What is a monochrome LED dot matrix display?
What is a monochrome LED dot matrix display?
Excellent LED dot matrix display is a monochrome light-emitting diode in accordance with the structure of rows and columns,according to the size of its internal light-emitting diodes,quantity,luminous intensity,and the difference of luminous color can be divided into a variety of specifications.The 5X7.7X7.8X8 lattice is common.5X7,that is,five LEDs per action,each with a light emitting diode,a total of 35 pixels.The luminous colors are red,green,orange and so on.Figure shows the shape and pin arrangement of the 5X7 series.It consists of 5 high brightness orange red LEDs.Dual in-line 14-foot package.Different types of internal wiring and output pins of different polarity.Figs. 10-7a and 10-7b are two different internal wiring diagrams,which are divided into a common anode structure and a common cathode structure.The common anode structure is that the positive electrode of the light emitting diode is connected to the driving line,and the common cathode structure is that the negative electrode of the light emitting diode is connected with the driving line.The figure in the figure represents the pin number,A ~ G is the row driver, and a ~ e is the column driver.
how to measure the monochrome LED dot matrix display?
Test line, line. Using multimeter or battery can detect the light status of each diode pixel to judge the good or bad.First use the multimeter RX 10k.2 shift to distinguish common cathode and common anode (see LED digital tube detection),and distinguish trip lines and nomads.For the common cathode,the black pen is connected to the column line;for the common anode,the red pen is followed by a nomad.
Discriminating the effect of luminescence (as an example of common anode)
According to the connection of the method in Figure 10-8,figure 10-8a is a short line tube foot detection method,and the short connection of a.b.c.d.e (13, 3, 4, 11, 10, 6 feet) is merged into a leading end E. In the test,the negative electrode of the battery is connected to the E end, and the lead wire is contacted with A, B, C, D, E, F.G (9, 14, 8, 5, 12, 1, 7, 2 feet) in turn,and the corresponding line pixels should light up.For example,when using the positive line to touch 8 feet,the 5 pixels of the C line should also shine at the same time.Figure 10-8b is a short line detection method.The incoming leads A.B.C.D.E.F.G ( 220.127.116.11, 12, 1.7, and 2 feet ) are shorted and combined into a leading-out terminal E.Separate column leads out of the column.When testing,the positive wire is connected to the E terminal,and the negative wire is used to contact the lead wires of a.b.c.d.e.( 18.104.22.168.10.6 feet ),and the corresponding column pixels should be lit to emit light.For example, when you touch three feet with a red pen, the seven pixels of the b column should be illuminated at the same time. When detecting, if one or several pixels do not emit light,the internal LED of the device is damaged.If the brightness is not uniform,the consistency of the device parameters is poor.The performance of a common cathode LED dot matrix display is the same as that of the above method.Just in operation,you need to adjust the positive and negative line position.
Note:test high brightness LED tube should pay attention to the test voltage should be 5 ~ 8V,otherwise it can not light the LED.When testing,if it is determined that one or a row of tubes do not emit light,the outer shell can be disassembled,and the bad pipe is removed,and the same diameter and color of the tube can be replaced,note that the polarity can not be reversed ( see LED digital tube repair ).
What is a color LED dot matrix display?The color LED dot matrix display is a new type of display device,which has the advantages of high density,reliable operation,bright color,etc,and is very suitable to form a color smart display screen.The color LED dot matrix display is based on the rows and columns of the color changing light emitting diodes.Typical product models of domestic color LED dot matrix display are BF430R / G ( 5X7 ).BFJ $ 5OR / G ( 8X8 ).BS 2188 ( 45,8X8R / G ) and so on.3 and 5 of the model indicate the diameter of the discoloration light emitting diode used, OR, R.G.is the abbreviation of the English word,representing three colors of orange red and green respectively.Figure shows the internal circuit diagram of the BFJ5OR / G.This is a common anode lattice display, of which,A ~ H is the line driving line,a total of 8.The row driving lines are divided into two groups,and the orange red ( OR ) and the green ( G ) are each 8.A ~ H represents row pixels,and a ( a' ) ~ h ( h' ) represents column pixels.The principle of light emission can be explained by the color pixels of A row and a column in the upper left corner.A line of orange red light emitting diode is connected with the 22 foot,and the positive voltage is applied between the negative electrode and the 24 foot,and the ( A,a ) pixel is red;when the forward voltage is applied between the 22 feet and 23 feet, the ( A,a ) pixels emit green light;if the forward voltage is applied at the same time, the ( A,a ) pixel can emit the composite light,and the orange is displayed.