My first electronics project in over a decade involves a Raspberry Pi 3 and two illuminated buttons. I want to understand what resistor I need for the LEDs, if any.
The illuminated buttons have three pins which I believe are:
- +12 V
- 0 V
Configured this way, the LED is permanently lit. If I switch pins 1 and 2, the LED lights when the button is pressed, but I don't know how this affects the signal. Could I simply switch them?
The LEDs are rated for 14V and a continuous 10A. The salesman convinced me that a Raspberry Pi would be fine with these specs. I have confirmed with a power supply that 3.3V is sufficient to light the LED.
Given the LED has such a high tolerance compared to what a Raspberry Pi can supply, do I need a resistor, and if so, how do I determine which one and which pin do I attach it to?
EDIT: The project is to create a Big Red Button™ that when pressed, activates Find My iPhone, Play Sound on my wife's phone. It's a daily necessity. Ideally I'd like full control over the LED to use it for feedback, but if that's a risk to the Raspberry Pi I'll settle for lit when pressed.