US Patent 7119781 Active matrix display precharging circuit and method thereof

A precharge system for active matrix display devices having data and scan lines, pixels, and first and second voltage sources. The precharge system comprises a precharge circuit having first transistors, with gate electrode and drain electrode connected to function as a diode, of which a first terminal is coupled to the first voltage source, a second transistor of which a first terminal is coupled to the second terminals of the first transistors, a second terminal is coupled to the data lines, and a control terminal receives a positive precharge signal, third transistors, connected to function as a diode, of which a first terminal is coupled to the second voltage source, and a fourth transistor of which a first terminal is coupled to the second terminals of the third transistors, a second terminal is coupled to the corresponding data lines, and a control terminal receives a negative precharge signal.