Patent ID: 7532033

Claim:
A level shifting apparatus for shifting a level of a data signal, comprising: a first charge pump, supplying a first pumped voltage based on the data signal, wherein the first charge pump comprises: a capacitor having a first node and a second node, wherein the second node is for receiving a first pumping signal; a first switch selectively connecting a low voltage source and the first node of the capacitor; a second switch selectively connecting the first node of the capacitor and a pump output node of the first charge pump for outputting the first pumped voltage; and a third switch selectively connecting the pump output node and a reference voltage source; a diode connecting to the low voltage source; and a fourth switch selectively connecting the low voltage source and the pump output node and controlled by the first pumping signal; and a level shifter, having an input node to receive the first pumped voltage for generating a level-shifted data signal based on the first pumped voltage.