A fully-integrated ambient RF energy harvesting system with 423-mu W output power

• Main Authors: Churchill, Kishore Kumar Pakkirisami, Ramiah, Harikrishnan, Chong, Gabriel, Chen, Yong, Mak, Pui-In, Martins, Rui P.
• Format: Article
• Published: MDPI 2022
• Subjects: QD Chemistry; TA Engineering (General). Civil engineering (General)
• Online Access: http://eprints.um.edu.my/41948/

This paper proposes a 2.4-GHz fully-integrated single-frequency multi-channel RF energy harvesting (RFEH) system with increased harvested power density. The RFEH can produce an output power of similar to 423-mu W in harvesting ambient RF energy. The front-end consists of an on-chip impedance matching network with a stacked rectifier concurrently matched to a 50 omega input source. The circuit mitigates the ``dead-zone'' by enhancing the pumping efficiency, achieved through the increase of V-gs drivability of the proposed internal gate boosting 6-stage low-input voltage charge pump and the 5-stage shared-auxiliary-biasing ring-voltage-controlled-oscillator (VCO) integrated to improve the start-up. The RFEH system, simulated in 180-nm complementary metal-oxide-semiconductor (CMOS), occupies an active area of 1.02 mm(2). Post-layout simulations show a peak power conversion efficiency(PCE) of 21.15%, driving a 3.3-k omega load at an input power of 0 dBm and sensitivity of -14.1 dBm corresponding to an output voltage, V-out,V-RFEH of 1.25 V.