788AS 8*8 low price led dot matrix display module Red 16pins

Product Overview

Description

788AS 8*8 low price led dot matrix display module Red  16pins

 

 

Basics

CC means Common cathode       CA means common anode

Dot matrix module, digital tube, and bars are regularly arranged LED (LED light-emitting diode) products, Generally, colors are red, yellow- green, green, yellow, blue and white.

LED's normal operating current is generally 1-20mA, the larger the current the higher the brightness. Brightness required, the current in this range.

Different colors of the forward voltage drop (Vf commonly represented) are different, red, yellow - green, yellow is about 1.8V, green, blue, white, about 3.1V, LED parallel drive voltage constant. For large-size digital tube, LED is connected in series, the number must be multiplied by the total pressure drop led series, namely Vf * N, the driving voltage must be greater than the total pressure drop led to light.

Led drive current limiting resistor should be added protection, current limiting resistor R values determined by the following formula:

R = (Vcc-Vf * N) / I, where Vcc is the supply voltage, Vf for the voltage drop, N is the number of LED in series, I bit operating current (unit A, 1A = 1000mA), such as: Vcc = 5V, Vf = 1.8, N = 1, I = 10mA, then R = 320Ohm, available resistor 330Ohm. If the product is blue, Vf = 3.1V, then R = 190ohm. The actual parameter calculation based on operating voltage and current needs.

LED power Pled = Vf * N * I, the current limiting resistor dissipates Pr = I * I * R, for example, the above example: Pled = 1.8 * 1 * 10mA = 18mW, Pr = 10mA * 10mA * 330ohm = 33mW .

The above are single LED computing, such as the simultaneous need lights N pieces of LED, please * N.

The following is a common LED drive circuit (not prohibited limiting resistor test !! avoid burn LED.