An On-Chip Relaxation Oscillator With Comparator Delay Compensation

摘要

In this brief, a relaxation oscillator with comparator delay compensation is presented. Two digital compensation loops are introduced to compensate for the comparator delay. This relaxation oscillator is fabricated in the 0.18-mu m CMOS process. The measured average oscillation frequency is 943.1 kHz. The whole oscillator consumes 5.2 mu W under a 0.9-V supply. The measured average temperature coefficients (TCs) of the oscillation frequency with and without compensation are 93.88 and 618.17 ppm/degrees C, respectively. It achieves a TC improvement of 6.6x. The measured frequency variation is within +/- 0.7% from -10 degrees C to 100 degrees C by using the DCLs. The measured line sensitivity is 4.37%/V. The measured figure of merit (FOM2) is 173.3 dB.