8 LEDs using shift register (2014)
I liked the car Pontiac since I was a little child. This car can be seen in series Knight Rider with a line of red light in the front. This influenced me to build a simple board with shift register to control 8 LED lights. The functionality of the shift register is described on the following page Shift Register (2014).
I chose 74HTC595 as shift register. This chip is CMOS compatible and provides enough current to power diodes. The next advantage lies in storage register. Data are pushed to this register after they are fully loaded. The diodes thus do not blink during loading the value.
Each diode is prepended with a resistor in order to limit the maximal current that can flow through the 74HTC595 chip. I chose 560 ohms resistors. The board is controlled by three signals: clock, data and storage. It is necessary to keep minimal timing given by the manufacturer.
Diodes are fixed in a Lego Technic piece. Since I had no piece of length of 8, I manufactured it by myself. I had to use a drill to enlarge the holes in the Lego piece in order the diodes fit inside.
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Source codesClick the label to show the source code
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