CMOS Temperature Sensor with Ring Oscillator for Mobile DRAM Self-refresh Control

링 오실레이터를 가진 CMOS 온도 센서

  • Kim, Chan-kyung (School of Information and Communication Engineering, Sungkyunkwan University) ;
  • Lee, Jae-Goo (School of Information and Communication Engineering, Sungkyunkwan University) ;
  • Kong, Bai-Sun (School of Information and Communication Engineering, Sungkyunkwan University) ;
  • Jun, Young-Hyun (DRAM Design, Memory Division, Samsung Electronics)
  • 김찬경 (성균관대학교 정보통신공학부 전자전기공학과) ;
  • 이재구 (성균관대학교 정보통신공학부 전자전기공학과) ;
  • 공배선 (성균관대학교 정보통신공학부 전자전기공학과) ;
  • 전영현 (삼성전자)
  • Published : 2006.06.21

Abstract

This paper proposes a novel low-cost CMOS temperature sensor for controlling the self-refresh period of a mobile DRAM. In this temperature sensor, ring oscillators composed of cascaded inverter stages are used to obtain the temperature of the chip. This method is highly area-efficient, simple and easy for IC implementation as compared to traditional temperature sensors based on analog bandgap reference circuits. The proposed CMOS temperature sensor was fabricated with 80 nm 3-metal DRAM process. It occupies a silicon area of only about less than $0.02\;mm^2$ at $10^{\circ}C$ resolution with under 5uW power consumption at 1 sample/s processing rate. This area is about 33% of conventional temperature sensor in mobile DRAM.

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