FOD4108S

Triac, SCR Output Optoisolators Overview

The FOD4108S is a surface-mount optocoupler featuring a triac output with an integrated zero-crossing detection circuit. It provides electrical isolation between control and power stages, rated at 5000 Vrms isolation voltage. The device supports an on-state current of 300 mA and offers a high off-state blocking voltage of 800 V. Key performance metrics include a minimum static dv/dt rating of 10 kV/µs to prevent false triggering and a maximum LED trigger current of 2 mA. It is housed in a compact 6-SMD package.

Triac, SCR Output Optoisolators Feature Summary

• Integrated zero-voltage crossing detection for reduced electromagnetic interference and switch-on transients
• High common-mode transient immunity with a static dv/dt rating of 10 kV/µs
• High trigger sensitivity allowing operation with low input LED currents
• Robust insulation capability suitable for mains-connected applications

Triac, SCR Output Optoisolators Applications

• Solid-state relay driver circuits
• AC motor speed control systems
• Lighting dimmer applications
• General AC power switching interfaces

Triac, SCR Output Optoisolators Procurement Notes

Verify the specific suffix against the manufacturer's official documentation to confirm pinout configuration and package dimensions, as variations may exist within the series. Ensure the component status is listed as active in current catalogs to guarantee supply availability. Cross-reference the datasheet revision date to confirm compliance with current safety standards and isolation ratings required for the target application design.

Triac, SCR Output Optoisolators Selection Notes

Select this component when zero-crossing switching is required to minimize noise and stress on AC loads. The 800 V blocking voltage is suitable for standard single-phase mains voltages. Consider the 300 mA RMS current limit when sizing for load requirements. The surface-mount package is appropriate for automated assembly processes where space constraints are critical compared to through-hole alternatives.

Triac, SCR Output Optoisolators Part Context

This device belongs to the family of triac output optocouplers designed for isolating low-voltage control logic from high-voltage AC power lines. Unlike simple phototriacs, the inclusion of internal circuitry for zero-crossing detection distinguishes it from basic switching components. It serves as a bridge between microcontroller outputs and AC load management, ensuring safe galvanic separation while providing precise timing control for power delivery.

Triac, SCR Output Optoisolators Replacement Considerations

Consult the manufacturer's substitution guide for direct replacements. Generic equivalents may lack the specific zero-crossing threshold or dv/dt immunity characteristics documented for this part number.