Charge pump circuit and methods of operations thereof

摘要

A charge pump circuit, and associated method and apparatuses, for providing a split-rail voltage supply, the circuit having a network of switches that is operable in a number of different states and a controller for operating the switches in a sequence of said states so as to generate positive and negative output voltages together spanning a voltage approximately equal to the input voltage and centered on the voltage at the common terminal.

主权项

1. A charge pump circuit comprising:
an input terminal for receiving an input voltage; a common terminal; first and second output terminals for connection to respective first and second reservoir capacitors; first and second flying capacitor terminals for connection to a first flying capacitor; third and fourth flying capacitor terminals for connection to a second flying capacitor; a switch network connected to said input terminal, said common terminal, said first and second output terminals and said first, second, third and fourth flying capacitor terminals; said switch network being operable in at least a first mode of operation in a sequence of states comprising at least a first state and a second state so as to generate first positive and negative output voltages respectively at said first and second output terminals; wherein in said first state said first and second flying capacitors are connected in series between the input terminal and the common terminal and disconnected from the first and second output terminals; and wherein in said second state said first flying capacitor is connected in parallel with one of the first and second reservoir capacitors while, at the same time, said second flying capacitor is connected in parallel with the other one of said first and second reservoir capacitors.