4N28FM

Overview

The onsemi 4N28FM is a single-channel optoisolator featuring a transistor output with an accessible base connection. It provides electrical isolation between input and output circuits, rated for a peak isolation voltage of 7500V. The device operates within a temperature range of -55°C to +100°C and utilizes a 6-SMD Gull Wing surface-mount package.

Feature Summary

• Provides high-voltage electrical isolation between input and output circuits
• Features a phototransistor output with an exposed base terminal for external control
• Designed for surface-mount assembly in compact electronic designs

Applications

• Power supply signal feedback loops
• Microcontroller interface isolation
• General-purpose digital signal transmission

Procurement Notes

Verify component status as the 4N28FM may be classified as obsolete by the manufacturer. Confirm availability through authorized distributors or approved substitute sources. Ensure compliance with RoHS directives and check for specific tape-and-reel packaging requirements if applicable to your production line.

Selection Notes

Select this component when a low-cost, single-channel isolation solution with a base-connected phototransistor is required. Consider the 6-SMD package constraints and operating temperature limits. Evaluate alternative active devices if higher current transfer ratios or faster switching speeds are necessary for the specific application design.

Part Context

This component belongs to the standard 4N28 family of optocouplers, widely used for basic isolation tasks. It serves as a fundamental building block for separating noisy power stages from sensitive logic circuits. The series offers a balance of performance and cost-effectiveness for general industrial and consumer electronics applications.

Replacement Considerations

Public confirmed substitutes include the 4N28SR2VM. Verify pinout compatibility and electrical specifications before integration.