Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

Home > Products > Discrete Semiconductor Products > Transistors > Bipolar (BJT) > Single Bipolar Transistors

Diodes Incorporated MMBT4124-7-F

Name: MMBT4124-7-F
Brand: Diodes Incorporated
SKU: MMBT4124-7-F
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: MMBT4124-7-F

Manufacturer:: Diodes Incorporated

Category:: Single Bipolar Transistors

Package:: TO-236-3, SC-59, SOT-23-3

Datasheet:: MMBT4124-7-F.pdf

Description:: TRANS NPN 25V 0.2A SOT-23-3

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:4,955

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

MMBT4124-7-F from Diodes Incorporated is a 25V NPN small-signal transistor in SOT23 package, rated for 200mA collector current, 310mW power dissipation, and 300MHz transition frequency; it delivers high DC current gain (h_FE = 120–360 at I_C = 2–50mA) and low V_CE(sat) (≤0.30V), enabling use in medium-power switching and amplification circuits in automotive body control modules.

For engineers reviewing the MMBT4124-7-F datasheet, MMBT4124-7-F pinout, MMBT4124-7-F application, or MMBT4124-7-F equivalent, key selection criteria include V_CEO = 25V, I_C = 200mA, h_FE range, AEC-Q101 qualification, and SOT23 thermal performance under pulsed and continuous operation.

Technical Context

This NPN bipolar junction transistor operates with base-emitter forward bias to control collector current flow, supporting both linear amplification (via h_FE and h_fe) and saturated switching (via V_CE(sat) ≤ 0.30V at I_C/I_B = 10). Its f_T = 300MHz enables RF-capable signal amplification up to VHF band.

Designed for AEC-Q101 reliability, it features 4kV HBM ESD rating, -55°C to +150°C operating range, and thermally optimized SOT23 package with R_θJA = 403°C/W on minimal PCB copper-suitable for space-constrained automotive and industrial control nodes requiring stable gain and low saturation loss.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	25 V - Maximum safe collector-emitter voltage before breakdown; defines upper rail limit in switching applications.
I_C	200 mA - Continuous collector current handling capacity; supports medium-power load switching without derating at 25°C.
h_FE	120–360 - DC current gain range across 2–50mA I_C; enables predictable base drive sizing for robust turn-on in logic-level interfaces.
V_CE(sat)	≤0.30 V @ I_C=50mA, I_B=5mA - Low saturation voltage minimizes conduction loss and self-heating in high-duty-cycle switches.
f_T	300 MHz - Transition frequency confirms usable bandwidth for RF amplification and fast digital switching (t_ON/t_OFF < 5ns).
R_θJA	403 °C/W - Junction-to-ambient thermal resistance on minimal FR4 pad; sets max power envelope for ambient-limited designs.
ESD HBM	4,000 V - Human Body Model rating ensures robustness against assembly and handling electrostatic discharge.

Pinout & Package

SOT23 plastic surface-mount package with matte tin-plated leads, UL 94V-0 flammability rating, and 0.008g mass; moisture sensitivity level 1 per J-STD-020.

Pin/Terminal	Circuit Role	Design Meaning
1 (Emitter)	Current sink terminal	Reference node for base drive; connects to ground or low-side return path in common-emitter configurations.
2 (Base)	Control input	Receives current-limited drive (typically 1–10% of I_C) to bias transistor into active or saturation region.
3 (Collector)	Current source terminal	Connects to load and supply rail; carries full switched current with minimal V_CE(sat) drop in on-state.

Key Features

Feature	Design Value
AEC-Q101 qualified	Validated for automotive electronics including body control units and lighting drivers requiring extended temperature and reliability compliance.
Lead-free & halogen-free	Meets RoHS 2 and "Green" standards (<900ppm Br/Cl, <1000ppm Sb); eliminates hazardous substances for end-of-life recycling and manufacturing safety.
High f_T and h_FE	300MHz f_T and 120–360 h_FE support both analog amplification (e.g., sensor signal conditioning) and fast digital switching (e.g., MCU-driven LED drivers).
Low V_CE(sat)	≤0.30V saturation voltage at 50mA reduces power loss by >40% vs. legacy transistors, improving efficiency in battery-powered systems.

Applications

Automotive Interior Lighting Control

Industrial PLC Digital Output Stage

Use Scenario: Driving 12V LED strings in door courtesy lights and map lamps using PWM from microcontroller GPIO.

IC Role / Device Role / Timing Role: NPN switch controlling current path between LED anode and ground; operates in saturation with 5kHz PWM.

Use Value: V_CE(sat) ≤ 0.30V ensures <15mW conduction loss per channel, minimizing thermal rise in sealed lamp housings.

Use Scenario: Isolating and amplifying 24V DC output signals from programmable logic controller CPU to field actuators.

IC Role / Device Role / Timing Role: Medium-power interface transistor translating 3.3V/5V logic levels to 24V load switching capability.

Use Value: 200mA I_C rating and AEC-Q101 qualification ensure reliable operation across industrial temperature cycles and vibration environments.

Consumer Appliance Motor Driver

Medical Diagnostic Sensor Interface

Use Scenario: Switching small brushed DC motors in smart home appliances (e.g., HVAC damper actuators) via MCU outputs.

IC Role / Device Role / Timing Role: Low-side switch enabling bidirectional motor control when paired with complementary PNP (MMBT4126).

Use Value: Complementary pairing simplifies H-bridge design; h_FE stability over -40°C to +85°C maintains consistent drive strength.

Use Scenario: Amplifying weak analog signals from piezoresistive pressure sensors in portable diagnostic devices.

IC Role / Device Role / Timing Role: Small-signal amplifier in non-inverting common-emitter configuration with fixed bias network.

Use Value: 300MHz f_T and 120–360 h_FE support accurate 10kHz sensor bandwidth without phase shift or gain roll-off.

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN small-signal transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
BC847BW,115	V_CEO = 45V, I_C = 100mA, h_FE = 200–450, SOT323 package	Higher voltage rating but lower current; smaller footprint limits thermal margin in sustained 150mA loads.	Select when board space is critical and V_CEO > 30V is required; verify thermal derating at elevated ambient.
PN2222A-AP	V_CEO = 40V, I_C = 800mA, TO-92 package, no AEC-Q101 qualification	Higher current and voltage, but through-hole mounting and lack of automotive qualification limit use in modern compact PCBs.	Choose only for prototyping or non-automotive industrial applications where leaded assembly is acceptable and qualification is not mandated.

Compared with BC847BW and PN2222A-AP, the MMBT4124-7-F uniquely balances AEC-Q101 compliance, 200mA current capability, and SOT23 thermal performance-making it optimal for production automotive and space-constrained industrial switching where reliability and manufacturability are jointly prioritized.

Availability

MMBT4124-7-F is available at Aetrix Electronics and suitable for automotive interior lighting control, industrial PLC digital output stages, and consumer appliance motor driver applications requiring stable component supply and long-term lifecycle continuity.

Supply support for MMBT4124-7-F includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability components for automotive, industrial, and consumer markets.

The MMBT4124 belongs to Diodes' AEC-Q101-qualified small-signal transistor product line, engineered for robust switching and amplification in harsh-environment electronic control units.

FAQ

What is the maximum continuous collector current for MMBT4124-7-F?

The absolute maximum continuous collector current is 200mA at T_A = +25°C. Derating applies above 25°C per the datasheet's thermal curve: power dissipation drops linearly to zero at 150°C ambient, with R_θJA = 403°C/W on standard FR4 layout.

Is MMBT4124-7-F suitable for automotive applications?

Yes-it is fully qualified to AEC-Q101 standards, rated for -55°C to +150°C operation, and features 4kV HBM ESD protection. Its SOT23 package, RoHS/Green compliance, and production traceability make it approved for use in automotive body electronics and lighting control modules.

How does the h_FE vary with collector current?

h_FE ranges from 120 at I_C = 2mA to 360 at I_C = 50mA (V_CE = 1.0V, T_A = 25°C). The datasheet's Figure 1 shows peak gain near 10mA, declining at higher currents due to internal recombination effects-designers should select bias points within 5–50mA for stable gain.

What is the marking code on the top of the SOT23 package?

The device is marked "K1B" on the top surface of the SOT23 case, per Diodes' standard marking scheme. "K1" denotes the MMBT4124 product type, and "B" indicates the date code year (2014); full date decoding requires referencing the month/year table in the datasheet.

MMBT4124-7-F Specifications

Product attributes: Attribute value

Manufacturer:: Diodes Incorporated

Series:: -

Package/Case:: TO-236-3, SC-59, SOT-23-3

Packaging:: Tape & Reel (TR)

Product Status:: Obsolete

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 200 mA

Voltage - Collector Emitter Breakdown (Max):: 25 V

Vce Saturation (Max) @ Ib, Ic:: 300mV @ 5mA, 50mA

Current - Collector Cutoff (Max):: 50nA (ICBO)

DC Current Gain (hFE) (Min) @ Ic, Vce:: 120 @ 2mA, 1V

Power - Max:: 300 mW

Frequency - Transition:: 300MHz

Operating Temperature:: -55°C ~ 150°C (TJ)

Grade:: Automotive

Qualification:: AEC-Q101

Mounting Type:: Surface Mount

Supplier Device Package:: SOT-23-3

MMBT4124-7-F FAQ

1.How can I place an order for MMBT4124-7-F through Aetrix?

Please submit a Request for Quotation (RFQ) for MMBT4124-7-F on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for MMBT4124-7-F reliable?

The price and inventory of MMBT4124-7-F are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MMBT4124-7-F is usually 5 days.

3.What payment methods are accepted for MMBT4124-7-F?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MMBT4124-7-F transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for MMBT4124-7-F?

MMBT4124-7-F orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your MMBT4124-7-F order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for MMBT4124-7-F?

For technical support, including MMBT4124-7-F datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MMBT4124-7-F requirements.

6.How does Aetrix verify that MMBT4124-7-F is sourced from the original manufacturer or authorized distributors?

All MMBT4124-7-F products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that MMBT4124-7-F meets industry standards.

7.What is the process for return or replacement of MMBT4124-7-F?

All MMBT4124-7-F units undergo pre-shipment inspection (PSI). If there is an issue with MMBT4124-7-F, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The MMBT4124-7-F part is unused and in its original packaging.

Return procedure for MMBT4124-7-F:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

Tech Hub

2026-08-21 What Is an LED Driver? Types, Circuits, Dimming, and Selection

An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…

2026-08-18 Operational Amplifier (Op Amp): Basics, Configurations, Feedback and Applications

Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…

2026-08-14 Jumper Cables: How to Use, Connect and Choose Them Safely

Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…

2026-08-11 LDO Regulator: Dropout Voltage, Noise, PSRR and Power Dissipation

LDO regulator guide covering low dropout voltage, power dissipation, thermal design, PSRR, output noise, capacitor stability, adjustable LDO circuits, LDO vs buck converter and datasheet selection chec…

2026-08-06 Conditional Access Module: CAM, CI/CI+ and DVB Security

Conditional Access Module guide covering CAM meaning, CI/CI+ interface, smart card authorization, DVB security workflow, TV and set-top box compatibility, internal electronics, ESD protection, connecto…

2026-08-03 Electronic Component Obsolescence: EOL Risks, Replacement Options and Last-Time Buy Strategy

Guide to electronic component obsolescence covering EOL risk, PCN/PDN notices, last-time buy planning, replacement options, form-fit-function validation, counterfeit risk and BOM lifecycle management.

2026-07-29 18650 Battery: Voltage, Capacity, Charging and Pack Design

18650 battery guide covering lithium-ion cell basics, 3.6V/3.7V voltage, 4.2V charging, mAh and Wh capacity, protected cells, chargers, BMS, series-parallel packs, holders, welding and sourcing checks.…

2026-07-27 Hall Effect Sensor: Working Principle, Types, Circuits and Applications

Hall effect sensor guide covering working principle, linear and digital sensors, Arduino circuits, current sensing, speed detection, automotive applications, A3144 examples, signal filtering and datash…

2026-07-20 Product Change Notification (PCN) in Electronic Components: Meaning and Supply Chain Response

Product Change Notification guide for electronic components, covering PCN meaning, PCN vs PDN/EOL, common change types, risk levels, form-fit-function review, engineering validation, BOM control, LTB/L…

2026-07-19 Blend Door Actuator: Symptoms, Location, Reset and Replacement Guide

A practical guide to blend door actuators, covering HVAC function, symptoms, location, AC and heater issues, reset and calibration, replacement cost, electrical diagnosis, compatibility checks, and rep…