Fairchild Semiconductor · Electronic Components
MMBF4391
JFET SWITCH N-CHAN SOT-23
Part NumberMMBF4391
ManufacturerFairchild Semiconductor
AvailabilityAvailable to order — request a quote
Specifications
NSN5961-01-349-0228 (NSN)
Federal Item NameTRANSISTOR
MaterialPLASTIC ENCLOSURE
Current Rating50.00 MILLIAMPERES NOMINAL ZERO-GATE-VOLTAGE DRAIN CURRENT
Terminals3 TAB, SOLDER LUG
Mounting MethodTERMINAL
Overall Length0.125 INCHES NOMINAL
Overall Width0.062 INCHES NOMINAL
Overall Height0.060 INCHES NOMINAL
Internal ConfigurationFIELD EFFECT
Semiconductor MaterialSILICON
Power Rating Per Characteristic350.0 MILLIWATTS MAXIMUM TOTAL POWER DISSIPATION
Federal Supply Class5961 — Semiconductor Devices And Associated Hardware
RH Electronics, Inc. — independent stocking distributor since 1982.
Every shipment inspected on receipt · ISO 9001:2015 · ANSI/ESD S20.20 · ERAI member since 1998 · GIDEP participant
Every shipment inspected on receipt · ISO 9001:2015 · ANSI/ESD S20.20 · ERAI member since 1998 · GIDEP participant
Frequently asked
Is MMBF4391 available?
We can source MMBF4391 even if it isn't in our active stock list. As an independent distributor we reach inventory outside the franchise channel — including hard-to-find and obsolete parts. Send us a quote request.
Is MMBF4391 by Fairchild Semiconductor obsolete or end-of-life?
We specialize in obsolete, end-of-life, and discontinued components. If MMBF4391 has been discontinued, we can often source remaining stock or qualified alternates. Contact us with your quantity and target date.
How does RH Electronics verify parts like MMBF4391?
Every incoming shipment is inspected under our ISO 9001:2015 quality system — documentation, markings, and construction checked against known-good references. For deeper analysis, we direct work through accredited independent labs. We've been an ERAI member since 1998 and a GIDEP participant.
Can you find a cross-reference or alternate for MMBF4391?
Yes. Our team reads part numbers the way they were designed — decoding family, speed, temperature grade, package, and reliability level — to identify acceptable alternates when the exact part isn't available. Submit a quote request and we'll advise.