LED Flash Light Badge

Are you new to Soldering and want to learn basics with a simple kit ?

If you are looking for an easy way to learn soldering or just want to make a small portable gadget, This LED Flash light badge is a great choice. This LED Flash Light Badge PCB is designed to learn the soldering .

Features:

• Simple design and Low parts count
• Easy to change the CR2032 battery
• Quick to assembly
• A personal emergency flashlight 🙂
• Perfect to have for power outage

A Few Project Goals:

• Implement the Circuit myself.
• Design a PCB.

This kit Contains :

• 5 mm white LED
• 6mm Momentary Mini Push Button Switch
• 10 ohm resistor
• CR2032 Battery Holder and CR2032 Coin cell Battery
• Custom PCB : From pcbway.com (if you would like to buy this PCB Badge, you can buy it from pcbway’s Shared projects page) .

Schematics:

I know … he is going to explain the boring theory………………….

Picking Best LED and Resistor combo …

LEDs have forward voltage .This is the minimum voltage necessary to turn the LED on .As per datasheet forward voltage value VF,was 2.8 Volt.And Current through the LED (I_LED) is 20 mA (0.02A).

V_S is the source voltage, That is 3.0 Volt. i.e. CR2032 Coin cell Battery Voltage

According to ohm’s law

V = I*R or voltage equals current times resistance

The V in our formula is found by subtracting the LED’s forward voltage from the voltage of the power supply.

V =V_S – VF

=3 – 2.8 = 0.2 V

So, 20 mA is the “desired” current— what we’re hoping to get when we pick a resistor, and also the I_LED that we’ll plug into our V = I × R formula.

0.2 V = 20 mA × R

or

0.2 V / 20 mA = R

when we solve it , we get :

0.2V / 20 mA = 0.2 V / 0.02 A  =  10 Ω

Our version of the formula now looks like this:

(Power supply voltage – LED voltage) / current (in amps) = desired resistor value (in ohms)

if you look at chart for common resistor values, you can find 10 Ω resistor out there .

If the calculated value is not available ,choose the nearest standard resistor value which is greater ,so that the current will be a little less than you chose.In fact you may wish to choose a greater resistor value to reduce the current (to increase battery life for example) but this will make the LED less bright.

The board outline were made using Autodesk Fusion 360.And PCB design was done using KiCad.

I went to PCBWAY website and I uploaded my board to their platform.There are lot of options to chose but ,set everything to the default except the color of the PCB.

I like black Solder mask !

Pcbway offers incredible quality and quick turnaround at very low prices.

The first impression are good after unpacked and unwrapped.The boards looks good ,the solder mask is bright and silkscreen is reasonably legible.I was super happy with pcbway’s service.There were no complications,no delays and everything worked exactly as expected.

If you have your own project and you need good quality PCBs,Consider using the service of PCBWAY.

The Soldering Time !

Conclusion:
From initial idea to final assembly ,this project took about 2 weeks time. Total build time for assembly was around 10 minutes .

All the Project files are up on Github, go make !

Do you have any questions ? Leave a comment down here .

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Updates:

• 04/05/2020 : LED Flash Light Badge Certified by OSHWA

Reference links: