Sunday, May 29, 2016

Controlling Multiple LEDs

Multiple LED Control Using Minimum I/O pins



A truth table for controlling six LEDs using three I/O is shown below:


H = Output Set high (5V)
L = Output set low (ground)
I = Input

More LEDs can be controlled by using this equation:
Numbers of LEDs = (Numbers of PINs) x ( Numbers of PINs – 1)

For example:
Number of LEDs = 4 x (4-1)
                        = 4 x 3
                        = 12 LEDs

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