At this time, I made 3 X 4 (= 12 pcs ) LEDs room light.


- Tools and Parts needed -
A) LED ( I used "NICHIA" LED. It is 5mm (diameter) white LED. Part number is NSPW-500BS rank b, 3.6V 20mA )
Q'ty : 12 pcs.
This LED is very bright ! But the directivity is very narrow. ( Direction Characteristics : 20 degrees )

B) CRD ( CRD = Current Regulating Diode. 25V. 15mA )
Q'ty : 4 pcs
The voltage of car is unstable, as you know. This CRD helps brightness to be stable.

C) The existing room light
Q'ty : 1 pc
You do not need to use it. ( I used the terminal of both ends. )

D) Universal circuit board
Q'ty : 1 pc

E) Soldering iron, solder, sand paper and universal tools


- About LED -
LED is Light Emitting Diode. That is to say, it is diode. :D Therefore, there is direction, as you know. If you connect opposite, LED does not operate.:-(
Regarding this LED, short line is minus (cathode ). (The long line is plus. ) Also, LED is sensitive to static electricity. So please treat carefully.


-Let's go do it ! :D-
As you can see the rough sketch, connect 1 CRD and 3 LEDs ( total 4 sets ) on the circuit board.The length of board is slightly smaller than the existing room light.



Solder all LEDs and CRDs. After that, connect the terminals of the existing room light ( both ends ). Sorry, I cannot explain details ! Please see below !! :D


I also scraped the tip of the LED because the directivity of this LED is very narrow. If scraped off, light illuminated a large area.


Turn on !! :D

LED always lights up immediately. It is very interesting !

Why did I do that ?? I do not know !! But I have a feeling of satisfaction !! :D

Currently, there are many LED products at stores. Therefore, maybe, I think you do not need to make it !