Introduction
In our day to day life, we are constantly controlling different kinds of lights, AC/DC motors and many more appliances. Sometimes we are using low level voltage to control high voltage loads. This is particularly seen while controlling loads using a microcontroller. Since microcontroller are designed to be more power efficient and low power consumption is a key aspect. So, the logic level for microcontrollers is usually 5V or 3.3V DC. To control high voltage loads, we can use a suitable transistor where the low amount of driving current can be used to drive heavy loads. Since the current flow through the BJT transistors depend on the base current, we can control the flow of current of the base by varying the base resistance using a potentiometer. Hence the load current can be varied in this way. So, in this tutorial, we are going to demonstrate how to make a circuit using a BJT transistor to control the brightness of high-power LED Strip using a very low power control signal.
Best Use Case
- Adjustable home lighting
- Energy-efficient lighting systems
- Customizable lighting setups
- Dynamic brightness control
- Remote lighting management
Required Components
- BC363 and BC39 BJT Transistors
- DC LED Strip Light
- Potentiometer
- Resistors
- Switches
- Breadboard or Veroboard (Optional: PCB)
- Connecting wires
- 12V and 5V Supply
Circuit Diagram
Instructions
The hardware setup should be made according to the above diagrams. The circuit can be implemented on a breadboard or on a Veroboard for proper connections. Even better, the whole circuit can be implemented on a PCB using the layout design file from the files section of this page. After the setup is made, we need to just turn on the power switch. Afterwards, we can now control the brightness of the LED strip rotating the potentiometer. In this demonstration, the load’s power consumption is comparatively high than the driving signal. But in case you wish to drive even higher loads, you need to opt for more powerful BJT transistor, use heatsink is necessary and calculate the resistance value accordingly.
