Patent ID: 6515642
Filing Date: 2003-02-04
Classification: G09G

Abstract:
A driving circuit for a liquid crystal display, comprising a plurality of dynamic controllers, each dynamic controller comprising:an operating amplifier including a CMOS differential amplifier, a first PMOS transistor (5) and a first NMOS transistor (3), wherein a load of the CMOS differential amplifier is a second PMOS transistor, a gate terminal of the second PMOS transistor and a gate terminal of the first PMOS transistor are connected with each other with the supply of a constant source voltage thereto, drain terminals of the first and second PMOS transistors are both connected to a drain supply voltage terminal of the dynamic controller, a source terminal of the first PMOS transistor and a drain terminal of the first NMOS transistor are both connected to an output voltage (Vo) terminal of the dynamic controller, and source terminals of the first NMOS transistor and the CMOS differential amplifier are both connected to a source power voltage terminal of the dynamic controller; and a Schmitt comparator of which a positive comparing terminal and a negative comparing terminal are connected to the output voltage (Vo) terminal and an input voltage (Vi) terminal of the dynamic controller, respectively, an output voltage terminal of the comparator is connected to a gate terminal of a third PMOS transistor (MP1) acting as a switch, the gate terminal of the third PMOS transistor is connected to the drain supply voltage terminal of the dynamic controller, a source terminal of the third PMOS transistor is connected to the output voltage (Vo) terminal via a current control resistor, two strobe terminals of the Schmitt comparator are connected to the drain supply voltage terminal of the dynamic controller and a drain terminal of a second NMOS transistor, respectively, and a gate terminal and a source terminal of the second NMOS transistor are connected to a power-on signal terminal and the output voltage (Vo) terminal of the dynamic controller, respectively.