Patent ID: 8044707
Filing Date: 2011-10-25
Classification: H02M

Abstract:
1. A method for generating from a single supply voltage Vdd energy efficient supply voltages, comprising values of Vdd/6 and Vdd/5 being symmetrical around ground voltage, comprising the following steps: (1) providing an input voltage Vdd and a charge pump circuit, having a positive and a negative output node, comprising a digital controller, a set of switches, at most two flying capacitors, and two reservoir capacitors; (2) setting output voltage modes desired on the digital controller, comprising values of Vdd/6 and Vdd/5 being symmetrical around ground voltage; (3) setting switches in order to put voltages on the at most two flying capacitors and on at least one output port according to one or more equations describing a first phase of an actual output voltage mode of the charge pump; (4) setting switches in order to put voltages on the at most two flying capacitors and on at least one output port according to one or more equations describing a second phase of an actual output voltage mode of the charge pump; (5) setting switches in order to put voltages on the at most flying capacitors and on one or more output port according to one or more equations describing a third phase of an actual output voltage mode of the charge pump; (6) setting switches in order to put voltages on the at most two flying capacitors and on one or more output port according to one or more equations describing a fourth phase of an actual output voltage mode of the charge pump; (7) go to step (8) if charge pump is on, else go to step (10); (8) go to step (9) if output voltage mode is to be changed, else go to step (3); (9) change output voltage mode and go to step (3); and (10) end.