FLASHLIGHT

Week 01 | 09/02/2022

Battery and LED

Portable, simple, small light, easy to carry, functional — these are the goals for the flashlight project.

I listed all the absolutely necessary items: a battery, a resistor, a LED and some wires. Switch is nice to have, but not 100% needed. Figure 1 shows all the parts that the project needs, which all are taken from the shop besides the battery. The shape of the 9V battery is unique and stable, which is perfect to be the stand of the flashlight while providing long-lasting power for the LED.

figure 1 - parts

figure 2 - poke LED through the 9V connector

figure 3 - front view

figure 4 - using the gap between the connectors

figure 5 - a 220-ohm resistor is added

figure 6 - make it tidy

figure 7 - it works

figure 8 - detail

figure 9 - version II: a switch is added

figure 10 - detail

This is a fun exercise, especially for the ones who have never had any electrical experiences. As stated, the goal is to make the flashlight as simple as possible, so I personally prefer the one without the switch, which provides the “plug and go” capability.