SFH618A-2

Overview

The SFH618A-2 is a single-channel transistor output optocoupler manufactured by Vishay Semiconductor Opto Division. It features an NPN phototransistor output and utilizes a through-hole DIP-4 package. The device provides high isolation with an insulation voltage of 5300 Vrms. Key electrical parameters include a maximum collector-emitter voltage of 55 V, a maximum collector current of 100 mA, and a forward voltage of 1.5 V at a forward current of 60 mA. The current transfer ratio ranges from 63% to 125%. Typical switching times are 3.5 µs for rise time and 5 µs for fall time.

Feature Summary

• Provides galvanic isolation between input and output circuits via an internal LED and phototransistor pair.
• Features a standard four-pin DIP package suitable for through-hole mounting on printed circuit boards.
• Delivers high isolation voltage capability to protect low-voltage control circuits from high-voltage loads.

Applications

• General purpose signal isolation in industrial control systems
• Switching power supply feedback loops
• Microcontroller interface circuits requiring electrical separation

Procurement Notes

Verify the specific suffix designation against official Vishay documentation to confirm the exact Current Transfer Ratio binning and mechanical tolerance specifications. Ensure that the procurement source provides valid RoHS compliance certificates as required for the component series. Cross-reference the manufacturer part number with authorized distributor catalogs to confirm availability and authenticity before finalizing orders.

Selection Notes

Select this component when a through-hole DIP-4 form factor is required for assembly processes. Choose based on the necessary isolation voltage rating and the specific current transfer ratio range needed for the application logic levels. Consider the thermal dissipation capabilities and operating temperature range relative to the intended environmental conditions.

Part Context

This component belongs to the SFH618 family of transistor output optocouplers. Variants within this series differ primarily in their current transfer ratio bins and packaging options, such as surface mount or through-hole configurations. The SFH618A-2 specifically denotes the through-hole version with a defined CTR range of 63% to 125%.

Replacement Considerations

The SFH617A-2 is documented as a recommended alternative with similar characteristics but different switching speeds and voltage ratings. Verify pin compatibility and electrical parameter overlaps before substitution.