Patent ID: 7071758

Claim:
A voltage level shifter, comprising: an AND gate for processing a first control signal and an input signal to produce a synchronizing signal, wherein the first control signal is a periodic signal; a transistor device having a first transistor and a second transistor, wherein a drain of the first transistor and a drain of the second transistor are electrically connected at a first contact point, a source of the first transistor then is electrically connected to a ground and a source of the second transistor is electrically connected to a voltage source, a gate of the first transistor is electrically connected to the synchronizing signal and a gate of the second transistor is electrically connected to a second control signal having the same phase as the first control signal; a switch, controlled by the second control signal, wherein one terminal of the switch is electrically connected to the first contact point and the other terminal of the switch is electrically connected to a second contact point; a buffer for producing an output signal, wherein an input terminal of the buffer is connected to the second contact point; and a capacitor, wherein one terminal of the capacitor is electrically connected to the second contact point for storing a signal level of the second contact point, and the other terminal of the capacitor is electrically connected to the ground.