# Led and small push button for doll house how to make it work

I am bulding a doll house with electricity, using led as ceiling light and small push button as light switch, I know nothing on how to make this work, do I need a batery 9 v to connect that to , I need help

Hello @Alait and welcome to the RobotShop community!

Yes, you need a battery to power the LED and you will probably need a resistor to limit the current draw and avoid burning your LED. The wiring diagram is a simple as this:

Or you could even use a potentiometer to dim the light:

https://learn.sparkfun.com/tutorials/light-emitting-diodes-leds/all

Let us know if you need further assistance

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I like smart people lile you, do pĂ©pĂ© want to put led inside tje doll house he is building for his grand daughter and he bought on this site the mini push button switch RB -Spa-191 and LED RB-Dfr-394

To make this work, what size of wire shoĂ»d I be ordering, I need 1 resistance 220 ohm for each LED and do I need a connecting bord or can it be connected directly?

Thanks in advance for you brilliant assistance, a 5 years old girl will be so happy of the result

Thanks, @Alait!

Note that the RB -Spa-191 is a push button so it works as a momentary switch, which means that it only works â€śmomentarilyâ€ť while is being pressed (like a doorbell), you will need an on/off rocker switch if you want to use it as a light switch.

The size of the wire is not very important, just use one that works for your setup. If you are going to use a 9V battery you will probably need higher resistance values to limit the current.

The LEDs you linked have the following specs:

• Voltage:1.8-2.2V(Basic Red,Green,Yellow)
• Voltage:2.4-2.7V(White,Blue)
• Max current: 20mA
• Suggested using current: 16-18mA

If we use this formula:

we get:

R = (9V - 1.8V)/0.016 = 423 Ohms so you could use 470 resistors.

And you donâ€™t need a board to connect them, just the LEDs, the resistors, some cables, the rocker switch, the battery, and you could use some electrical tape to connect the LEDs to the wires or simply wrap the cable around the â€ślegsâ€ť.

Is their such thing as an on/off switch of the same size of the spa-191 like the ones that I bought? I intended to integrate them into the wall (10mm plywood) neer each door of the doll house to turn on/off the LEDs of each room, the switch you identified seems to be a little bit to large

Maybe one of these could work for you:

But you can also find some other options searching for â€śSwitchâ€ť in the store, and donâ€™t get scared of the SPDT, DPDT words, you can see how those switches work in this video:

You could also be interested in something like this:

I hope the project is complete by this time. You can post your progress here if you wish.