2N4338-2

Jfets Overview

The Vishay Siliconix 2N4338-2 is an N-channel Junction Field-Effect Transistor (JFET) housed in a hermetically sealed TO-206AA (TO-18) metal can package. It features a Gate-Source Cutoff Voltage (VGS(off)) ranging from -0.3 V to -1 V and a minimum Gate-Source Breakdown Voltage of -50 V. The device exhibits a typical forward transconductance (gfs) of 0.6 mS and a maximum saturation drain current (IDSS) of 0.6 mA at VDS = 15 V. Designed for low-noise applications, it offers an equivalent input noise voltage of 6 nV/√Hz at 1 kHz.

Jfets Feature Summary

• Hermetically sealed TO-206AA (TO-18) metal can construction suitable for military processing
• Low cutoff voltage design accommodating low-level power supplies down to 1 V
• Very low noise characteristics with high-quality low-level signal amplification capabilities
• High input impedance ensuring minimal system error and low signal loss

Jfets Applications

• High-gain, low-noise amplifiers
• Low-current, low-voltage battery-powered amplifiers
• Infrared detector amplifiers
• Ultrahigh input impedance pre-amplifiers

Jfets Procurement Notes

Verify the specific suffix designation against the manufacturer's documentation to confirm exact electrical binning and testing criteria. Ensure the procurement channel provides original manufacturer packaging or certified equivalents to maintain the integrity of the hermetic seal and military-grade specifications associated with this component series.

Jfets Selection Notes

Select the 2N4338 variant when the application requires the lowest possible gate-source cutoff voltage within the specified range. This part is optimal for circuits demanding operation from very low voltage sources while maintaining high input impedance. Consider the thermal derating requirements if operating junction temperatures exceed standard ambient conditions.

Jfets Part Context

This component belongs to the 2N4338/4339/4340/4341 family of N-channel JFETs designed by Vishay Siliconix. While other members of the series offer higher cutoff voltages and currents, the 2N4338 is specifically characterized for its ultra-low pinch-off voltage. It shares the same physical package and basic breakdown ratings as its siblings but differs in static transfer characteristics.

Jfets Replacement Considerations

Direct replacements include the 2N4339, 2N4340, and 2N4341, though these possess progressively higher cutoff voltages and currents. For surface-mount needs, the J/SST201 series offers similar performance in TO-226AA (TO-92) and TO-236 (SOT-23) packages.

Jfets FAQ

What is the maximum allowable gate-source voltage for the 2N4338?

The absolute maximum rating for both Gate-Source and Gate-Drain voltage is -50 V.

Does the 2N4338 support military processing standards?

Yes, the TO-206AA (TO-18) package is hermetically sealed and explicitly stated as suitable for military processing.

What is the typical input capacitance of this JFET?

The common-source input capacitance (Ciss) is typically 5 pF and has a maximum of 7 pF at VDS = 15 V and f = 1 MHz.