A Resistive Frequency Locked On-Chip Oscillator with Chopper-Stabilization Techniques

Abstract

This work presents an on-chip oscillator with resistive frequency locked loop and chopper stabilization techniques It can break down the trade-off relationships between power consumption and temperature coefficient (TC) unlike the conventional relaxation oscillator Accordingly resistive frequency locked oscillator (RFLO) can reach a stable TC without losing the energy efficiency With the current-chopper and the offset-chopper operating at different frequencies simultaneously this avoids interfering with the accuracy of the equivalent resistance of the switched capacitor and effectively eliminates the TC issues from the non-idealities Besides it mitigates the low-frequency flicker noise due to the transistors making the better long-term stability It improves nearly ×10 of long-term stability compared with the modes with only one chopper turned on and ×16 of long-term stability compared with the mode with no choppers turned on This work is fabricated by TSMC 180-nm CMOS process It approach a 30 1 ppm/℃ of TC with 2 73 ppm (after 18s integration time) of long-term stability It can generate the output frequency of 200 kHz while consuming only 293 nW the energy efficiency of 1 47 nW/kHz It can operate under a wide-range of supply voltage from 0 9 V to 1 8 V and achieve 0 64 %/V of line sensitivity It can reach 94 14 dB of FoM1 and 89 78 dB of FoM2

Date of Award	2019
Original language	English
Supervisor	Kuang-Wei Cheng (Supervisor)