EL121N(BC)(TA)-V

Overview

The EL121N(BC)(TA)-V is a phototransistor output optocoupler manufactured by Everlight Electronics. It features a 4-pin SOP-DC package and provides electrical isolation between input and output circuits. Key electrical parameters include a maximum DC forward current of 50 mA, a typical forward voltage of 1.2 V, and a maximum collector-emitter saturation voltage of 200 mV. The device operates within a temperature range of -55°C to 110°C.

Feature Summary

• Photovoltaic or phototransistor output configuration for signal isolation
• Compact 4-pin SOP-DC surface mount packaging
• High operating temperature capability up to 110°C

Applications

• Digital logic interface circuits
• Signal isolation in microprocessor systems
• Memory module interfaces

Procurement Notes

Verify the specific suffix (BC)(TA)-V against the manufacturer's datasheet to confirm tape-and-reel packaging and lead-free status. Ensure the ordering part number matches the required isolation voltage and package variant. Cross-reference with official Everlight documentation to avoid counterfeit components.

Selection Notes

Select this component when a compact, high-temperature rated phototransistor optocoupler is required for digital signal isolation. Consider the 4-pin SOP-DC footprint for space-constrained PCB layouts. Verify that the 50 mA forward current rating meets the LED drive requirements of the application circuit.

Part Context

This part belongs to Everlight's line of transistor output optocouplers designed for general-purpose isolation. The EL121N series typically offers high reliability and compatibility with standard surface mount assembly processes. It serves as a fundamental component for breaking ground loops and protecting sensitive electronics.

Replacement Considerations

Check for direct pin-compatible substitutes from Everlight or other manufacturers offering similar phototransistor outputs in SOP-4 packages. Verify matching isolation voltage ratings and CTR specifications before substitution.