中国邮电高校学报(英文) ›› 2008, Vol. 15 ›› Issue (3): 118-122.doi:

• Microelectronics • 上一篇    下一篇

RS trigger based relaxation oscillator for temperature measurement circuit

邹志革 邹雪城 简文翔 雷鑑铭   

  1. Department of Electronic Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
  • 收稿日期:2007-10-25 修回日期:1900-01-01 出版日期:2008-09-30
  • 通讯作者: 雷鑑铭

RS trigger based relaxation oscillator for temperature measurement circuit

ZOU Zhi-ge, ZOU Xue-cheng, JIAN Wen-xiang, LEI Jian-ming   

  1. Department of Electronic Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
  • Received:2007-10-25 Revised:1900-01-01 Online:2008-09-30

摘要:

Resistance-to-time converter is always used for digital temperature measurement. An reset-set (RS) trigger based, relaxation oscillator based temperature measurement circuit, which is used to convert the change of thermistor sensor into a frequency signal for later processing, has been presented in this article. The RS trigger, which is composed of two inverters designed with distinct logical transition threshold voltages by changing the metal-oxide-semiconductor (MOS) transistor gains, has the same function as the Schmitt trigger in the relaxation oscillator. The advantage of the RS trigger based Schmitt trigger is that it reduces the dependence to supply voltage, chip temperature, and process variation. This temperature measurement circuit has been applied in a clinical thermometer chip that can measure temperature to an accuracy of better than 0.05℃ down to 1.1 V battery voltage. It is fabricated in 0.5 double metal single poly complementary MOS (CMOS) process.

关键词:

;temperature;measurement,;relaxation;oscillator,;RS;trigger,;Schmitt;trigger

Abstract:

Resistance-to-time converter is always used for digital temperature measurement. An reset-set (RS) trigger based, relaxation oscillator based temperature measurement circuit, which is used to convert the change of thermistor sensor into a frequency signal for later processing, has been presented in this article. The RS trigger, which is composed of two inverters designed with distinct logical transition threshold voltages by changing the metal-oxide-semiconductor (MOS) transistor gains, has the same function as the Schmitt trigger in the relaxation oscillator. The advantage of the RS trigger based Schmitt trigger is that it reduces the dependence to supply voltage, chip temperature, and process variation. This temperature measurement circuit has been applied in a clinical thermometer chip that can measure temperature to an accuracy of better than 0.05℃ down to 1.1 V battery voltage. It is fabricated in 0.5 double metal single poly complementary MOS (CMOS) process.

Key words:

temperature measurement;relaxation oscillator;RS trigger;Schmitt trigger