Transistor switch circuit for Raspberry Pi, Arduino and micro:bit

This video shows a practical example of using a transistor switch. It is a switch to control a large bright LED using a Raspberry Pi, Arduino and micro:bit.


The first example uses a transistor switch to control a large bright LED from a Raspberry Pi. The circuit can also be used with the Arduino and Micro:Bit especially if you increase the number of LEDs being switched.

The second example features a darlington transistor used to switch a much larger light. This uses 2.5W LED lights from PoundLand

These are based on circuits from my book Learn Electronics with Raspberry Pi (2nd edition) http://www.penguintutor.com/projects/...


For future ideas you may want to look at the following project which also uses a PIR sensor:
http://www.penguintutor.com/electroni...


Chapters:
00:00 Introduction
01:05 What is a transistor?
02:29 Transistor packages
03:23 Transistor connections and operation
04:23 Introduction to the LED demonstration
05:20 Schematic diagram of transistor switch circuit
05:55 Choosing a transistor and looking at datasheets (2N2222A)
07:04 Calculating the resistor values
11:45 Breadboard circuit using the Raspberry Pi
12:25 Adding a second LED in parallel
13:46 Raspberry Pi code - Python gpiozero
14:26 Arduino Code - C++ - blink.cpp
14:48 micro:bit - MakeCode block based code
15:07 microbit - Javascript code
15:20 Demo of LED transistor switch
16:03 Poundland USB light bulbs
16:32 Darlington Pair / Darlington Transistor BD681
17:09 Circuit diagram for Raspberry Pi Darlington Transistor
19:07 Demonstration of Darlington Transistor switch
19:52 Darlington transistor array ULN2803A
20:30 Summary