Liquid crystal screen contrast adjustment circuit for monitoring equipment

Abstract

The invention discloses a liquid crystal screen contrast adjustment circuit for monitoring equipment, relates to the technical field of liquid crystal display, and aims to solve the technical problem of inconvenient adjustment of the contrast of a liquid crystal screen of the prior monitoring equipment. The circuit comprises a display driving module, and is characterized in that: the circuit alsocomprises a key scanning circuit for inputting a contrast adjustment value, a key driving module of which the input end is connected with the key scanning circuit, a data latching module used for generating a reference adjustable circuit, and a triode, wherein an enable end of the data latching module is always effective, a control end is connected with a system control signal, an input end is connected with a data output end of the key driving module, an output end is connected with an exclusion, and a public end of the exclusion is serially connected with a resistor and then earthed; and a base electrode of the triode is connected with the public end of the exclusion, an emitting electrode is serially connected with a pull-up resistor, a collector electrode is connected with a display screen contrast adjustment end of the display driving module, and the resistor is connected with a display screen voltage output end of the display driving module. The circuit provided by the inventioncannot influence normal operation of the equipment in the adjusting process.

Description

technical field [0001] The invention relates to liquid crystal display technology, in particular to a technology for adjusting the contrast ratio of a liquid crystal screen of a monitoring device. Background technique [0002] In the power system, the human-machine interface system of various monitoring equipment provides users with a simple and friendly query service function. Users only need to operate the keyboard to enter the menu to query various semaphores or control their operations, and through the LCD screen. The operation process and operation results are fed back to the user. In the production of traditional monitoring equipment, manual adjustment of the potentiometer is used to adjust the contrast of the LCD screen to achieve the best display state, but it is difficult to improve its adjustment efficiency and quality in the case of mass production of equipment; and various use occasions The environment is different, and it is difficult to ensure that the contras...

AI Technical Summary

Problems solved by technology

In the production of traditional monitoring equipment, manual adjustment of the potentiometer is used to adjust the contrast of the LCD screen to achieve the best display state, but it is difficult to improve its adjustment efficiency and quality in the case of mass production of equipment; and various use occasions The environment is different, and it is difficult to ensure that the contrast of the LCD screen will not drift during the operation of the equipment. At this time, if you want to adjust it, you need to open the case, and you need a professional to adjust it. The adjustment is extremely inconvenient, and a little carelessness will seriously affect the The normal operation of the equipment brings serious hidden dangers to the safe production of enterprises

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