## Introduction: Using LEDS and AT Tiny to Create a Blinking Star With Piezo Playing " Twinkle, Twinkle, Little Star"

This circuit uses LEDS ,AT TINY and piezo to produce a blinking star and music of "Twinkle, Twinkle ,little star" Please see the next step for the and circuit overview.

## Step 1: Circuit Overview .

This circuit consists of LEDS ,ATTINY (2) and a piezo and Arduino .The Arduino will supply the power and the LEDs will light up with resistors .The ATTiny will blink some of the LEDS .The piezo speaker will play "Twinkle,Twinkle,little Star ' will a Code .

## Step 2: LEDs

There are LEDs in this circuit .The LED stands for light emitting diode.

The LED consists of semiconductor crystal(p-type and n-type).If the crystal is energized by a current the semiconductor emits light .

There are important consideration in using the LEDs.LEDs work in one direction only,Current goes from the positive side(anode) to the negative side (cathode).It is important to use a resistor to regulate the current .The LED has a current limit of 20 mA per LED.

The short leg of the LED is the cathode (negative) .The longer leg of the LED is the anode (positive ) lead .

Always connect a resistor to the anode (positive) lead and the cathode (negative) lead to ground .

The symbol and picture of the LEDs are above .

## Step 3: The AT TINY

The AT TINY is a microcontroller chip .Microcontroller are used in circuit to do one function .

Many electric devices use microcontrollers like microwaves, mixers etc.

The AT TINY is being used here as a clock .We will connect the LEDs to the ATTINY(pin5) which will give a clock input .A clock input is a series of pulsed inputs .This will make the LEDs blink.

## Step 4: Electronic Components Used in the Circuit

Arduino Uno

15 LEDS

2 AT TINY 85 chips

12 ; resistors(yellow,violet ,brown)

piezo speaker

wires

## Step 5: Piezo Speaker

The piezo speaker is the larger round object above in the image .

The piezo speaker consists of piezo crystal which is between 2 crystals .When voltage is applied across the crystals,they push the one conductor and pull the other .This action of pushing and pulling conductors produces sound .

The Code is read by Arduino and produces the notes for the song "Twinkle,Twinkle, little star'.

Note the positive lead of the piezo is connected to Arduino digital pin 11 .The negative lead is connected to ground on the digital rail of the Arduino .See image.

## Step 6: Conclusion

This projects shows how you can use LEDs,ATTINY and resistors to create a circuit with LEDs to form a blinking star .Also it shows how the piezo can produce the notes of the song "Twinkle,Twinkle, little star ".

I made this circuit on Tinkercad .It was tested and works .

I hope this projects helps you to understand LEDS,AT TINY and piezo speakers and how they can be used to created a visual and musical circuit .

Thank you