The S4008R is a silicon controlled rectifier (SCR) from Littelfuse Inc., designed for various switching and control applications. SCRs are semiconductor devices that act as switches, controlling the flow of current in a circuit. The S4008R is known for its robust performance and reliability in handling high voltage and current.

Applications

• Motor control
• Phase control
• Lighting control
• Voltage regulation
• Solid-state relays

Features

• High surge current capability
• High blocking voltage
• Glass passivated junction
• High reliability
• Sensitive gate triggering

Benefits

• Efficient control of AC power
• Protection against overvoltage and overcurrent
• Long-term reliability in demanding environments
• Easy triggering with low gate current
• Enhanced system safety

Detailed Specifications

The S4008R features a repetitive peak off-state voltage (VDRM) and repetitive peak reverse voltage (VRRM) of 400V. It has an on-state current (IT(RMS)) rating of 8A. The surge current capability (ITSM) can reach up to 80A. The gate trigger current (IGT) is typically around 200 μA. It comes in a TO-220 package, suitable for heat dissipation.

The high surge current capability allows the SCR to withstand transient current spikes without failure, making it suitable for applications with frequent inrush currents. The high blocking voltage ensures that the SCR can block high voltages when in the off-state. The glass passivated junction enhances the SCR's reliability and stability under high-temperature conditions. The sensitive gate triggering allows the SCR to be easily triggered with a low gate current, simplifying the driving circuitry.

In summary, the S4008R is a robust and reliable SCR suitable for a wide range of power control applications. Its high surge current capability, high blocking voltage, and sensitive gate triggering make it a cost-effective solution for controlling AC power in demanding environments.