EL357NB-G

Overview

The EL357NB-G is a single-channel transistor output optocoupler manufactured by Everlight Electronics. It integrates an infrared emitting diode and an NPN phototransistor detector within a compact 4-pin SOP package with a 2mm body thickness. The device provides high electrical isolation between input and output circuits, rated at 3750 Vrms. Key electrical parameters include a forward voltage of 1.2V typical, a collector-emitter saturation voltage of 100mV at specified currents, and a wide current transfer ratio range of 50% to 600% measured at IF=5mA and VCE=5V. The component supports a maximum forward current of 50mA and operates within a temperature range of -55°C to +110°C.

Feature Summary

• Provides high-voltage electrical isolation between input and output circuits using optical coupling technology.
• Features a compact 4-pin surface mount package designed for dense PCB layouts.
• Offers a wide current transfer ratio range to accommodate various gain requirements in signal transmission.
• Ensures stable operation across a broad industrial temperature range.

Applications

• Industrial control systems requiring signal isolation
• Communication equipment interface circuits
• Power supply feedback loops
• Measurement instruments

Procurement Notes

Verify the specific suffix designation against the manufacturer's official datasheet to confirm pinout configuration and packaging type. Ensure that the selected variant meets the required isolation voltage standards for the target application. Confirm RoHS compliance status if environmental regulations apply. Cross-reference the part number with authorized distributors to ensure authenticity and traceability.

Selection Notes

Select this component when a single-channel isolation solution with high current transfer ratio is required. Consider the 3750 Vrms isolation rating for safety-critical applications. Evaluate the SOP-4 footprint constraints against available board space. Verify that the NPN phototransistor output type aligns with the downstream circuit logic requirements.

Part Context

The EL357NB-G belongs to the EL357N-G series of transistor output optocouplers from Everlight Electronics. This series is engineered for general-purpose signal isolation in compact electronic designs. The family shares common internal architecture but varies in packaging and certification options. The product line emphasizes reliability and compliance with international safety standards.

Replacement Considerations

Consult official substitution lists for compatible alternatives. Verify pin compatibility and electrical parameter equivalence before replacing. Check for updated lifecycle status as some variants may be obsolete.

FAQ

What is the isolation voltage rating of the EL357NB-G?

The device supports an isolation voltage of 3750 Vrms between the input LED and output phototransistor.

What is the typical current transfer ratio range?

The current transfer ratio ranges from 50% to 600% when measured at a forward current of 5mA and collector-emitter voltage of 5V.