MMBTA28-7-F Diodes Inc. Transistor BJT NPN (SOT23 (3-Pin)) In Stock

Diodes Inc. MMBTA28-7-F is an NPN Darlington transistor in a SOT-23 3-pin package with 80 V collector-emitter voltage, 0.5 A maximum collector current, and minimum DC current gain (hFE) of 10000. Designed for high-gain switching and amplification in compact SMT circuits. RoHS compliant with worldwide shipping available.

ACTIVETransistor BJT NPNVerified Jun 2026
Package / Visual Reference
MMBTA28-7-FSOT23 (3-Pin)
Quick Facts
Manufacturer
Diodes Inc.
Package
SOT23 (3-Pin)
Pin Count
3
Lifecycle
ACTIVE
Category
Transistor BJT NPN
Price
From $0.0323(MOQ 50)
Temp Range
?°C to 150.0°C
RoHS
Compliant
Lead Time
3–7 business days
Shipping
DHL Express · Worldwide

Key Features

  • Darlington NPN configuration with minimum hFE of 10000 enables microcontroller logic signals to drive loads up to 0.5 A without additional amplification stages
  • 80 V collector-emitter breakdown voltage supports switching applications in industrial and automotive-adjacent circuits above standard 5 V logic rails
  • Compact SOT-23 (3-pin) SMD package occupies minimal PCB area for portable and space-constrained switching circuit designs

Applications

The MMBTA28-7-F is ideal for high-gain switch applications where a single transistor must drive relay coils, solenoids, or LED arrays directly from a low-current microcontroller GPIO pin. Its Darlington configuration with hFE ≥ 10000 means that even a 5 µA base current can switch up to 50 mA collector loads, making it suitable for optocoupler output stages, motor control pre-drivers, and sensor interface amplifiers. The SOT-23 package enables high-density placement in portable instrumentation, consumer electronics, and IoT gateway boards.

Specifications

Pbfree CodeYes
Factory Lead Time12Weeks
YTEOL7
Collector Current-Max (IC)0.5A
Collector-Emitter Voltage-Max80V
ConfigurationDARLINGTON
DC Current Gain-Min (hFE)10000
JESD-30 CodeR-PDSO-G3
JESD-609 Codee3
Number of Elements1
Package Body MaterialPLASTIC/EPOXY
Package ShapeRECTANGULAR
Package StyleSMALL OUTLINE
Peak Reflow Temperature (Cel)255
Polarity/Channel TypeNPN
Power Dissipation-Max (Abs)0.3W
Qualification StatusNot Qualified
Surface MountYES
Terminal FinishMatte Tin (Sn)
Terminal FormGULL WING
Terminal PositionDUAL
Time@Peak Reflow Temperature-Max (s)30
Transistor ApplicationSWITCHING
Transistor Element MaterialSILICON
Transition Frequency-Nom (fT)125MHz
PackageSOT23 (3-Pin)

Compliance & Regulatory

RoHS StatusCompliant
Lead-FreeYes (Pb-Free)
Moisture Sensitivity LevelMSL 1
ECCNEAR99
Country of OriginMainland China

Datasheet

MMBTA28-7-F Datasheet Download

Official datasheet from Diodes Inc.

Alternate & Equivalent Parts

No known alternates. Submit an RFQ and our team can suggest alternatives.

Frequently Asked Questions

What base current is needed to saturate the MMBTA28-7-F when driving a 100 mA relay coil?

With a minimum hFE of 10000 in Darlington configuration, the MMBTA28-7-F requires only 10 µA of base current to switch 100 mA at the collector. A typical 3.3 V GPIO output through a 100 kΩ series resistor will provide approximately 33 µA base drive — more than enough to fully saturate the transistor and drive the relay coil with ample margin.

What is the maximum collector-emitter voltage for the MMBTA28-7-F, and does it support 48 V industrial loads?

The MMBTA28-7-F has an 80 V maximum collector-emitter voltage (VCEO), providing substantial margin above 48 V industrial power rails. This headroom accounts for inductive kickback spikes from relay coils or solenoids, which can transiently exceed the supply voltage. A flyback diode across the load is still recommended, but the 80 V rating ensures the transistor survives typical 48 V switching transients without breakdown.

How does the MMBTA28-7-F Darlington transistor compare to a single-stage NPN for microcontroller-driven switching?

A single-stage NPN transistor typically has hFE between 100 and 300, requiring 0.3 to 1 mA base drive for a 100 mA load. The MMBTA28-7-F Darlington's hFE ≥ 10000 reduces base current requirements to under 10 µA for the same 100 mA load, allowing direct GPIO drive without current buffers. The trade-off is a higher saturation voltage of approximately 1.0 V to 1.2 V (versus 0.2 V for a single-stage NPN), which increases power dissipation slightly at maximum collector current of 0.5 A.

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About Diodes Inc.

Diodes Inc. is a leading electronic component manufacturer. FindMyChip sources Diodes Inc. ICs directly from authorized China distributors, offering competitive pricing and reliable stock.

AvailabilityIn Stock
Reference Price (USD)
From $0.0323
Buy from 1pc · Factory-direct pricing
Qty.Unit PriceExt. Price
50+$0.1700$8.50
100+$0.1012$10.12
500+$0.0743$37.14
1000+$0.0655$65.54
3000+$0.0560$168.00
6000+$0.0323$193.80
pcs
Unit price: $0.1700 · Total: $8.50

In Stock · 24h Response · Worldwide Shipping

Lead Time3-7 business days
MOQFrom 1 piece
ShippingDHL / FedEx / UPS
OriginChina (Authorized)

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