SMP4117A

Overview

The InterFET SMP4117A is an N-channel JFET in a surface-mount SOT23 package, designed for ultra-high input impedance applications. It features a gate-to-source breakdown voltage (V(BR)GSS) of -40V and a typical gate leakage current (IGSS) of 1pA at VGS=-20V. The device exhibits a gate-to-source cutoff voltage (VGS(OFF)) ranging from -0.6V to -1.8V and a drain-to-source saturation current (IDSS) between 0.03mA and 0.09mA. Forward transconductance (GFS) spans 70μS to 210μS, with an input capacitance (Ciss) of 3pF. Continuous power dissipation is rated at 350mW.

Feature Summary

• Utilizes proprietary InterFET N0001H geometry for exceptionally high radiation tolerance
• Provides ultra-low gate leakage currents suitable for femtoampere-level signal processing
• Features low input capacitance to minimize circuit loading in high-frequency designs
• Supports edge-case SPICE modeling via InterFET's specific simulation parameters

Applications

• High-impedance buffers and signal mixers
• Military radar and satellite communication systems
• Medical imaging systems and ultrasound monitors

Procurement Notes

Verify the specific suffix 'A' indicates the A-variant electrical characteristics, particularly regarding the tighter bounds on VGS(OFF) and IDSS compared to standard versions. Confirm that the SOT23 bulk or tape-and-reel packaging meets your assembly requirements. Ensure compatibility with InterFET's custom binning options if precise parameter matching is required for your design.

Selection Notes

Select this component when designing circuits requiring minimal input bias current and high radiation hardness. The SOT23 package offers a compact footprint for space-constrained PCB layouts. Consider the SMP4117A over through-hole variants like the 2N4117A when automated surface-mount assembly is preferred. Evaluate the trade-off between the -40V breakdown rating and your circuit's maximum operating voltages.

Part Context

This part belongs to the InterFET 2N4117/A, 2N4118/A, and 2N4119/A family of N-channel JFETs. These devices are engineered for mid-to-high frequency designs where input impedance is critical. The SMP4117A specifically denotes the surface-mount SOT23 version of the 2N4117A, maintaining identical electrical performance while adapting to modern PCB manufacturing processes.

Replacement Considerations

Publicly confirmed cross-reference parts include SST4117, MMBF4117, and VCR7N. Verify pinout compatibility and electrical parameter overlaps before substitution. Note that while these parts are listed as industry standard crosses, specific thermal or radiation tolerances may differ.