EL817(C)

Overview

The EL817(C) is a single-channel transistor output optocoupler manufactured by Everlight Electronics Co Ltd. It consists of an infrared emitting diode optically coupled to an NPN phototransistor detector, housed in a 4-pin DIP package. The device provides high isolation voltage of 5000 Vrms between input and output. Key electrical parameters include a collector-emitter breakdown voltage of 35 V, maximum collector current of 50 mA, and forward voltage of 1.4 V at 20 mA. The current transfer ratio ranges from 200% to 400%. Operating temperature spans from -55°C to +110°C.

Feature Summary

• High isolation voltage capability of 5000 Vrms for safe signal transmission across isolated circuits
• Compact 4-pin DIP package design suitable for through-hole mounting applications
• UL recognized with multiple international safety approvals including VDE and SEMKO

Applications

• Industrial control systems requiring galvanic isolation
• Signal transmission between isolated logic circuits
• Power supply feedback loops for voltage regulation

Procurement Notes

Verify the specific suffix designation when ordering, as variations such as (TU) indicate tape and reel packaging while standard versions may come in tubes. Confirm RoHS compliance status and lead times directly with authorized distributors or the manufacturer, as availability varies by region and production batch. Ensure the selected variant matches the required package type and quantity format for your assembly process.

Selection Notes

Select this component when a cost-effective, general-purpose optocoupler with moderate speed and high isolation is required. The EL817(C) offers a balance of performance and reliability for basic digital isolation tasks. Consider the CTR range and operating temperature limits to ensure compatibility with the target circuit environment and signal integrity requirements.

Part Context

The EL817 series is a widely used family of phototransistor output optocouplers known for their versatility in industrial and consumer electronics. The EL817(C) specifically denotes a version within this series with defined current transfer ratio characteristics. It serves as a common replacement for other generic 4-pin DIP optocouplers in legacy designs and new developments requiring simple transistor output isolation.

Replacement Considerations

Direct replacements include other 4-pin DIP transistor output optocouplers with similar pinout and electrical specifications. Verify that substitute components meet the same isolation voltage and CTR requirements. Cross-reference datasheets for pin configuration and thermal characteristics to ensure mechanical and electrical compatibility.