4N25M

Overview

The Lite-On 4N25M is a single-channel transistor output optocoupler housed in a 6-pin DIP package. It features a DC input with a maximum forward current of 60mA and a typical forward voltage of 1.5V. The device provides an isolation voltage of 2500Vrms, ensuring robust signal transmission between isolated circuits. Key electrical parameters include a minimum current transfer ratio of 20%, a collector-emitter saturation voltage of 500mV, and a power dissipation rating of 250mW. Operating temperatures range from -55°C to +100°C.

Feature Summary

• Provides galvanic isolation for signal transmission between circuits operating at different potentials
• Includes accessible base pin on the phototransistor output for enhanced switching speed control
• Offers high isolation voltage capability to protect sensitive low-voltage components

Applications

• I/O interfaces for computer systems
• Signal transmission in measuring instruments
• Coupling between system appliances and control circuits

Procurement Notes

Verify the manufacturer origin carefully, as the 4N25M part number is used by multiple vendors including onsemi and Lite-On. Confirm that the specific datasheet matches the required isolation voltage (2500Vrms for Lite-On) and package dimensions. Ensure the component is new and not obsolete or end-of-life stock before finalizing procurement decisions.

Selection Notes

Select this component when a standard single-channel optocoupler with accessible transistor base is required for general-purpose isolation. Consider the 2500Vrms isolation rating against environmental noise requirements. Verify that the 60mA input current limit and 30V output voltage rating align with the target circuit design constraints.

Part Context

The 4N25M belongs to the widely recognized 4N25 series of optocouplers, which are industry-standard devices for basic isolation tasks. Lite-On manufactures this variant using a PDIP-6 package, distinguishing it from surface-mount alternatives like the 4N25S. This component serves as a fundamental building block for digital signal isolation in legacy and modern electronic designs.

Replacement Considerations

• Lite-On 4N25S-TA1 (Surface Mount Variant)
• onsemi 4N25M (Different Manufacturer)

FAQ

What is the purpose of the exposed base pin on the phototransistor?

The exposed base pin allows for external biasing or faster discharge of the base-collector capacitance, enabling improved switching speed performance compared to devices without this feature.

What is the maximum isolation voltage for the Lite-On 4N25M?

The Lite-On 4N25M supports an isolation voltage of 2500Vrms, suitable for protecting low-voltage logic circuits from higher voltage domains.