Know all About Programmable LED Firefly Jar

A programmable LED firefly jar is an  inexpensive, fun and exquisite project that makes an excellent gift. Making a programmable firefly jar requires an hour or two hours of time and ever the fan of creative reuse, several of the electronic components will be recycled from old electronics and things around the house. To do this project you would like an Arduino board and soldering experience.

Programmable LED Firefly Jar
Programmable LED Firefly Jar

Programmable LED Firefly Jar Circuit Diagram

The Project had been taken inspiration from Fireflies. This was an innovative idea to design Fireflies in a jar using LEDs, 600mAh 3V CR2450 battery, a custom PCB is used in this project in order to save the cost of the project.

Programmable LED Firefly Jar Circuit Diagram
Programmable LED Firefly Jar Circuit Diagram

The above circuit explains the design of the Jar with Fireflies prepared using LEDs. To start designing the fireflies made from LEDs, the circuit is prepared as shown in the above schematic diagram.

  • R1 – 22.0K Ohm resistor, 3V power supply battery VCC
  • VCC connected to the positive terminal of 3V power supply or battery
  • GND connected to the negative terminal of the battery.
  • The Resistor R1 is to drive the voltage at the reset pin high during operation and is used as pull-up resistor. This stops or safeguards the chip from being reset.
  • The circuit also works if the wire is placed instead of Resistor. R1 is allowed to program the chip to reset the pin not shorting VCC.
  • R2, R3 – 100 Ohm resistors
  • The characteristics of LEDs differ from one LED to another and resistor value will be based on LED type and also the amount of light generated by the LED.
  • The LEDs used in this project have values 20mA at 2.0V and 10mA at 3V through a 100 Ohm resistor. R2 and R3 values were taken larger values.
  • LEDs glow brightly and makes us to feel as real fireflies at 10mA. Scaling in the source code changes the brightness of LED. The LEDs are driven by limiting the software so that it limits the maximum brightness. If you are not aware of this point you will have to change the value of resistors R2 and R3 to determine the exact type of LED that had been used.
  • Assume as PINs – A, B, C, D, E and the Pins are named in source code
  • Let us take A and B Pins as “master” pins. Depending on the source code the LED’s are driven.
  • If any one firefly has to glow in the firefly jar, that particular LED is to be driven and it depends on the choice of master pin we select that may be Pin A or B depending on our choice.
  • If PIN A is selected, then LED1, LED2, or LED3 is driven.
  • If we drive PIN A high, LED2 will be turned ON. If PIN D is driven the pin that the other side of LED2 is connected to) low, while playing the song the LED 2 is turned OFF. The potential difference between the two sides of LED 2 is removed in order to stop the current flowing through it. If the PIN A is driven high always. Two songs are played at the same time when two flies were glowing at the same time as the code is written in this way.

Advantage: These LEDs are energy-saving light bulbs and also due to its optical characteristics, it is optimized in displays for flat back lighting. The other benefit by using LEDs is that they are widely available in the market.

Disadvantage: We are unable to reprogram the chip if it is soldered to the board. This is because the chip programmer cannot drive the reset pin low without shorting to VCC.

Steps To Build a Programmable LED Firefly Jar

To build a programmable LED Firefly jar, there are many steps involves, they are


The Required Components

The required components of Programmable LED Firefly Jar comprise of hardware and software components, such as

Required Components
Required Components
  • An ATTiny85 (tiny based board)
  • Some addressable LED pixels,
  • 1 .10uF capacitor
  • Low value resistor and PCB
  • A 5V wall wart
  • A Jar
  • Diffusive materials like bubble wrap, paint, tissue paper, glass frosting
  • An AVR programmer
  • Breadboard & soldering supplies
  • Arduino, Tiny Core and Adafruit NeoPixel

Software Setup and Test your ATTiny

  • In a software setup, download and install the Arduino, Tiny Core and NeoPixcel Library
  • Setup your ATTiny on the breadboard.

Making a Firefly LED String

In order to prepare firefly LED strings the following steps are followed

LED is prepared using a microclip and the LED is placed on the outside of the pads. LED and Microclip are mounted by putting flux to the pads on the Light Emitting Diode. Now the wires are turned or twisted and are tested after attaching two wires to the LED which gives a nice LED string. From the free end of wire, 2-3mm is stripped and it is tested placing 3 volts through a 100 Ohm resistor. The same process is repeated for each of the 6 strings.

Making a Firefly LED String
Making a Firefly LED String

Red string wires are bundled and soldered to the board. Likewise, six of the LED strings are attached to the board using flux. Red-wire set are carefully soldered to PIN A in a way that the resistor separates the micro controller and the bundle. All other LED strings are soldered in the same way to PIN B. Now in the same way, the green wires flying free are also bundled into 2-wire. By joining green wires together in 2-wire bundles and soldered to PIN C, PIN D and PIN E. Using 3V power all the strings are tested by keeping positive voltage on PIN A or PIN B. The result is obtained if all the LED glows.

Prepare the Jar and Adapter

  • Take one old adapter and cut off the end of the connector, then separate the black and red wires. By using multimeter test the voltage and polarity
  • Poke a hole in your jar lid with a sharp object and thread the cord through.For strain-relief you can tie the cord in a knot.

Solder your components and ATTiny

Solder your ATTiny to a chunk of perfboard. Contain a decoupling capacitor across the power supply and a small value resistor. If you would like your install to be additional versatile install a 8-pin DIP socket so you will be able to take away and reprogram the microcontroller later. Attach the power and ground lines to thread through the jar lid to the present circuit.

Solder the Components and ATTiny
Solder the Components and ATTiny

Assemble the Jar

  • Assemble the jar and distribute your junction rectifier pixels equally.
  • Fill the jar with packing peanuts, bubble wrap, tissue and scrap paper works  nicely and creates some attention-grabbing effects. Reflective plastics and broken glass also can be fun.
  • If you feel very ambitious, you’ll be able to glaze the jar or purchase some paint and use that to present it a lot of semitransparent look.
  • Plug your jar in and revel in the attractive patterns!
Assemble the Jar
Assemble the Jar

Arduino based LED Street Lights with Auto Intensity Control

 White Light Emitting Diodes (LED) replace HID lamps in the street lighting system to include dimming feature. An Arduinoboard is used to control intensity automatically by developing pulse width modulated signals that drive MOSFET(Metal Oxide semiconducto Field Effect transistor) to switch a set of  LEDs accordingly to achieve a desired operation.

This system is built to overcome present-day drawbacks of HID(High Intensity Discharge)lamps. This system demonstrates the usage of LEDs (light emitting diodes) as light source and its variable intensity control, as per requirement.

Arduino based LED Street Lights with Auto Intensity Control Project kit by
Arduino based LED Street Lights with Auto Intensity Control Project kit by

LEDs consume less power and their lifetime is more, as compared to conventional HID lamps Moreover, LED intensity can be controlled as per the requirement during non-peak hours, which is not feasible in HID lamps.
The Arduino board contains programmable instructions that control the intensity of lights based on PWM (Pulse width modulation) signals generated. The intensity of light is kept high during peak hours. As the traffic on the roads tend to decrease slowly in late nights, the intensity also  decreases progressively until morning. Finally the intensity completely shuts down in the morning at 6 A.M, and again resumes at 6 P.M. in the evening and this process is repeated.

This concept in future can be enhanced by integrating it with a solar panel that converts the solar intensity into corresponding power, and this energy is used to feed the highway lights.Furthermore, any queries regarding this concept or electronics projects you can approach us by commenting in the comment section below.

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