New Discrete Fibonacci Charge Pump Design, Evaluation and Measurement

Abstract

This paper focuses on the practical aspects of the realisation of Dickson and Fibonacci charge pumps. Standard Dickson charge pump circuit solution and new Fibonacci charge pump implementation are compared. Both charge pumps were designed and then evaluated by LTspice XVII simulations and realised in a discrete form on printed circuit board (PCB). Finally, the key parameters as the output voltage, efficiency, rise time, variable power supply and clock frequency effects were measured.

Rationalisation of the Fibonacci Charge Pump

“…The result of the design procedure [6] leads to the identification of values of capacitance of the transfer and load capacitors and types of active elements, see Table I. The proposed FCP circuit solution according to Fig.…”

“…Furthermore, the FCP circuit has a higher sensitivity for on-chip parasitic than Dickson charge pump circuit solution. Thus, the FCP concept is especially attractive to the pump realized by discrete components [4], [5], [6].…”

“…Efficiency vs. output current for various values of capacitance of capacitors calculated by simulation[6].…”

Streamlined Fibonacci Charge Pump

“…The original FCP was designed in [6] for power supply voltage VIN = 3 V and the minimal steady-state output voltage VOUT = 30 V at the output current IOUT = 1 mA. The auxiliary parameters were maximal ripple voltage of the output VR = 15 mV and the maximal rise time of the output tR = 65 ms.…”

“…The main disadvantage of FCP is an increased sensitivity to parasitic capacitors than DCP. Thus, the FCP concept is recommended for lower frequencies than DCP [4], [5], [6] only.…”