YAFLC (Yet Another Flickering LED Candle) using Tiny45 microcontroller

Nov 5, 2012 by

There are numerous posts on Instructables about how to make a flickering LED candle. This is my version.

The project requires the following components:
1. Tiny45 AVR Microcontroller (Tiny13 would also do)
2. 1W Warm white (or yellow) LED
3. Perspex tube
4. AA or AAA size batteries- 4 (alkaline or NiMH)
5. PCB stock (or a general purpose veroboard)
6. Battery holders
7. 1/4W resistors 50 Ohm- 4 and 10K -1.
8. On/Off switch
9. Connecting wire
10. piece of wood for the base
11. masking tape

1. Solder iron and solder
2. Hot glue gun
3. AVR ISP Programmer
4. screwdriver, files, drilling machine and suitable drilling bits.

Step: 1 The circuit diagram

The circuit diagram

The required circuit diagram for the candle is here. Also seen is the board layout. In the board layout, the blue tracks are handled as jumper wires. The complete circuit is split in two boards, one containing the controller and the has the 1-W LED. The two boards are arranged in a double-decker, circular PCBs. The idea is to have a smaller total diameter for the circuit. four 2-pin connectors are used to connect the controller board to the LED board. The fifth connector on the controller board is for the power supply.

Step: 2 Making the PCBs

I used Modela Milling machineModela Milling machine to mill and cut my boards. You can get these boards fabricated from commercial PCB manufacturers such as PCB ExpressPCB Express or you can even make them at home as described herehere.

Step: 3 Soldering the PCBs

Soldering the PCBs

I soldered all the components as seen in the photographs. By distributing the circuit on two boards, one for the controller and another for the LED is not only useful in reducing the diameter of the board but also to ensure that when the controller board is programmed through the ISP connector (by first disconnecting the LED board from the controller board), the LED does not load the ISP signals.

I soldered all the SMD components first, followed by the jumper wires and then the rest of the components.

Step: 4 Prepare the LED board

After the LED board is soldered, I used hot glue gun to pour some glue on the LED. As the hot glue begins to cool, I draw the glue out as a sort of a ‘wick’. The glue serves two purposes: it diffuses the light and the ‘wick’ gives a feel of a real candle.

Leave a Comment

You must be logged in to post a comment.

Recent Posts

I2C Bus for ATtiny and ATmega

I2C Bus for ATtiny and ATmega

I love the Atmel AVR microcontrollers! Since building the Ghetto Development System described in thi[...]
Interfacing GY 26 with atmega640

Interfacing GY 26 with atmega640

Hello friend once again with new instructable in this I will show you how to interface GY 26 with UA[...]
Using Atmega32 with Arduino IDE

Using Atmega32 with Arduino IDE

Over time I have used all kinds of Atmel microcontrollers in various projects. One of the mos[...]
Standalone Arduino / ATMega chip on breadboard

Standalone Arduino / ATMega chip on breadboard

Step 1: Parts needed I bought my parts from Digikey and Sparkfun Electronics - they're 2 of my favo[...]
Burning atmega328-pu and atmega328p-pu bootloader

Burning atmega328-pu and atmega328p-pu bootloader

Burning the boot loader in an atmega328 could be somewhat tricky but if u follow these steps correct[...]

Read more:
SoftControl wins Service Contract for Arrow Electronics’s Computer Network Operations