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Circuit diagram

This schematic represents a variation of the 10-channel LED driver, incorporating solid-state relays to manage the operation of alternating current lighting. The relay depicted in the diagram is a Radio Shack 3-amp unit (part no. 275-310), necessitating a 1.2 volt DC voltage to initiate activation. Current specifications were not provided, however, it is likely that only a few milliamps are needed to illuminate the internal LED. A 360-ohm resistor is implemented to restrict the flow of current to 17 mA when utilizing a 9-volt power supply. The circuit was evaluated employing a solid-state relay (of an unspecified model) which demanded only 1.5 mA at 3 volts, yet it can function up to 30 volts DC and a significantly elevated current. The chaser sequence can be broadened up to 10 channels through the inclusion of supplementary relays and driving transistors. The 4017 decade counter’s reset line (pin 15) is linked to the fifth count (pin 10) to ensure the lamps sequence from 1 to 4 and subsequently repeats. To accommodate additional stages, the reset pin would be connected to a higher count value.

Solid State Relay

A solid-state relay (SSR) is an electronic switching device that uses solid-state components, such as transistors or thyristors, to control high-power circuits. Unlike electromechanical relays, SSRs have no moving parts, offering increased reliability, faster switching speeds, and longer lifespan. They are commonly employed in applications requiring frequent switching or those sensitive to vibration and noise. This particular SSR operates with a 1.5 mA input at 3 volts, capable of handling up to 30 volts DC and significantly higher current levels, providing a robust solution for controlling AC loads.

4017 Decade Counter

The 4017 is a versatile decade counter IC, a popular integrated circuit used to count from 0 to 9. This IC consists of a binary counter, a flip-flop, and a reset input. The 4017's decade counter is used in various applications, including LED sequencing, digital displays, and control systems. Its reset line (pin 15) is connected to the fifth count (pin 10) to create a repeating pattern, causing the lamps to sequence from 1 to 4 and then loop back to the beginning. The IC's functionality can be extended by connecting the reset pin to a higher count value, allowing for more complex sequencing and timing control.