Integration of CMOS Photodiode and Capacitive Charge Pump Circuits for On Chip Photovoltaic Energy Harvesting

This paper presents a CMOS photodiode model that can be fabricated using 65-nm triple-well CMOS technology and its integration with different charge pump circuits for on-chip photovoltaic energy harvesting performed with 650-nm laser light illumination. A selected photodiode configuration available in triple-well technology is simulated to obtain its current-voltage characteristics and develop an equivalent circuit model. Different charge pump circuits are connected to the circuit model of the CMOS photodiode and their combined performances are compared with each other. This photovoltaic energy harvesting system including a CMOS photodiode and a charge pump circuit is designed to supply the integrated circuit blocks in a Magnetic Resonance Imaging (MRI) receiver which means no external power supply and cables are needed. The integrated design reveals an output voltage of 1.09V and an output current of 4.37mA for the charge pump circuit. The simulated output voltage ripple is 7.50mV and efficiency is 70.43%.