Controller of liquid crystal display

Abstract

The invention provides a controller of a liquid crystal display, which adopts a charge pump design of an on-chip capacitor, greatly saves peripheral devices and packaging area, and comprises a low-power-consumption oscillator used for generating a clock signal; the frequency divider is used for carrying out frequency division on a clock source and outputting a clock signal after frequency division; the charge pump inputs power supply voltage and clock signals and outputs boost voltage, and the voltage selector outputs target voltage; the bias voltage generator inputs a target voltage and is used for outputting a group of bias voltages by utilizing the target voltage; the comparator is used for outputting a comparison result; the filter outputs a control signal according to the comparison result, and the control signal is used for controlling frequency selection of the frequency divider; the buffer is used for buffering the group of bias voltages to obtain a group of buffer voltages; the selector matrix is used for selecting a group of buffer voltages output from the buffer through digital control to select a target buffer voltage, and outputting the target buffer voltage to the display screen.

Description

technical field [0001] The invention relates to the field of display driving, in particular to a controller of a liquid crystal display. Background technique [0002] At present, as a display of a portable electronic device, a segment code type liquid crystal panel is generally used, and a plurality of display pixels are arranged in a matrix in the segment code type liquid crystal panel. In this portable electronic device, a controller for controlling the segment type liquid crystal panel is also installed. The controller is used to drive the driver circuit of the segment code LCD panel. With the continuous improvement of the integration of integrated circuits, the charge pump circuit is increasingly integrated in the controller of the liquid crystal display. However, due to the high requirements of the charge pump circuit on the power supply, in order to reduce the ripple of the charge pump circuit on the power supply Interference, generally need to increase the large off...

AI Technical Summary

Problems solved by technology

With the continuous improvement of integrated circuit integration, the charge pump circuit is more and more integrated in the controller of the liquid crystal display, but because the charge pump circuit has high requirements on the power supply, in order to reduce the ripple of the charge pump circuit Interference generally requires adding large off-chip capacitors at its power port, which not only increases the cost of the power supply system, but also reduces the reliability of the entire system

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