A 0.8 V Low-Power Wide-Tuning-Range CMOS VCO for 802.11ac and IoT C-Band Applications

This paper presents a 0.8 V low-power CMOS voltage-controlled oscillator (VCO) with a wide tuning range, fabricated using a TSMC 0.18 μm process. The proposed design incorporates body-biasing techniques and an optimized varactor structure to achieve a tuning range of 1124 MHz (5.829–4.705 GHz) and low phase noise of −117.6 dBc/Hz at a 1 MHz offset. Operating at an ultra-low supply voltage of 0.8 V, the VCO consumes only 3.4 mW, demonstrating excellent power efficiency. A buffer circuit is also employed to enhance output symmetry and suppress flicker noise without introducing additional control complexity. With a figure-of-merit (FOM) of −188.6 dBc/Hz and a wide tuning range of 22.2%, the proposed VCO is well-suited for modern low-power communication systems, including 802.11ac, 5G transceivers, satellite links, and compact IoT devices.