Microcontrollers are an intriguing and critical part of today’s electronics. With the ever-growing field of electronics, it has become impossible to be an electronic system engineer and not have to meddle with microcontrollers. But the general issue that comes with using many different controllers is that each controller may require a different voltage level to operate safely. So, in this project, we are going to build a comprehensive Essential Power Supply Circuit For Arduinos & Other Microcontrollers.
At the core of this essential power supply, this circuit serves as a base supply for microcontrollers that operate in the standard DC range (12V, 9V, 5V, 3.3V). This circuit employs a combination of regulators namely an LM2940CT-12.0 for providing uninterrupted 12V DC output & LM2940CT-9.0 for a 9V DC output. Along with these 2, the circuit utilizes an LM2940CT-5.0 & an LM1086-3.3 For the provision of 5V and 3.3V DC Supply respectively.
Hardware Components
The following components are required to make Power Supply Circuit
| S.no | Component | Value | Qty |
|---|---|---|---|
| 1 | Voltage Regulator ICs | LM240CT-12.0, LM240CT-9.0 , LM240CT-5.0, LM1086-3.3 | 1 |
| 2 | Input DC Supply | 15V/1.5A – 2A | 1 |
| 3 | DC Power jack | 3.5mm (male/Female) | 4 |
| 4 | Electrolytic Capacitor | 10uF/50v, 100uF/50V | 8 |
| 5 | Heat Sink (optional) | – | 4 |
| 6 | Breadboard | – | 1 |
| 7 | Battery clips | – | 1 |
| 8 | Connecting Wires | – | As per need |
LM2940CT Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of LM2940CT
Power Supply Circuit
Working Explanation
The main aim of this circuit is to function as a comprehensive & versatile power supply for various controllers. the working of this circuit is very simple, a input DC signal of 15V/1.5A – 2A serves as the input to this circuit. This signal parallelly distributes to smoothing capacitors (10uF) of each supply circuit, in order to remove any residual noise. The corresponding DC signal then moves to the regulator IC of each supply circuit.
The regulator module ensures a regulated voltage level (12V, 9V, 5V, 3.3V) while maintaining a constant current output. The output DC signals pass through a 100uF smoothing capacitor, before moving on towards the output.
Applications
- Normally, serves as a fixed bench supply for various controllers such as Arduino UNO, Raspberry Pi, Teensy 2.0, etc
