A 0.4 V Low Frequency Voltage-Controlled Ring Oscillator Using DTMOS Technique

In this paper, an ultra-low power ultra-low voltage five-stage low frequency voltage–controlled single-ended ring oscillator using dynamic threshold voltage MOSFET (DTMOS) is presented. The proposed oscillator is designed and simulated using TSMC 0.18μm RF CMOS technology with 0.4 V power supply. In this design all transistors working at the sub-threshold (weak inversion) region. The output frequency ranges from 26.6-210.5 kHz with control voltages of 0 V to 0.4 V. Its power consumption and phase noise at a 100 kHz offset at the minimum(maximum) oscillation frequency is respectively 6.42nW (8.62 nW) and -120.5 dBc/Hz (-113.15 dBc/Hz).