DB3 trigger diode (Diac) is a bidirectional diode which has a two-terminal with asymmetric conductance. It can be used to conduct in both forward and reverse direction. It offers low resistance to current flow in one direction, and high resistance in the other direction. It is a two terminal device so it does not have a gate terminal like Triac to make it start conducting current, so it starts conducting only when applied voltage goes beyond the break-over voltage. DB3 diac is used in rectifier circuits, switching devices, short circuiting protection purposes. The DIACs are used as a trigger device in various applications such as phase control circuits of motor speed control, light dimmers, heat controls, and many other control circuits.

 

Specifications:

• Breakover Voltage (V_bo): 32V
• Output Voltage (V_o): 5V
• Repetitive Peak On-State Current (I_trm): 2.0A
• Breakover Current (I_bo): 0.100mA
• Total Power Dissipation (P_tot): 150mW

 

Product Description

When you start using it, the DIAC will be in blocking state and only very small leakage current will flow. Once the applied voltage reaches the breakdown voltage the resistance of the DIAC drops abruptly and it starts conducting which leads to a sharp decrease in voltage across it and the current starts increasing, called the Conduction State. Most of the DIACs will be having the breakdown voltage around 30 Volts. If you want to turn the DIAC off, it will remain in the conducting state until the current reaches the particular value called the holding current, where holding current is the minimum current that required for a device to keep it in the ON state and if the current fall below this level then it DIAC will stop conducting.

 

Additional Resources

DB3 Datasheet

 

Package Contents

1×DB3 Trigger Diode