MMBF4392

Overview

The MMBF4392 is an N-channel JFET switch designed for low-level analog applications. It features a Drain-Source On Resistance of 60 Ohms and a Zero-Gate Voltage Drain Current ranging from 25 mA to 75 mA at VDS = 20 V. The device supports a Drain-Gate Voltage of 30 V and a Gate-Source Voltage of -30 V, with a total power dissipation of 350 mW. Input capacitance is specified at 14 pF. Operating temperatures range from -55°C to 150°C.

Feature Summary

• Designed specifically for low-level analog switching and sample-and-hold circuits
• Capable of operation in chopper-stabilized amplifier configurations
• Features interchangeable source and drain terminals within the SOT-23 package

Applications

• Low level analog switching
• Sample and hold circuits
• Chopper stabilized amplifiers

Procurement Notes

Verify the specific part number suffix against current ON Semiconductor documentation, as Fairchild Semiconductor orderable part numbers may have been updated to remove underscores during integration. Confirm that the component meets RoHS3 compliance standards and check for any recent Product Change Notices regarding assembly or sourcing modifications before finalizing procurement.

Selection Notes

Select this component when a depletion mode N-channel JFET is required for signal routing in precision analog environments. The MMBF4392 offers a moderate on-resistance compared to the MMBF4391 and higher cutoff voltage than the MMBF4393. Ensure the application voltage does not exceed the 30 V breakdown rating and verify thermal management capabilities for the 350 mW dissipation limit.

Part Context

This device belongs to the MMBF439xL series of N-Channel Switches manufactured by ON Semiconductor. It is sourced from process 51 and shares functional similarities with the J111 transistor. The product line includes variants MMBF4391 and MMBF4393, which differ primarily in their gate-source cutoff voltage and zero-gate voltage drain current specifications while maintaining the same physical footprint.

Replacement Considerations

• MMBF4391LT1G
• MMBF4393LT1G

FAQ

Are the source and drain terminals interchangeable?

Yes, the datasheet explicitly notes that the source and drain leads are interchangeable.

What is the maximum junction temperature?

The absolute maximum ratings specify a maximum junction temperature of 150°C.

How does the MMBF4392 compare to the MMBF4391?

The MMBF4392 has a lower Zero-Gate Voltage Drain Current (25-75 mA vs 50-150 mA) and a higher Gate-Source Cut-Off Voltage (-2.0 to -5.0 V vs -4.0 to -10.0 V) compared to the MMBF4391.