A 8.83nW, 0.14ppm/℃ crystal oscillator using duty-cycling automatic amplitude control

IEICE Electronics Express

article

Yulian Wang¹  Xiaoyu Hu¹  Xinxin Ren¹  Heng You¹  Dashan Shi¹  Shushan Qiao¹  Yumei Zhou¹ 

[1] Institute of Microelectronics of Chinese Academy of Science;University of Chinese Academy of Science

关键词: 32-kHz crystal oscillator ,duty cycle ,low power ,RTC;   

DOI  :  10.1587/elex.18.20210275

学科分类：电子、光学、磁材料

来源: Denshi Jouhou Tsuushin Gakkai

【 摘 要 】

This paper presents an ultra-low power 32.768 kHz crystal oscillator circuit for the real-time clock (RTC) generation. A negative feedback amplitude control loop is employed to reduce the oscillation amplitude and the energy loss of the crystal. To further reduce power consumption, the inverting amplifier is powered on periodically by a duty-cycling control pulse, which reduces the static power of the amplifier significantly. Trading off among power consumption, area and design complexity for generating a precise duty cycle pulse, the output square wave of the crystal oscillator circuit is used as the control pulse. The circuit is designed in 55-nm CMOS process with an area of 0.04mm 2 . It shows a power consumption of 8.83nW which cuts the power consumption by 37% comparing with the circuit without pulse control. The proposed circuit achieves a great temperature stability of 0.14ppm/℃ from -40℃ to 100℃ and a power supply sensitivity of 30.5ppm/V over supply voltage of 0.5-0.8V.

【 授权许可】

CC BY