SMPJ177

Overview

The SMPJ177 is a P-channel Junction Field-Effect Transistor (JFET) manufactured by InterFET, designed for high-gain switching and low-noise applications. It features a typical gate leakage current of 2.5pA at 10V and a saturation current (IDSS) of 10mA. The device exhibits a gate-to-source breakdown voltage (BVGSS) of 55V and an ON resistance (RDS(ON)) ranging from 250 to 300 Ohms. Operating within a junction temperature range of -55°C to 150°C, it supports continuous power dissipation up to 350mW in the SOT-23 package.

Feature Summary

• Proprietary InterFET geometry provides exceptionally high radiation tolerance suitable for demanding environments.
• Ultra-low gate leakage current typically less than 3pA at room temperature ensures minimal signal distortion.
• Low noise profile with a typical value of 2.0 nV/√Hz optimizes performance in sensitive analog circuits.
• High transconductance gain of 10mS typical facilitates efficient amplification and switching operations.

Applications

• Chopper stabilized amplifiers
• Sample and hold circuits
• Medical imaging systems
• Hydrophone preamplifiers
• Electret microphone interfaces

Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to confirm the exact packaging configuration, such as bulk or tape and reel quantities. Confirm RoHS compliance status and ensure the selected variant matches the required thermal and electrical specifications for the target application environment before finalizing procurement.

Selection Notes

Select the SMPJ177 when extremely low gate leakage and high radiation hardness are critical requirements. Compare its cutoff voltage characteristics against the J176 variant to determine suitability for specific low-level power supply control needs. Ensure the chosen package style aligns with the available board space and thermal management capabilities of the design.

Part Context

This component belongs to the InterFET J176/J177 family of P-channel JFETs. These devices share similar core electrical characteristics but differ in cutoff voltage thresholds. The SMPJ177 specifically denotes the surface-mount SOT-23 version, offering interchangeability with industry standard parts like the SST177 and 2N5116 for direct replacement in existing designs.

Replacement Considerations

Public confirmed substitutes include SST177, 2N5116, SST270, and SST271. Verify pinout compatibility and electrical parameter margins before implementation.

FAQ

Are the source and drain pins interchangeable on the SMPJ177?

Yes, the datasheet specifies that the Source and Drain (S/D) pins are interchangeable for both the SOT-23 and TO-92 packages.

What is the maximum operating junction temperature for this device?

The maximum operating junction temperature is 150°C, with a minimum storage and operating temperature of -55°C.

How does the SMPJ177 differ from the J176 regarding cutoff voltage?

The SMPJ177 has a lower gate-to-source cutoff voltage (maximum 2.25V) compared to the J176 (maximum 4V), making it ideal for low-level power supplies.