CN203165418U

CN203165418U - Circuit capable for improving stability of LED display screen under high refresh frequency

Info

Publication number: CN203165418U
Application number: CN2012207496127U
Authority: CN
Inventors: 陈阿军; 姚进根; 杨佰成; 张真桂; 王宝良; 张志鹏
Original assignee: FUSHUN OPTOELECTRONICS TECHNOLOGY Co Ltd
Current assignee: FUSHUN OPTOELECTRONICS TECHNOLOGY Co Ltd
Priority date: 2012-12-31
Filing date: 2012-12-31
Publication date: 2013-08-28
Anticipated expiration: 2022-12-31

Abstract

The utility model relates to a circuit capable for improving the stability of an LED display screen under high refresh frequency. The circuit includes more than one field-effect transistor, a decoder, driving chips and LED lamp tubes in array distribution; a power source output end of an LED control system is respectively connected with source poles of the field-effect transistors and a power source input end of the driving chip; the LED lamp tubes in array distribution are divided into n rows and m columns, where in n and m are integers greater than zero; after being connected in parallel with each other, positive poles of LED lamp tubes in each row are connected to a drain pole of one field effect transistor; after being connected in parallel with each other, negative poles of LED lamp tubes in each column are connected to a driving port of one driving chip; the driving port is connected with negative poles of more than one column of LED lamp tubes; the driving chips are connected in series with each other; a first driving chip is connected with the LED control system; and gate poles of the field-effect transistors are respectively connected with the decoder. With the circuit of the utility model adopted, dark lightness, trailing smear, interference and jitter of the LED display screen under high refresh frequency can be eliminated, and therefore, the LED display screen is free from distortion and jitter.

Description

A kind of circuit that improves high refreshing frequency LED display stability

Technical field

The utility model relates to the LED display technical field, particularly a kind of circuit that improves high refreshing frequency LED display stability.

Background technology

Along with the demand of the marketing policy, the development of LED full color display is more and more faster, and the just past super-high density of indoor full-color LED display screen, height refresh, high gray develops; Indoor full-color LED display screen generally adopts dynamic scan mode, even under common refreshing frequency, usually can occur secretly bright, smear, interference phenomenon, still more in high refreshing frequency, general LED cell board is in order to design conveniently in the prior art, the LED fluorescent tube adopts with driving chip connected mode the folding mode, when adopting four/one scan mode such as LED display, each drives the eighty percent discount mode of four LED fluorescent tubes of driving port connection of chip, drive chip and comprise that 16 of OUT0-OUT15 drive port, driving OUT0-OUT7 in the chip, to drive port be four lines eight row fluorescent tubes before driving, and driving OUT8-OUT15 in the chip, to drive port be to drive the back to follow fluorescent tube behind the four lines eight row fluorescent tubes; When the LED control system sent demonstration information, the first eight row of fifth line were sent out after sending the first eight row of first row again by elder generation, then behind the first eight row of second row, sent out the 6th the first eight row of row again, so distributed eight row, eight columns certificates; This LED fluorescent tube distributed architecture has increased the driving chip and has sent data line feed number of times, and LED fluorescent tube and arrangement architecture are unreasonable simultaneously, and the frequency of the flicker that occurs during the scanning line feed is higher, and visual effect was poorer when this will cause the LED display displaying video; Therefore, it is necessary proposing a kind of circuit that solves and improve high refreshing frequency LED display stability.

Summary of the invention

The purpose of this utility model is to provide a kind of LED display that solves secretly a kind of circuit that improves high refreshing frequency LED display stability of the phenomenon of bright, smear, interference and shake to occur.

The utility model adopts following structure, the circuit of the high refreshing frequency LED display of described raising stability is electrically connected with the LED control system, it is electrically connected with the LED control system, and it comprises the LED fluorescent tube of an above field effect transistor, code translator, plural driving chip and array arrangement; The power output end of described LED control system connects the source electrode of more than one field effect transistor and the power input of plural driving chip respectively; The LED fluorescent tube of described array arrangement is divided into the capable and m row of n, and wherein n and m are the integer greater than zero; Be connected to the drain electrode of a field effect transistor after the anodal parallel connection of the LED fluorescent tube in described every row; Be connected to a driving port that drives chip after the negative pole parallel connection of the LED fluorescent tube in described every row, the driving port of described each driving chip connects the negative pole of the above LED fluorescent tube of row; Described plural driving chip is connected in series, and described first end that drives chip connects the LED control system; The grid of described more than one field effect transistor connects code translator respectively.

Described circuit is provided with inductance, and an end of described inductance connects the power output end of LED control system and the source electrode of more than one field effect transistor respectively, and the other end of described inductance connects the power input of plural driving chip respectively.

Be parallel with first electric capacity between one end of the power output end of described LED control system and inductance, the two ends of described first electric capacity are parallel with second electric capacity; Be parallel with the 3rd electric capacity between the power input of the other end of described inductance and driving chip, the two ends of described the 3rd electric capacity are parallel with the 4th electric capacity.

The drain electrode of described each field effect transistor also connects an end of a resistance, and the other end of described each resistance connects the negative pole of a stabilivolt, the plus earth of described each stabilivolt.

The quantity of described field effect transistor equates with line number in the LED fluorescent tube array arrangement.

The driving port of described each driving chip connects the negative pole of the LED fluorescent tubes of 16 row.

The model of described code translator is 74HC138 or 74HC139.

The utility model adopts above structure, by LED fluorescent tube and the orderly arrangement mode of driving chip, and the driving chip is cascaded, the data source of transmitting when the LED control system outputs to the next chip that drives from first driving chip displacement, the different lines LED fluorescent tube of the driving chip controls same number of rows that is cascaded, reduce sending data line feed number of times, the flicker that has occurred when having alleviated the scanning line feed; Utilize inductance and electric capacity, at first can and drive the chip power supply power supply with the field effect transistor driving power and independently separately not disturb mutually, the interference that the effective filter out power surging of next energy produces, thus reach the influence of eliminating power surging; The driving port shutdown of driving chip can produce some surgings when returning noble potential, the reverse withstand voltage of LED fluorescent tube is 5V, puncture easily, utilize stabilivolt can clamp the voltage of 3.3V, reduce the risk that the LED fluorescent tube punctures greatly, can bleed off the interelectrode capacity on the field effect transistor simultaneously, also can bleed off the distributed capacitance on some passages, in time response LED control system row turn-offs order, can optimize the elimination smear greatly; Above scheme has solved LED display and the secretly phenomenon of bright, smear, interference and shake occurred under high refreshing frequency, make LED display undistorted, do not shake.

Description of drawings

Below in conjunction with the drawings and specific embodiments the utility model is described in further details;

Fig. 1 is a kind of circuit diagram that improves high refreshing frequency LED display stability of the utility model.

Embodiment

As shown in Figure 1, a kind of circuit that improves high refreshing frequency LED display stability of the utility model is electrically connected with LED control system 1, the circuit of the high refreshing frequency LED display of described raising stability is electrically connected with LED control system 1, and described circuit comprises the LED fluorescent tube of an above field effect transistor Q, code translator 2, plural driving chip 3 and array arrangement; The power output end of described LED control system 1 connects the source electrode of more than one field effect transistor Q and the power input of plural driving chip 3 respectively; The LED fluorescent tube of described array arrangement is divided into the capable and m row of n, and wherein n and m are the integer greater than zero; Be connected to the drain electrode of a field effect transistor Q after the anodal parallel connection of the LED fluorescent tube in described every row; Be connected to a driving port that drives chip 3 after the negative pole parallel connection of the LED fluorescent tube in described every row, the driving port of described each driving chip 3 connects the negative pole of the above LED fluorescent tube of row; Described plural driving chip is connected in series, and described first end that drives chip connects LED control system 1; The grid of described more than one field effect transistor Q connects code translator 2 respectively.

Described circuit is provided with inductance 4, and an end of described inductance 4 connects the power output end of LED control system 1 and the source electrode of more than one field effect transistor Q respectively, and the other end of described inductance 4 connects the power input of plural driving chip 3 respectively; Be parallel with first capacitor C 1 between one end of the power output end of described LED control system 1 and inductance 4, the two ends of described first capacitor C 1 are parallel with second capacitor C 2; Be parallel with the 3rd capacitor C 3 between the power input of the other end of described inductance 4 and driving chip 3, the two ends of described the 3rd capacitor C 3 are parallel with the 4th capacitor C 4; The drain electrode of described each field effect transistor Q also connects an end of a resistance R, and the other end of described each resistance R connects the negative pole of a stabilivolt ZD1, the plus earth of described each stabilivolt ZD1; The quantity of described field effect transistor Q equates with line number in the LED fluorescent tube array arrangement; The driving port of described each driving chip 3 connects the negative pole of the LED fluorescent tubes of 16 row; The model of described code translator 2 is 74HC138 or 74HC139; Each drives four LED fluorescent tubes of each drive output connection of chip 3 when LED control system 1 adopts four/one scan mode to design, and each drive output of each driving chip 3 connected eight fluorescent tubes when LED control system 1 adopted eight/one scan mode to design.

It is specific embodiment that the utility model adopts four/one scan mode: described circuit is electrically connected with LED control system 1, and LED control system 1 comprises provides power supply and data source; Described circuit adopts the LED fluorescent tube of four field effect transistor Q, code translator 2, plural driving chip 3 and an array arrangement; The grid of described four field effect transistor connects the code translator 2 that model is 74HC128 or 74HC129 respectively; The power output end of described LED control system 1 connects the source electrode of four field effect transistor Q and the power input of plural driving chip 3 respectively; The LED fluorescent tube of described array arrangement is divided into four lines and m row, described each drive chip 3 and comprise that 16 drive ports, therefore drive chip 3 and be two when above, m just is listed as greater than 32; Be connected to the drain electrode of four field effect transistor Q after the anodal parallel connection of the 4m in the four lines LED fluorescent tube respectively, 16 of described each driving chip 3 drive the negative pole that ports connect the LED fluorescent tubes of 16 row respectively, described plural driving chip 3 is connected in series, described first end that drives chip 3 connects LED control system 1, the data source of LED control system 1 drives chip 3 displacements from first and outputs to the next chip 3 that drives, and the plural driving chip 3 that is cascaded is controlled the array LED fluorescent tube that four lines m row are arranged respectively; The drain electrode of four field effect transistor Q also connects four resistance R, and the other end of described each resistance R connects the negative pole of a stabilivolt ZD1, the plus earth of described each stabilivolt ZD1.

Described circuit is provided with inductance 4, one end of described inductance 4 connects the source electrode of the power output end of LED control system 1 and four s' field effect transistor Q respectively, the other end of described inductance 4 connects the power input of plural driving chip 3 respectively, inductance 4 can be effectively with the power supply of field effect transistor Q with drive chip 3 power supplies and independently separate, do not disturb mutually, eliminate the power surging influence thereby arrive; Be parallel with first capacitor C 1 between one end of the power output end of described LED control system 1 and inductance 4, the two ends of described first capacitor C 1 are parallel with second capacitor C 2; Be parallel with the 3rd capacitor C 3 between the power input of the other end of described inductance 4 and driving chip 3, the two ends of described the 3rd capacitor C 3 are parallel with the 4th capacitor C 4, described first capacitor C 1 and the 3rd capacitor C 3 are low frequency filtering electric capacity, and described second capacitor C 2 and the 4th capacitor C 4 are high-frequency filter capacitor.

Claims

1. circuit that improves high refreshing frequency LED display stability, it is electrically connected with the LED control system, it is characterized in that: it comprises the LED fluorescent tube of an above field effect transistor, code translator, plural driving chip and array arrangement; The power output end of described LED control system connects the source electrode of more than one field effect transistor and the power input of plural driving chip respectively; The LED fluorescent tube of described array arrangement is divided into the capable and m row of n, and wherein n and m are the integer greater than zero; Be connected to the drain electrode of a field effect transistor after the anodal parallel connection of the LED fluorescent tube in described every row; Be connected to a driving port that drives chip after the negative pole parallel connection of the LED fluorescent tube in described every row, the driving port of described each driving chip connects the negative pole of the above LED fluorescent tube of row; Described plural driving chip is connected in series, and described first end that drives chip connects the LED control system; The grid of described more than one field effect transistor connects code translator respectively.

2. a kind of circuit that improves high refreshing frequency LED display stability according to claim 1, it is characterized in that: described circuit is provided with inductance, one end of described inductance connects the power output end of LED control system and the source electrode of more than one field effect transistor respectively, and the other end of described inductance connects the power input of plural driving chip respectively.

3. a kind of circuit that improves high refreshing frequency LED display stability according to claim 2, it is characterized in that: be parallel with first electric capacity between the end of the power output end of described LED control system and inductance, the two ends of described first electric capacity are parallel with second electric capacity; Be parallel with the 3rd electric capacity between the power input of the other end of described inductance and driving chip, the two ends of described the 3rd electric capacity are parallel with the 4th electric capacity.

4. a kind of circuit that improves high refreshing frequency LED display stability according to claim 1, it is characterized in that: the drain electrode of described each field effect transistor also connects an end of a resistance, the other end of described each resistance connects the negative pole of a stabilivolt, the plus earth of described each stabilivolt.

5. a kind of circuit that improves high refreshing frequency LED display stability according to claim 1 is characterized in that: the quantity of described field effect transistor equates with line number in the LED fluorescent tube array arrangement.

6. a kind of circuit that improves high refreshing frequency LED display stability according to claim 1 is characterized in that: described each driving port that drives chip connects the negative pole of the LED fluorescent tubes of 16 row.

7. a kind of circuit that improves high refreshing frequency LED display stability according to claim 1, it is characterized in that: the model of described code translator is 74HC138 or 74HC139.