4N33

Overview

The onsemi 4N33 is a single-channel, transistor-output photodarlington optocoupler housed in a PDIP-6 package. It features a DC input configuration with an isolation voltage of 5300 Vrms. Key electrical parameters include a maximum collector-emitter voltage of 30 V, a maximum collector current of 150 mA, and a forward current of 80 mA. The device operates within a temperature range of -55°C to +100°C and has a power dissipation rating of 250 mW.

Feature Summary

• Provides high-voltage electrical isolation between input and output circuits using a photodarlington output structure.

Applications

• General-purpose signal isolation in industrial control systems
• Microprocessor system interface circuits
• Switching power supply feedback loops

Procurement Notes

Verify component status as the 4N33 is listed as obsolete by onsemi. Confirm availability through authorized distributors or secondary markets. Ensure replacement parts meet original specifications for isolation voltage and pin compatibility before integration into existing designs.

Selection Notes

Select this component for applications requiring robust galvanic isolation with moderate speed requirements. Consider the PDIP-6 package for through-hole mounting. Evaluate thermal constraints given the 250 mW power dissipation limit. Verify that the 30 V collector-emitter voltage meets circuit load requirements.

Part Context

The 4N33 belongs to the general-purpose photodarlington optocoupler family from onsemi. It serves as a legacy component for basic isolation tasks. The series includes variants like the 4N33M and surface-mount versions such as the 4N33SM, offering different insulation ratings and packaging options for diverse design needs.

Replacement Considerations

The 4N33M is a confirmed substitute part number from onsemi. Verify if the 4N33M's 4170 Vrms isolation voltage suffices for your application, as it differs from the 4N33's 5300 Vrms rating. Surface-mount alternatives like the 4N33SM require PCB layout adjustments.