IF140AST3TR

Overview

The IF140AST3TR is an N-Channel Junction Field-Effect Transistor (JFET) manufactured by InterFET, utilizing the proprietary N0014L geometry. It is housed in a surface-mount SOT-23 package and supplied on a tape and reel. Key electrical characteristics include a gate-to-source breakdown voltage of -20V, a typical gate leakage current of 100fA at 10V, and an input capacitance of 3pF. The device exhibits a typical noise voltage of 3.0 nV/√Hz, a forward transconductance of 3.8mS, and a cutoff voltage of -3.0V. The drain-to-source saturation current ranges from 5mA to 15mA, with a maximum operating junction temperature of 150°C.

Feature Summary

• Features extremely low gate leakage current, typically 100fA at room temperature, suitable for high-impedance circuits.
• Designed for low-noise applications with a typical input noise voltage of 3.0 nV/√Hz.
• Offers high radiation tolerance for use in demanding environments.
• Compliant with RoHS, REACH, and Chemical Material Reporting standards.

Applications

• Medical imaging systems and ultrasound equipment
• Radar and satellite communications
• Hydrophone preamplifiers
• Low-noise audio filters and headphone amplifiers

Procurement Notes

Verify the specific suffix 'TR' indicates tape and reel packaging when ordering. Confirm that the 'A' designation corresponds to the IF140A variant specifications rather than the standard IF140. Ensure compatibility with SOT-23 land patterns and check for any custom binning requirements if specific parameter tightness is needed for the application.

Selection Notes

Select this component for designs requiring minimal gate leakage and low noise figures at higher frequencies. Compare the -20V breakdown rating against circuit voltage peaks. Consider the SOT-23 thermal derating limits if operating near the maximum junction temperature. Verify that the 3.8mS transconductance meets the gain requirements of the target amplifier stage.

Part Context

This part belongs to the IF140 family of N-Channel JFETs. It serves as a surface-mount alternative to through-hole variants like the TO-72 package. The product line targets military, aerospace, and medical sectors where reliability and low noise are critical. It is positioned as a low-leakage mid-gain solution within InterFET's portfolio.

Replacement Considerations

Official industry standard cross-references include BF512, SST4416, MMBF4416, MMBF5485, and SSTJ211. Similar parts listed by the manufacturer include IFBF512, 2N4416, J304, 2N4303, and SMPJ211. Verify pinout compatibility and electrical parameter overlaps before substitution.

FAQ

Are the source and drain pins interchangeable?

Yes, the datasheet notes that the Source and Drain (S/D) pins are interchangeable.

What is the typical gate leakage current?

The typical gate leakage current is 100fA at 10V.

Does this component support SPICE modeling?

Yes, InterFET provides edge case SPICE modeling for this device.