Active matrix display device

Abstract

To reduce power consumption of an active matrix type display device.A holding circuit 110 for holding a video signal every pixel is provided, and a normal operation mode and a memory operation mode are switched to each other for displaying. In the memory operation mode, an output of a booster circuit 200 arranged in a panel is used as a reference voltage of the holding circuit 110, and also a selection circuit is changed over. The power consumption is reduced by halting the operation of a booster circuit of an external circuit and a driver circuit in the panel. Voltage higher than the maximum voltage value applicable to the pixel electrode in the memory operation mode is applied to the gate of a circuit selection transistor or / and a data output transistor. In the normal operation mode, the booster circuit 200 is halted.

Description

[0001] This application is a divisional application of: [0002] Invention name: active matrix display device [0003] Application date: April 12, 2002 [0004] Application number: 02105526.2 technical field [0005] The present invention relates to an active matrix display device, and more particularly to an active matrix display device provided with a plurality of holding circuits corresponding to pixels. Background technique [0006] In recent years, as a market demand, display devices are required to be portable, such as portable televisions, mobile phones, and the like. In response to such demands, research and development for miniaturization, weight reduction, and power saving of display devices has been actively conducted. Japanese Unexamined Patent Publication No. 2000-282168 discloses a liquid crystal display device in which a static random access memory (SRAM) is provided in each display pixel to display a still image. [0007] Figure 5 A circuit configuration...

AI Technical Summary

Problems solved by technology

[0038] However, in the existing active matrix display device with a holding circuit, the voltage for making the holding circuit operate is supplied from the external circuit board 90 in the storage operation mode, and the number of power supplies and the number of control signals in the storage operation mode Many, there is a disadvantage that the number of terminals on the panel 100 is large

[0039] In addition, in the storage operation mode, the boosted voltage VVDD is also used as the power supply voltage, so it is necessary to continue the operation of the boost circuit on the external circuit board 90, and the power consumption is large in the storage operation mode.

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