This circuit uses digital circuits such as a demultiplexer and a binary counter to create patterns of “moving” led lights. This basic circuit is really cool when used in the dark or to light up a sign of some sort, as it creates a cool pattern that catches the eye.
The speed of an automobile can be indicated by detecting the pulses generated by the ignition system and causing an LED to light.
The bi-directional sequencer uses a 4 bit binary up/down counter (CD4516) and two “1 of 8 line decoders” (74HC138 or 74HCT138) to generate the popular “Night Rider” display.
The circuit below uses a hex Schmitt Trigger inverter (74HC14) and two 8 bit Serial-In/Parallel-Out shift registers (74HCT164 or 74HC164) to sequence 16 LEDs.
This circuit provides a visual 9 second delay using 10 LEDs before closing a 12 volt relay.
The Display is an array of 5×24 Leds. I used Shift registers to light up every column, DO NOT USE ANY 74LSXXX TTL. The 74LS is a Low Power TTL that doesn’t light up the leds very well. Use the 74HCXXX series or 74FXX series.