CN2757279Y

CN2757279Y - Once programmable operation device for liquid crystal display module driving chip

Info

Publication number: CN2757279Y
Application number: CN 200420105438
Authority: CN
Inventors: 黄昕熙
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2004-11-30
Filing date: 2004-11-30
Publication date: 2006-02-08
Anticipated expiration: 2014-11-30

Abstract

The utility model relates to a once programmable operation device for driving chips of liquid crystal displays, which comprises a casing, keys, a key circuit and a control circuit solidified with OTP software, wherein the keys are arranged on the casing, the key circuit is corresponding to the keys and is triggered by the keys, and the control circuit is connected with the output end of the key circuit. The keys comprise a contrast increase key, a contrast decrease key and a burning key. The control circuit comprises an SCM, and the output end of the key circuit is connected with a corresponding pin of the SCM. The control circuit also comprises a step up circuit connected with the pin of the SCM. The key also comprises a restoring key which is corresponding to a restoring key circuit, and the restoring key circuit is connected with the control circuit. Because the utility model can adjust the output voltage of driving chips of a liquid crystal display module through key operation, operation is simplified, and the production efficiency is increased.

Description

The chip for driving of LCD MODULE is carried out the device of One Time Programmable operation

[technical field]

The utility model relates to the LCD MODULE field, especially carries out the device of One Time Programmable operation about a kind of chip for driving to LCD MODULE.

[background technology]

Since lcd technology is succeeded in developing, the little power consumption of low-voltage, flat structure show because it has, the display message amount is big, be easy to colorize, long-life, unique advantage such as radiationless, pollution-free, now have been widely used in fields such as mobile phone, portable computer, video camera.

As the display unit of hand system, liquid crystal display device is the interface of man-machine interaction, so the display effect of liquid crystal display device is quite important for total system.Because LCD MODULE is the capacitive device of low voltage drive, so the variation of driving voltage is significant to the influence of liquid crystal display effect.

The LCD MODULE (LCM) that is widely used in handset displays at present is made up of LCD (LCD) and liquid crystal controlling and driving chip (LCD Driver IC).In general, as the product of producing in batches, the operating voltage of same batch LCD or the output voltage of IC all have deviation in various degree.Because LCD is the passive-type device, every electric parameter can't change after producing, so want the display effect deviation of LCD MODULE is adjusted, the output voltage of adjusting chip for driving is unique feasible reliable method.General drive IC inside all can have contrast that instruction regulation voltage output effectively is set, and corresponding different lcd drive voltage is provided with different contrast level parameter just can make LCD MODULE reach best display effect.But owing to produce the existence of the deviation of product in batches, meaning for each LCD MODULE all to have different parameter settings, and this client to the overwhelming majority is unacceptable.At such problem, many Color Liquid Crystal Display chip for driving all provide the OTP function, and (full name is One Time Programable, Chinese is: One Time Programmable), allow LCM production firm that the benchmark of IC output voltage is regulated, become the conforming method of a kind of effective guarantee bulk article.

But, the way of prior art is to realize by the operation on the pure software, all need to re-enter the contrast value of setting for each LCD by the mode of revising parameter in the software, how because be not that each common laborer knows debugging software, so this brings difficulty to production, and complicated operation, reduced production efficiency.

[utility model content]

The purpose of this utility model is to provide a kind of simple to operate and device that the chip for driving to LCD MODULE that can enhance productivity is carried out the One Time Programmable operation.

The purpose of this utility model is achieved in that a kind of chip for driving to LCD MODULE carries out the device of One Time Programmable operation, comprise key circuit and be solidified with the control circuit of OTP software, control circuit is connected with the output terminal of key circuit, and control circuit receives the control signal of key circuit output and handles.

Described key circuit comprises contrast adjustment button and burning button.

Described contrast adjustment button comprises that contrast increases button and contrast reduces button.

Described control circuit comprises single-chip microcomputer, and the output terminal of key circuit is connected with the corresponding pin of single-chip microcomputer.

Described key circuit also comprises the booster circuit that is connected with the pin of single-chip microcomputer.

Described key circuit also comprises the reset key circuit that is connected with the pin of single-chip microcomputer.

Also comprise housing, the button of key circuit is arranged on this housing.

Compared with prior art, the utlity model has following advantage:,, improved production efficiency so simplified operation owing to, can realize that the output voltage of the chip for driving of LCD MODULE is regulated by button operation.

[description of drawings]

Fig. 1 is one-piece construction figure of the present utility model.

Fig. 2 is the circuit theory diagrams of control circuit of the present utility model.

Fig. 3 is the circuit theory diagrams of booster circuit of the present utility model.

Fig. 4 to Fig. 7 is respectively the key circuit figure of BURN of the present utility model, RESET, C_R and C_A button.

[embodiment]

See also Fig. 1, the utility model carries out the device of One Time Programmable operation to the chip for driving of LCD MODULE, it is regulated the contrast of chip for driving by the OTP function that chip for driving carries, and this chip for driving is arrived in preferable OTP parameter programming.This device comprises housing 1 and is located at circuit part in this housing 1 that circuit part comprises key circuit and control circuit.Key circuit has three, be respectively contrast and increase key circuit, contrast reduction key circuit and burning key circuit, these three key circuits comprise that respectively the button contrast increases button 2 (i.e. C_A button in the diagram), contrast reduces button 3 (i.e. C_R button in the diagram) and burning button 4 (i.e. BURN button in the diagram), and this

button

2,3,4 is installed on the housing 1 by prior art.Control circuit is connected with the output terminal of key circuit, and this control circuit is solidified with OTP software, thereby by pushing three buttons, makes control circuit carry out respectively that contrast increases, contrast reduces and the operation of burning.Certainly, also the reset key circuit can be set on the housing, in order to system reset, this reset key circuit comprises reset key (i.e. RESET button in the diagram).

This control circuit comprises the interface circuit of single-chip microcomputer U1, electrifying self-resetting circuit, wire jumper circuit, booster circuit, crystal oscillating circuit and LCD MODULE.Single-chip microcomputer U1 is 8052 chips, has number of pins, and wherein P30-P35 exports normal control timing as control interface, operation such as control strip selects, resets, reading and writing; P21-P23 is a keystroke interface, connects three buttons of C_A, C_R and BURN respectively.Press the C_A button and realize that the contrast of LCD MODULE adds 1, press the C_R key and realize that the contrast of LCD MODULE subtracts 1, presses the register that the BURN key writes the contrast value of the best the chip for driving of LCD MODULE; Whether the work of P24 control booster circuit, during for low level, activates booster circuit, and the burning voltage of output 15V is realized the register of chip for driving is carried out programming; The P10-P17 pin realizes that as standard I/O data transmit; The RESET pin is connected with the reset key circuit; XTAL2 and XTAL1 pin are connected with crystal oscillating circuit.

The electrifying self-resetting circuit is a prior art, it is connected with the RESET pin of single-chip microcomputer U1, the principle of work of this electrifying self-resetting circuit is as follows: the moment that VDD powers on, capacitor C 4 conductings, the voltage that then is added on the RESET pin becomes VDD by 0V, be that the VESET pin detects a high impulse, realize resetting.The wire jumper circuit is connected with the EA/VPP pin of single-chip microcomputer U1, in order to convenient the EA/VPP pin of single-chip microcomputer is received high level or low level.The interface circuit of LCD MODULE is in order to electrically connect with LCD MODULE.

Booster circuit is connected with the P24 pin of single-chip microcomputer U1, in order to the OTP burning voltage of control output 15V.The voltage of 3V can produce 15V burning voltage after passing through boosting of this circuit, and realization is carried out programming to the register of the chip for driving of LCM.P24 and 15V_EN are the control signal input pin, and this enforcement Fang Shizhong uses P24 foot control system, and 15V_EN keeps pin.When P24 is high level, triode Q1 conducting, the SHDN pin is a low level; When P24 was low level, triode Q1 ended, and the SHDN pin is a high level, and in fact this booster circuit realizes the function of reverser.Booster circuit has the chip of boosting, and at this enforcement Fang Shizhong, the model of the chip U2 that boosts is LT1565, and it has number of pins, and wherein: SW is a switch pin, and this is the collector of inner NPN power switch; GND is a grounding pin; FB is a feedback pin, sets output voltage by the value of selecting resistance R 1 and R2: R1=R2 (Vout/ (1.23～1)); SHDN is for shutting down pin, this pin received 0.9V or higher current potential can activate this device, this pin received can be closed this device below the 0.25V; Vin is the input power pins.Certainly, can not select booster circuit yet and directly reach the purpose of boosting by the external dc stabilized voltage supply.

Device of the present utility model carries out burning to the chip for driving (as the SSD1781 chip of Solomon company) of LCM and comprises that two step: OTP are provided with step and two steps of OTP burning, wherein, OTP is provided with step mainly in order to find the suitable side-play amount of contrast, and OTP burning step is in order to carry out the programming of OTP parameter to chip for driving.The course of work of this device is as follows: 1) OTP software initialization, LCM is provided with normal operating conditions, and the contrast reference value is set, and shows a width of cloth picture, can observe display effect by this picture; 2) software responses " C_A " or " C_R " button, and call corresponding program (" contrast increase " or " contrast reduction " program), at this moment can see that display effect is conditioned, and current contrast value of setting and the deviation " Δ " of the value of pre-seting be charged to the register of this device; 3) judge " Δ " value,, otherwise show warning " exceeding range of adjustment " and return default contrast value show state, represent that this module can't adjust to normal display state by OTP if in the OTP range of adjustment (+7 ,-8), then carry out next step; 4) response " BURN " button enters OTP operation (comprise reset, open crystal oscillator, write the OTP instruction, drive LT1615 output external power source or directly add operations such as stabilized voltage supply 15V, time-delay 2～5S, the outside power supply in pass according to " Δ " value in the register); 5) reinitialize, show original picture, observe and verify the effect of OTP operation.

Claims

1. the chip for driving to LCD MODULE is carried out the device that One Time Programmable is operated, it is characterized in that: it comprises key circuit and is solidified with the control circuit of OTP software, control circuit is connected with the output terminal of key circuit, and control circuit receives the control signal of key circuit output and handles.

2. the chip for driving to LCD MODULE as claimed in claim 1 is carried out the device of One Time Programmable operation, and it is characterized in that: described key circuit comprises contrast adjustment button and burning button.

3. the chip for driving to LCD MODULE as claimed in claim 2 is carried out the device of One Time Programmable operation, it is characterized in that: described contrast adjustment button comprises that contrast increases button and contrast reduces button.

4. the chip for driving to LCD MODULE as claimed in claim 1 is carried out the device of One Time Programmable operation, and it is characterized in that: described control circuit comprises single-chip microcomputer, and the output terminal of key circuit is connected with the corresponding pin of single-chip microcomputer.

5. the chip for driving to LCD MODULE as claimed in claim 4 is carried out the device of One Time Programmable operation, and it is characterized in that: described key circuit also comprises the booster circuit that is connected with the pin of single-chip microcomputer.

6. the chip for driving to LCD MODULE as claimed in claim 4 is carried out the device of One Time Programmable operation, and it is characterized in that: described key circuit also comprises the reset key circuit that is connected with the pin of single-chip microcomputer.

7. carry out the device of One Time Programmable operation as any described chip for driving to LCD MODULE among the claim 1-6, it is characterized in that: also comprise housing, the button of key circuit is arranged on this housing.