Research And Design Of A Monolithic Temperature Sensor

With the development of science and technology, temperature plays a more and more important role. The temperature sensor is widely used in industry, agriculture and other industries. The rapid development of integrated circuit provides a broader platform for the field of temperature sensor,and monolithic, temperature sensor can integrate drive circuit, signal processing circuit and logic control circuit into a IC.The temperature sensor system has the advantages of smaller size, the more functions, high sensitivity, the CMOS process can reduce the cost and power consumption, which provides a broad market for the field of temperature sensor.This paper analyzes the current situation at home and abroad of the temperature sensor, and compares the structure of several temperature sensors, and then design a monolithic temperature sensor,which including bandgap reference circuit,temperature detective circuit and analog-to-digital converter(ADC).The temperature detective circuit is based on the principle which two bipolar transistor biased at different current densities produce△VBE.And then put the detective temperature into successive approximation analog-to-digital converter (SAR ADC),which can process the data.This paper choses CSMC0.35um process.Some important modules have been simulated with Cadence simulation tool Specture. This design can work in the temperature range of-40℃～+150℃and the power supply voltage of2.7V～5.25V. Finally the functional simulation of the whole chip has been done, the results meet the design requirements.