Power supply device for electromagnetic induction module of electromagnetic liquid crystal touch screen

Abstract

The invention discloses a power supply device for an electromagnetic induction module of an electromagnetic liquid crystal touch screen, belonging to periphery equipment of computers. Without changing the function of the touch screen, the current requirement of the electromagnetic induction module for the computer is lowered to below 1mA. The working current of the electromagnetic induction module is not directly supplied by a USB interface of the computer again but supplied by a power module of the touch screen. A voltage conversion circuit and a switch circuit are connected between the power module and the electromagnetic induction module and are respectively connected with the USB interface of the computer. A power end of the USB is connected with a control port and a power input end of the switch circuit. An output port of the voltage conversion circuit is connected with an input port and a power input end of the switch circuit. By adopting the device, after the working current of the electromagnetic induction module is supplied by the power module of the touch screen, the output current of the USB interface of the computer is greatly lowered, thereby avoiding the aging of a USB controller of the computer.

Description

technical field [0001] The invention belongs to the field of computer peripheral equipment and relates to a power supply device for an electromagnetic induction module of an electromagnetic liquid crystal touch screen. Background technique [0002] At present, electromagnetic touch technology is favored by the market due to its high positioning accuracy, the ability to obtain pen tilt angle and pressure information, and not affect the quality of screen display when used in the display field. It is widely used in Tablet PC (handwriting computer), drawing board , tablet, mobile phone, e-book and other equipment. [0003] The electromagnetic liquid crystal touch screen is composed of an electromagnetic induction module and a liquid crystal component. The electromagnetic induction module consists of an electromagnetic induction screen and an electromagnetic pen, and is used to control handwriting input. The specific working principle is: the electromagnetic induction screen em...

AI Technical Summary

Problems solved by technology

[0006] When the electromagnetic LCD touch screen is connected to the computer, the following problems are likely to occur: the electromagnetic induction module of the electromagnetic LCD touch screen is powered by the computer through the USB port. After a long time of work, it is easy to cause the USB controller of the computer to age and affect the service life of the computer. ; Some computers have a low power supply. If the electromagnetic induction module of the electromagnetic LCD touch screen is connected to the computer when the computer is started, the computer cannot be started normally.

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