Tap Light LED Auto-Off Hack

Step 6 Wiring up the circuit

Wiring up the circuit doesn't require a PCB board, although I guess you could get a small one in this tap light if you wanted to. In the pictures below, I've outlined the process I used step by step and it was brain-dead easy.

DataSheet for my 2N7000 mosfet. Verify with your particular part's datasheet.

1. Connect the mosfet to and you capacitor together. I've trimmed the length of the legs on the capacitor a bit and pre-tinned the legs of all parts. Make sure the negative leg of the capacitor is connected to the source leg of the mosfet and the positive leg of the capacitor to the gate of the mosfet . (image 1)

2. I only had 1M ohm resistors laying around so I soldered two of them in series and trimmed the legs. (image 2)

3. Connect the resistors to the source and gate of the mosfet just as we did with the capacitor. You don't have to worry with polarity with the resistor. (image 3)

4. Solder the wire we previously soldered to the cathodes of the LEDs to the drain of the mosfet. (image 4)

5. Solder the positive wire from the switch to the gate leg of the mosfet. (image 5)

6. Solder the negative wire from the batteries to the source leg of the mosfet. (image 5)

Now, VERIFY every connection and ensure you have no shorts, bridges, etc! Once you have done that, do it AGAIN!