4N31SD

Overview

The onsemi 4N31SD is a single-channel optoisolator featuring a Darlington transistor output with a base terminal. It provides high isolation voltage of 5300Vrms and supports DC input. The device operates within a temperature range of -55°C to 100°C, with a maximum forward current of 80mA and a minimum current transfer ratio of 50% at 10mA.

Feature Summary

• High isolation voltage capability for safety-critical applications
• Darlington output configuration with accessible base terminal
• Wide operating temperature range suitable for harsh environments

Applications

• Industrial control systems requiring galvanic isolation
• Power supply feedback loops
• Signal transmission across isolated grounds

Procurement Notes

Verify component status as the 4N31 series may be obsolete. Confirm availability through authorized distributors. Check for valid replacement parts such as 4N30M or 4N33M if sourcing new production units is required. Ensure packaging type matches system requirements.

Selection Notes

Select this component when high isolation voltage and Darlington output gain are necessary. Consider the base terminal feature for improved switching speed or sensitivity adjustments. Verify thermal management capabilities given the operating temperature limits and power dissipation characteristics.

Part Context

The 4N31SD belongs to the 4N31 family of optoisolators from onsemi. It is part of a broader line including variants like 4N31 and 4N32. These devices are designed for general-purpose isolation in digital and analog circuits.

Replacement Considerations

Public confirmed substitutes include 4N30M and 4N33M. Verify pinout compatibility and electrical specifications before substitution.