature value, which as aΣΔmodulator input signal, and was converted into a digital bit stream output. The design of the supply voltage is 5V, power consumption is about 0.3mW, the temperature detection range from -75℃to 125℃.The design based on the CMOS process of TSMC 0.5μm2P2M, using Hspice, simulate every modules and the whole circuit, the simulation results show that the circuit design to meet the design requirements.