Patent ID: 9083231
Filing Date: 2015-07-14
Classification: H02M

Abstract:
1. A method of operating a charge pump circuit, the charge pump including one or more stages each having one or more legs, including a first leg connected between an output node for the corresponding stage and an input node for the corresponding stage receiving an input voltage for the stage, and the first leg has a first capacitor with a first plate connected to an internal node thereof and a first output transistor connected between the internal node and the output node of the corresponding stage, the method comprising: applying a first clock signal to a second plate of first capacitor, the first clock signals value alternating between a high value and a low value; applying a second clock signal to the gate of the first output transistor, wherein the second clock signal is of the same phase as the first clock signal, and wherein the second clock signal has a low value that is higher than the input voltage for the stage, being offset above the input voltage by an amount not more than the than the threshold voltage of the first output transistor; and generating the second clock signal from the first clock signal using an auxiliary charge pump section including one or more stages each having one or more legs, the second clock signal being generated by a first of the legs thereof, wherein the first leg of the auxiliary charge pump section is connected to ground through a diode, whereby the voltage offset is implemented.