Relaxation oscillator calibration technique with comparator delay regulation

摘要

This paper presents an improved technique for the calibration of the relaxation oscillators with respect to the delay of the comparators. The drawbacks of the conventional topology for the relaxation oscillators are analyzed. Based on the analysis, the circuit modification which resolves the effects of the comparator delay in the trimming procedure is proposed. The simulations in ams 0.18μ CMOS technology exhibit more than 5x the improvement in the precision compared to the conventional topology, evaluated in the temperature range from -40 to 125 °C.