On Two-Phase Switched-Capacitor Multipliers With Minimum Circuit Area

This paper compares the performance among two-phase switched-capacitor multipliers to identify the optimum topology with the smallest circuit area. The optimum number of stages is calculated for every multiplier to minimize the circuit area under the condition that a certain current is outputted with a given output voltage. Then, the circuit areas of the serial-parallel, linear (LIN), Fibonacci, and 2
^N
multipliers are compared. Results show that the LIN cell is the best for integration because of the smallest total capacitor area and the highest current efficiency under the assumption that the parasitic capacitance is not smaller than 10% of the multiplier capacitance, and the Fibonacci cell is the best for discrete application because of the minimum number of capacitor components with moderate current efficiency under the assumption that the parasitic capacitance is not larger than 1% of the multiplier capacitance.