A low power relaxation oscillator with process insensitive auto calibration scheme
In this paper, we present an auto calibrated process insensitive relaxation oscillator. A process sensitivity of 1.36% is achieved by automatically sensing the output clock frequency spread and alternatively adjusting the capacitor used for charging and discharging. In addition, a time to digital converter is adopted for tuning the compensating capacitor. Moreover, the proposed oscillator with on chip calibration scheme, implemented by UMC 0.18mm 1P6M standard process, is validated by our reported extensive post layout simulation results. A frequency of 32.7 kHz can be generated by operating the system under 1V supply voltage.
2016 IEEE Asia Pacific Conference on Circuits and Systems (APCCAS)