1.81 kHz Relaxation Oscillator With Forward Bias Comparator and Leakage Current Compensation Based Techniques

We propose a 1.81 kHz on-chip relaxation oscillator implemented in 0.18 µm CMOS technology without trimming. The first order temperature coefficient (TC) is compensated by leakage current. The stability is further enhanced by a forward bias comparator that suppresses offset variation. The oscillator consumes 11.69 nW from a 0.8 V power supply and the TC is 49.3 ppm/°C for a temperature range from -20°C to 80°C. The simulated line sensitivity is 1.8% with voltage supply ranging from 0.5 V to 2.0 V.