低功耗智能便携式温度测量仪研究报告翻译.doc

An ultra-low-power CMOS temperature sensor for RFID applications Abstract: An ultra-low-power CMOS temperature sensor with analog-to-digital readout circuitry for RFID applications was implemented in a 0.18m CMOS process. To achieve ultra-low power consumption, an error model is proposed and the corresponding novel temperature sensor front-end with a new double-measure method is presented .Analog-to-digital conversion is accomplished by a sigma-delta converter. The complete system consumes only 26A @ 1.8 V for continuous operation and achieves an accuracy of ±0.65?C from –20 to 120?C after calibration at one temperature. Key words: CMOS temperature sensor; error analysis; digital output; low power; RFID DOI: 10.1088/1674-4926/30/4/045003 EEACC: 1205; 1065H 1. Introduction RFID technology has attracted profound attention. Not content with object identification only, people are seeking for more functions provided by RFID systems. One of the most at tractive applications is to realize real-time temperature sensing by integrating a temperature sensor into the RFID tag. However, there exist some challenging features for the sensor. First, the temperature sensor must be on-chip and easy to calibrate to minimize the cost. Second, the power consumption of the sensor is stringently limited. Third, the temperature sensor should achieve high accuracy in the whole temperature sensing range. Several papers have reported temperature sensor designs. However, these can either not be realized in low-cost CMOS technology or they consume too much power for continuous operation. In this paper, a novel design of a CMOS temperature sensor, which offers low power, low cost and high accuracy, is proposed. An error model for this sensor is developed. Also, the architectural improvements of the temperature sensor, which includes a sensor front end and a sigma-delta ADC, is given. 2. Error model The most important candidate for a CMOS temperature sensor is the bipolar transistor, which c