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

Diodes Incorporated MMBT4124-7

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

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Part No.:: MMBT4124-7

Manufacturer:: Diodes Incorporated

Category:: Single Bipolar Transistors

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

Datasheet:: MMBT4124-7.pdf

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

Quantity:: RFQ Add To RFQ list

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Product details

Overview

MMBT4124-7 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 serves as a medium-power amplifier or switch in biasing, signal conditioning, and load-driving circuits within automotive control modules and industrial sensor interfaces.

For engineers reviewing the MMBT4124-7 datasheet, MMBT4124-7 pinout, MMBT4124-7 application, or MMBT4124-7 equivalent, key selection criteria include V_CEO = 25V, h_FE = 120–360 at I_C = 2mA, V_CE(sat) ≤ 0.30V at I_C = 50mA/I_B = 5mA, f_T = 300MHz, and AEC-Q101 qualification for automotive-grade reliability.

Technical Context

This NPN bipolar junction transistor operates with a minimum DC current gain of 120 at 2mA and up to 360 at low current, supporting stable linear amplification and saturated switching. Its 300MHz f_T enables use in audio-frequency amplifiers and digital logic interface stages up to ~10MHz.

The device features 5V V_EBO, 30V V_CBO, and 4.0pF C_obo at 5V, making it suitable for low-voltage, moderate-speed switching where base drive efficiency and output capacitance impact rise/fall time.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	25V - Maximum safe collector-emitter voltage before breakdown under open-base conditions.
I_C	200mA - Continuous collector current limit defining maximum load drive capability.
h_FE	120–360 - DC current gain range enabling predictable base current sizing for bias networks.
V_CE(sat)	≤0.30V @ 50mA/5mA - Low saturation voltage minimizes conduction loss in switching applications.
f_T	300MHz - Transition frequency indicating usable bandwidth for small-signal amplification.
P_D	310mW - Power dissipation limit on standard FR4 PCB, defining thermal derating envelope.
ESD HBM	4000V - Robustness against human-body electrostatic discharge during handling and assembly.

Pinout & Package

SOT23 surface-mount package: 3-pin, 2.4mm × 1.3mm footprint, 0.9mm height, matte tin-plated leads, JEDEC-standard lead finish, moisture sensitivity level 1.

Pin/Terminal	Circuit Role	Design Meaning
1 (Emitter)	Current sink terminal	Reference node for base-emitter bias; connects to ground or low-side return path.
2 (Base)	Control input	Receives current-limited drive to modulate collector current; requires series resistor for digital logic interfacing.
3 (Collector)	Current source terminal	Delivers switched or amplified current to load; routed to V_CC or active pull-up network.

Key Features

Feature	Design Value
AEC-Q101 qualified	Validated for automotive electronics per stress-test requirements including temperature cycling and HTRB.
Lead-free & halogen-free	Complies with RoHS 2 and "Green" definition (<900ppm Br+Cl, <1000ppm Sb), enabling eco-compliant manufacturing.
Low V_CE(sat)	0.30V max at 50mA ensures <15mW conduction loss, improving efficiency in battery-powered switches.
High f_T	300MHz supports stable gain in audio preamps and fast edge response in pulse-width modulation drivers.

Applications

Automotive Door Module

Industrial Sensor Interface

Use Scenario: Driving LED status indicators and relay coils in door control units exposed to -40°C to +125°C ambient.

IC Role / Device Role / Timing Role: NPN switch controlling 100mA loads with <1µs turn-on delay and minimal thermal rise.

Use Value: AEC-Q101 rating ensures long-term reliability; 25V V_CEO accommodates 12V automotive transients.

Use Scenario: Level-shifting and buffering analog sensor outputs (e.g., thermistor, potentiometer) into MCU ADC inputs.

IC Role / Device Role / Timing Role: Emitter-follower buffer providing high input impedance and low output impedance.

Use Value: h_FE ≥120 ensures stable bias across temperature; 5V V_EBO prevents reverse-base damage during signal inversion.

Consumer Audio Amplifier

Power Supply Enable Circuit

Use Scenario: First-stage preamplifier in portable speaker systems operating from single 3.3V or 5V rails.

IC Role / Device Role / Timing Role: Common-emitter small-signal amplifier with 300MHz f_T preserving audio fidelity up to 20kHz.

Use Value: 310mW P_D allows continuous operation at 10mW quiescent power without heatsinking.

Use Scenario: Enabling/disabling secondary DC-DC converter rails via microcontroller GPIO in multi-rail embedded systems.

IC Role / Device Role / Timing Role: High-gain saturated switch turning on/off 150mA enable lines with <100ns propagation delay.

Use Value: V_CE(sat) ≤0.30V limits enable-line voltage drop to <3% of 3.3V rail, ensuring clean startup sequencing.

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
MMBT4401-7-F	V_CEO = 40V, h_FE = 100–300, f_T = 250MHz, same SOT23 package	Higher voltage margin but lower f_T; suited for 24V industrial controls over automotive 12V	Select when >30V transient immunity is required and bandwidth <250MHz suffices.
BC846B,215	V_CEO = 65V, h_FE = 200–450, f_T = 100MHz, SOT23 package, non-AEC-Q101	Higher gain and voltage rating, but no automotive qualification; lower f_T limits speed-critical uses	Prefer for cost-sensitive consumer designs where AEC-Q101 is unnecessary and 100MHz bandwidth is adequate.

Compared with MMBT4124-7, MMBT4401-7-F trades bandwidth for higher voltage headroom, while BC846B,215 offers broader h_FE tolerance and higher V_CEO at reduced speed and no automotive validation-making MMBT4124-7 optimal for AEC-Q101-compliant, 25V/300MHz balanced applications.

Availability

MMBT4124-7 is available at Aetrix Electronics and suitable for automotive door modules, industrial sensor interfaces, consumer audio amplifiers, and power supply enable circuits requiring stable component supply and AEC-Q101 compliance.

Supply support for MMBT4124-7 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, headquartered in Plano, Texas, with design and manufacturing operations across Asia and the Americas.

The MMBT4124-7 belongs to Diodes' AEC-Q101-qualified small-signal transistor product line, engineered for robust performance in automotive body electronics and industrial control systems where reliability under thermal and electrical stress is critical.

FAQ

Is MMBT4124-7 suitable for linear amplification applications?

Yes. With h_FE = 120–360 at I_C = 2mA and f_T = 300MHz, it supports stable small-signal amplification in common-emitter and emitter-follower configurations up to 20kHz. Its low V_CE(sat) and tight gain distribution ensure predictable biasing in audio preamp and sensor buffer stages.

What is the maximum operating temperature for continuous use?

The MMBT4124-7 has an operating junction temperature range of –55°C to +150°C. For continuous operation at full 200mA collector current, thermal design must maintain T_J ≤ 150°C using appropriate PCB copper area and airflow; derating begins above +25°C ambient per the 403°C/W R_θJA spec.

Does MMBT4124-7 have a complementary PNP part?

Yes. The MMBT4126 is the designated complementary PNP transistor, sharing identical SOT23 packaging, AEC-Q101 qualification, and matched voltage/current ratings (V_CEO = 25V, I_C = –200mA), enabling use in push-pull output stages and differential pair circuits.

Can MMBT4124-7 be used in high-frequency switching above 10MHz?

It can operate reliably up to ~10MHz in saturated switching due to its 300MHz f_T and 4.0pF C_obo, but gate drive strength and layout parasitics become dominant above this frequency. For >20MHz digital switching, dedicated RF transistors or MOSFETs with lower C_iss are recommended.

MMBT4124-7 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 FAQ

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

Please submit a Request for Quotation (RFQ) for MMBT4124-7 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 reliable?

The price and inventory of MMBT4124-7 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 is usually 5 days.

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

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

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for MMBT4124-7?

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

Once your MMBT4124-7 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?

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

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

All MMBT4124-7 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 meets industry standards.

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

All MMBT4124-7 units undergo pre-shipment inspection (PSI). If there is an issue with MMBT4124-7, 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 part is unused and in its original packaging.

Return procedure for MMBT4124-7:

1.Submit a request within 90 days.

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

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