The S4025L is a Silicon Bidirectional Thyristor (SIDAC) from Teccor Electronics (now Littelfuse). This device is designed for overvoltage protection in various electronic circuits. It is a voltage triggered switch that remains in the on-state until the current through it drops below a holding current threshold. It's a popular option for high energy protection applications.

Applications:

• Overvoltage Protection
• High Voltage Power Supplies
• Gas Discharge Tube (GDT) Replacement
• Solid State Lighting
• Ignition Circuits

Features:

• Breakover Voltage: 37-43V
• Low On-State Voltage: Minimizes power dissipation during conduction.
• High Surge Current Capability: Withstands high current surges without failure.
• Fast Switching Speed: Rapidly switches to the on-state when the breakover voltage is exceeded.
• High Holding Current: Ensures that the SIDAC remains in the on state after triggering.

Benefits:

• Effective Overvoltage Protection: Protects sensitive circuits from voltage surges.
• Enhanced Reliability: Robust design ensures reliable performance in demanding applications.
• Improved System Performance: Fast switching speed enables rapid response to overvoltage conditions.

Additional Details:

The S4025L is available in a TO-220 package. Key specifications include a surge current rating of 25A. The SIDAC triggers when the voltage across its terminals exceeds its breakover voltage. Once triggered, it remains in the on-state until the current falls below the holding current. The device is ideal for protecting electronic circuits from voltage transients caused by lightning, inductive load switching, and other events.