I was spoiled by other cheap battery-operated irons that had LEDs so I decided to add a pair of spare 5mm white LEDs to Pinecil iron. I had them from a reverse backup camera and they were already prewired with a thin wire.
- Vcc can be easily tapped from the leg of capacitor C8 or inductor L1. (Vcc measured 4V for my Pinecil.)
- I added a 22 Ohm resistor to achieve about 22mA per LED: (Rs = (Vbus-Vf)/If = (4V-3V)/20mA = 40 Ohm. )
- I positioned the resistor right above the tip core and glued it to the ground tab while avoiding making short anywhere (use insulation)
- LED anode (+) is soldered to the resistor and cathode (-) to the ground tab.
- I drilled two small holes under the rubber sleeve for the cables and 3Dprinted a bracket to position the LEDs. Here is the file in Fusion360 (with Manufacturing Environment for slicing and final tolerance adjustments )
- Final result:
- Vcc can be easily tapped from the leg of capacitor C8 or inductor L1. (Vcc measured 4V for my Pinecil.)
- I added a 22 Ohm resistor to achieve about 22mA per LED: (Rs = (Vbus-Vf)/If = (4V-3V)/20mA = 40 Ohm. )
- I positioned the resistor right above the tip core and glued it to the ground tab while avoiding making short anywhere (use insulation)
- LED anode (+) is soldered to the resistor and cathode (-) to the ground tab.
- I drilled two small holes under the rubber sleeve for the cables and 3Dprinted a bracket to position the LEDs. Here is the file in Fusion360 (with Manufacturing Environment for slicing and final tolerance adjustments )
- Final result: