EL3H4(A)-G

Overview

The EL3H4(A)-G is a single-channel transistor output optocoupler manufactured by Everlight Electronics. It features an infrared emitting diode optically coupled to an NPN phototransistor, encapsulated in a green compound for enhanced isolation. The device provides a high isolation voltage of 3750 Vrms and supports a maximum collector-emitter voltage of 80V. Key electrical parameters include a forward current of up to 50 mA, a typical rise time of 6 µs, and a fall time of 8 µs. It operates within a temperature range of -55°C to 100°C and is available in surface-mount packages such as SSOP-4.

Feature Summary

• High isolation voltage capability of 3750 Vrms for reliable signal transmission across isolated circuits
• Integrated inverse parallel infrared LED configuration for AC and DC input compatibility
• NPN phototransistor output designed for general-purpose switching applications
• Wide operating temperature range suitable for demanding industrial environments

Applications

• General-purpose signal isolation in digital communication interfaces
• Switching power supply feedback loops for voltage regulation
• Microcontroller input/output isolation for noise immunity
• Industrial control systems requiring galvanic separation

Procurement Notes

Verify the specific suffix designation (e.g., TA, TB, VG) against the required package type and reel specifications, as these affect physical dimensions and handling. Confirm RoHS compliance status and moisture sensitivity level requirements prior to ordering. Ensure the selected variant matches the intended PCB footprint and reflow soldering profile constraints defined in the official datasheet.

Selection Notes

Select this component when a single-channel transistor output with high isolation voltage is required. Consider the 3750 Vrms rating for safety-critical applications. Evaluate the 6 µs/8 µs switching speeds against system timing requirements. Verify that the 50 mA forward current limit aligns with the driving circuit capabilities and that the 80V output voltage rating exceeds the load requirements.

Part Context

The EL3H4 series belongs to Everlight's family of transistor output optocouplers. These devices are designed for cost-effective isolation solutions where moderate speed and high voltage isolation are prioritized. The series typically includes variants with different packaging options and regulatory approvals, catering to diverse global market standards and assembly requirements.

Replacement Considerations

Direct replacements may include other single-channel transistor optocouplers with similar 3750 Vrms isolation and SSOP-4 packaging. Verify pinout compatibility and electrical parameter equivalence, particularly CTR ranges and switching times, before substituting.