NPN Transistor BC337 (BJT)

🔋 BC337 – NPN Bipolar Junction Transistor (BJT)

The BC337 is a general-purpose NPN transistor used in a wide range of switching and amplification applications. With a collector current of up to 800mA, it is ideal for driving relays, LEDs, motors, and small audio or signal amplification in Arduino, ESP32, or other microcontroller projects.

⚙️ Technical Specifications

📎 Pin Configuration (TO-92)

   FRONT VIEW
   _______
  |       |
  |       |
  |_______|
   | | |
  C B E

• C – Collector

• B – Base

• E – Emitter

✅ Features

• ⚙️ General-purpose NPN transistor

• 🔌 Suitable for switching applications (up to 800mA)

• 🔊 Can be used in audio amplification circuits

• 🧩 Compatible with Arduino, Raspberry Pi, and DIY electronics

• 🛠️ Easy to prototype on breadboards or PCBs

🧪 Example Application: LED Switching

Wiring:

• Connect emitter to GND

• Connect collector to LED (and then to resistor + Vcc)

• Connect base to Arduino pin through a 1kΩ resistor

Arduino Code Example:

cpp
CopyEdit
int ledPin = 3; // Connected to base via 1k resistor

void setup() {
  pinMode(ledPin, OUTPUT);
}

void loop() {
  digitalWrite(ledPin, HIGH); // Turns LED ON
  delay(1000);
  digitalWrite(ledPin, LOW);  // Turns LED OFF
  delay(1000);
}

🎥 YouTube Tutorial