2N6449 JFET — Specifications & Equivalents

About the 2N6449

The 2N6449 is an N-channel JFET with a drain–source voltage (V_DS) rating of 300 V and a continuous drain current (I_D) of 0.01 A. It can dissipate up to 0.8 W and is rated to a junction temperature of 200 °C. It is supplied in the TO-39 package.

At a glance

• Type: N-channel JFET
• Max drain–source voltage (V_DS): 300 V
• Max continuous drain current (I_D): 0.01 A
• Power dissipation (P_D): 0.8 W
• Max junction temperature (T_J): 200 °C
• Package: TO-39
• Manufacturer: Multi-source (JEDEC registered part number)

Typical applications

With its 300 V drain–source rating the 2N6449 sits in the medium-high-voltage class of switching MOSFETs, typically found in telecom and industrial DC rails, boost and flyback converters, LED and backlight drivers and power-factor-correction stages. Common where the bus sits well above 100 V but below rectified mains.

At 0.01 A it is aimed at small-signal and light-load switching rather than power conversion.

Choosing a replacement for the 2N6449

A drop-in substitute for the 2N6449 must be the same N-channel type and offer a drain–source rating of at least 300 V and a continuous drain current rating of at least 0.01 A.

Mechanically, check the replacement against the TO-39 footprint and confirm the pin order — parts sharing a package outline do not always share a pinout.

Because 2N6449 is a JEDEC-registered part number rather than one vendor's proprietary series, it is produced by several manufacturers. Datasheet figures vary slightly between them, so check the datasheet of the brand you actually buy — this also makes like-for-like sourcing easier.

Where the application switches inductive loads or runs near the voltage limit, keep extra headroom rather than choosing a part that only just meets the original numbers.

Frequently asked questions

What is the 2N6449?

The 2N6449 is an N-channel junction field-effect transistor (JFET). It is rated for 300 V drain-source and 0.01 A continuous drain current.

What is the maximum voltage of the 2N6449?

The 2N6449 has a maximum drain-source voltage (Vds) of 300 V. Treat this as an absolute maximum and design with margin, especially when switching inductive loads.

How much current can the 2N6449 handle?

It is rated for 0.01 A of continuous drain current, with power dissipation limited to 0.8 W. Real-world capability depends on your heatsinking and ambient temperature.

What package does the 2N6449 come in?

It is listed in TO-39. Verify the pinout of the specific variant, as one outline can carry different pin assignments.

What can I use to replace the 2N6449?

No verified equivalents are listed yet. Choose a part of the same polarity that meets or exceeds every rating above and shares a compatible package and pinout.