SFH618A-4

Overview

The SFH618A-4 is a single-channel optocoupler featuring an infrared LED and NPN silicon phototransistor in a surface mount PDIP package. It offers 5 kVrms isolation voltage, 50 mA collector current, and a minimum current transfer ratio of 32% at 0.5 mA input. The device provides high BVCEO of 55 V and low input current requirements of 0.5 mA.

Feature Summary

• Low input current operation for efficient drive
• High isolation voltage capability
• High current transfer ratios
• Space-efficient dual in line plastic packaging

Applications

• Computer terminals
• Industrial systems controllers
• Measuring instruments
• Signal transmission between systems of different potentials and impedances

Procurement Notes

Verify the specific suffix (e.g., -G, -X, SMT&R) against the datasheet to confirm package type and reel specifications. Ensure compliance with RoHS and UL recognition file E91231 if required by design. Confirm lead spread dimensions match PCB footprint requirements before ordering.

Selection Notes

Select this component when low input current and high CTR are critical for signal integrity. The 55 V BVCEO supports higher voltage switching applications compared to standard variants. Verify isolation voltage ratings meet safety standards for the target application environment.

Part Context

Part of the SFH618A series including SFH618A-2 and SFH618A-3 variants. These isolators share similar electrical characteristics but differ in package options such as DIP or surface mount configurations. The series is designed for general-purpose digital signal isolation in compact designs.

Replacement Considerations

SFH610A-1 is a comparable industry-standard transistor output optocoupler. Verify pinout compatibility and electrical parameter margins before substitution.