Simple Alternate LED Flashing Using 555 Timer

Introduction: Simple Alternate LED Flashing Using 555 Timer

About: electrical and electronics engineering student

here is the circuit diagram.!

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Step 1: Components Required

1) 2 led of different colours
2) 100uf capacitor
3) 555 timer ic
4) wires
5)9v battery
6) battery connector
7) 1 k ohm resistor 1
8) 10 k ohm resistor 1
9) 220 ohm resistor 2
10) bread boaed

Step 2: Connecting the Components

1) mount the 555 ic in the middle of the bread board
2)connect pin no 7 and 8 with 1 k ohm resistor
3) connect pin 6and 7 with 10k ohm resistor
4)join 2nd and 6th pin
5) join 4th and 8th pin
6) connect pin 1 and 2 with the capacitor
7) take a separate line from the pin 3 and connect one of the 220 ohm resistor to it, and connect the anode(+) of one of the led to the other end of the resistor and connect the cathode(-) of led to pin no 2.
8) connect the anode of another led to pin 4, then connect the another 220 ohm resistor series with it
9)connect the another end of the resistor to pin no 3

Step 3: Testing

connect the positive end of the battery to pin no 8 and negative to pin no 1.
You will see the LEDs flashing alternatingly... plz try this @ home it will cost below 2$.

hope you guys like this..
comment your doubts below
thank you..! meet you all soon with another circuit..


2 People Made This Project!


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6 Discussions


3 months ago

Thanks! Will be trying to make it soon!


Question 2 years ago on Step 1

Could this circuit be connected to a 12v supply?


Question 2 years ago

And can this circuit be connected to the main (220v) voltage using resistors and diodes without a transforme?


Question 2 years ago on Step 3

What are the polarity of the capacitor (to what pin we connect the capacitor +ve pole ?


Question 2 years ago on Introduction

What is the voltage of the 100uf capacitor and the wattage of each resistor of the circuit?


4 years ago

this is what ive been looking for, what is the time interval of the two leds blinking? and if i want to slower the time should i raise the amm=ount of resistor? to what cvalue? thanks