Liquid crystal display and gate modulation method thereof
A gate modulation circuit is provided. A comparator compares a triangular wave voltage of a capacitor with a second reference voltage. If the triangular wave voltage of the capacitor exceeds the second reference voltage, a conduction path is turned off. A comparator controls desired discharge to a capacitor through a discharge resistor. Based on the discharge, power voltage (high level power voltage of the scanning driver) provided to the scanning driver is modulated, and outputted from the gate modulation circuit to the scanning driver as high level power voltage of the scanning driver.
1. A gate signal modulation circuit, comprising:
a power voltage for providing operating power to the circuit;
a basis voltage for providing a basis voltage to the circuit;
a constant current generator for providing a constant current;
a first capacitor coupled to the constant current generator for providing a charging voltage;
a triangle wave generator comprising a control node receiving a timing signal for controlling a rising edge and a falling edge of a gate signal to generate a triangle wave voltage for the first capacitor according to the timing signal;
a modulation controller for outputting a modulated control signal according to a comparison result of the triangle wave voltage and the basis voltage; and
a modulated voltage generator comprising a second capacitor coupled to the power voltage, wherein the modulated voltage generator determines whether the second capacitor is charged by the power or discharged according to the modulated control signal and generates a modulated voltage.