Rotating LED Array Circuit using IC 555

Rotating LED Array Circuit using IC 555 works like LED flasher and make cool rotating light if LEDs are set right.

This is simple project to make but works good.

We can use this circuit for decoration, emergency light or alert.

This circuit gives two IC 555 pulse signal and LEDs flash in pattern.

The circuit runs on small 3V battery and is for low power use.

Circuit Working:

Component	Value/Specification	Quantity
Resistors (All resistors are 1/4 watt unless specified)
	10k	1
	150Ω	1
	100k	3
	10Ω	12
Capacitors
	Ceramic 10nF	1
	Electrolytic 1µF 25V	1
	Electrolytic 100µF 25V	1
Semiconductors
	IC 555 Timer	2
	LED 5mm,20mA any color	13
	On/Off switch	1
	Battery 3V	1

Circuit use two IC 555 timers and both work as astable multivibrators.

IC1 make clock pulse and control first LEDs like LED1 to LED6 which blink steady.

IC2 get signal from IC1 and make different pulse for second LEDs like LED7 to LED12.

IC1 timing and IC2 timing are not same so they blink different.

Capacitor C3 smoothers the voltage and LED13 with resistor 150Ω is always ON as indicator.

Both timers blink together and make rotating light effect.

Put LEDs on plastic sheet as shown to get the right effect.

The formulas with calculations for Rotating LED Array Circuit using IC 555 is shown below:

IC1 555 frequency:

f = 1.44 / ((R13 + 2×R14) × C1)

Duty cycle D = (R13 + R14) / (R13 + 2×R14)

R13 = 10kΩ, R14 = 100kΩ, C1 = 1µF

f = 1.44 / ((10k + 200k) × 1µF)

= 1.44 / 0.21

= 6.86 Hz blink about 6 to 7 times per second.

IC2 uses same formula with its own R and C values.

To build a Rotating LED Array Circuit using IC 555 following steps are required to be followed:

Pin 1 IC1 connect GND.
Pin 2 IC1 connect Pin 6 IC1.
Pin 3 IC1 to R1 and LED1 cathode, LED1 anode connect positive and same for R2 to R6 with LED2 to LED6.
Pin 4 and pin 8 IC1 connect positive.
R14 connect between pin 6 and pin 7 IC1.
R13 from pin 7 connect to positive.
C1 positive connect to pin 2 of IC1 and C1 negative connect to GND.
Pin 1 of IC2 connect GND.
Pin 2 of IC2 connect to pin 6 IC2.
Pin 3 of IC2 connect R7 and LED7 cathode, LED7 anode connect to positive and same goes for R8 to R12 with LED8 to LED12.
Pin 4 and pin 8 IC2 connect to positive.
R15 from pin 2 IC2 connect to positive.
R16 from pin 6 IC2 connect to GND.
C2 connect between pin 3 IC1 and pin 2 IC2.
LED13 anode connect to positive and cathode connect to R17 and GND.
Switch goes between positive of 3V battery and battery negative goes to GND.
C3+ connect to positive and C3 negative connect GND.

This post for Rotating LED Array Circuit using IC 555 uses easy two IC 555 chips to make LEDs blink and rotate.

Circuit is good for decoration, emergency light and toys.

It works on small battery and looks nice with flashing pattern.