S4003LS2

Overview

The S4003LS2 is a silicon-controlled rectifier (SCR) manufactured by Littelfuse Inc., designed for high-voltage power control applications. It features a 400 V repetitive peak off-state voltage and supports an average on-state current of 3 A. The device utilizes a sensitive gate structure, requiring a maximum gate trigger current of 200 µA and a maximum gate trigger voltage of 800 mV to initiate conduction. It is housed in a TO-220-3 isolated tab package suitable for through-hole mounting. Key electrical characteristics include a holding current of 6 mA and a non-repetitive surge current rating of 50 A at 50/60 Hz. The component operates within a junction temperature range of -40°C to 110°C.

Feature Summary

• Sensitive gate architecture enables reliable triggering with low input drive requirements.
• Isolated tab construction facilitates secure mounting to heatsinks while maintaining electrical isolation from the circuit ground.
• Robust surge current handling capability provides protection against transient overcurrent events.

Applications

• AC motor speed control circuits
• Solid-state relay designs
• General-purpose AC power switching

Procurement Notes

Verify the specific suffix designation when ordering, as packaging variations such as tube or tape-and-reel configurations may exist within the product family. Confirm compliance with RoHS directives and REACH SVHC requirements prior to integration. Ensure that the selected distributor source provides authentic Littelfuse components to guarantee performance reliability and traceability.

Selection Notes

Select this component when a 400 V blocking voltage and 3 A continuous current capacity are required. The sensitive gate characteristic simplifies driver circuit design compared to standard gate devices. Verify that the thermal management solution can handle the power dissipation associated with the specified load conditions and ambient temperatures.

Part Context

This SCR belongs to the Sxx10xSx series, which includes various voltage and current ratings within the same package footprint. The LS2 designation typically indicates a specific pin configuration and isolation feature common to Littelfuse's TO-220 thyristor lineup. It serves as a discrete alternative to integrated power modules in cost-sensitive industrial applications.

Replacement Considerations

Direct parameter-equivalent replacements include the S4006LS2TP and S4008LS2TP, which offer higher current ratings but share similar voltage and package specifications. Verify that any substitute maintains the sensitive gate requirement and TO-220 isolated tab form factor.

FAQ

What is the maximum gate trigger current for the S4003LS2?

The maximum gate trigger current is 200 µA, classifying it as a sensitive gate SCR.

Does the S4003LS2 provide electrical isolation between the terminal and the mounting surface?

Yes, the TO-220-3 isolated tab package ensures electrical isolation between the main terminal and the heatsink mounting area.

What is the non-repetitive surge current rating?

The device supports a non-repetitive surge current of 50 A at 50/60 Hz.