DB3 – Bi Directional Diac

The DB3 is a bidirectional DIAC (Diode for Alternating Current) commonly used in triggering TRIACs for AC switching applications like dimmer circuits, motor speed control, and power regulation.

⚡ Specifications:

• Breakover Voltage (V_BO): 30V – 40V
• Breakover Current (I_BO): ~0.5mA
• Holding Current (I_H): ~5mA
• Maximum Voltage: 32V (typical)
• Maximum Current: 2A (pulsed)
• Package: DO-35 (small diode-like package)
• Bidirectional Operation: Works in both AC half-cycles

🔌 How It Works:

1. Below 30V: The DB3 remains OFF, acting as an open circuit.
2. At 30V – 40V (Breakover Voltage): The DIAC conducts, allowing current to flow and triggering the TRIAC in an AC control circuit.
3. Below Holding Current (~5mA): It turns OFF until the voltage reaches breakover again.

📌 Applications:

✅ TRIAC Triggering (dimmer circuits, fan regulators)
✅ AC Motor Speed Control
✅ Light Dimmers
✅ Heater Control Circuits
✅ Oscillator Circuits