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Home > Products > Discrete Semiconductor Products > Transistors > Bipolar (BJT) > Single, Pre-Biased Bipolar Transistors

Diodes Incorporated DDTC125TUA-7-F

Name: DDTC125TUA-7-F
Brand: Diodes Incorporated
SKU: DDTC125TUA-7-F
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: DDTC125TUA-7-F

Manufacturer:: Diodes Incorporated

Category:: Single, Pre-Biased Bipolar Transistors

Package:: SC-70, SOT-323

Datasheet:: DDTC125TUA-7-F.pdf

Description:: TRANS PREBIAS NPN 50V SOT323

Quantity:: RFQ Add To RFQ list

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Inventory:8,792

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Product details

Overview

DDTC125TUA-7-F from Diodes Incorporated is an NPN pre-biased small-signal transistor with a single built-in 200 kΩ bias resistor (R1 only), housed in a SOT323 surface-mount package. It supports 50 V V_CEO, 100 mA I_C, 200 mW power dissipation, and delivers h_FE of 100–600 at I_C = 1 mA, V_CE = 5 V - used for digital switching and level translation in space-constrained consumer and industrial control circuits.

For engineers reviewing the DDTC125TUA-7-F datasheet, DDTC125TUA-7-F pinout, DDTC125TUA-7-F application, or DDTC125TUA-7-F equivalent, key selection criteria include verified R1 tolerance (±30%), V_CE(sat) ≤ 0.3 V at multiple I_C/I_B ratios, thermal resistance (625 °C/W), AEC-Q101 eligibility status, and SOT323 footprint compatibility with automated assembly.

Technical Context

This device integrates a monolithic NPN transistor with a single external-base biasing resistor (R1), eliminating discrete base-resistor placement. Its epitaxial planar die construction ensures stable gain and low leakage, while the SOT323 package enables high-density PCB layouts with JEDEC-compliant thermal performance on FR4 boards.

The transistor operates within -55°C to +150°C ambient range and meets J-STD-020 moisture sensitivity Level 1. It is fully RoHS 3 compliant, halogen- and antimony-free ("Green"), and rated for automotive-grade change control when qualified per AEC-Q101 under IATF 16949 manufacturing.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	50 V - Maximum collector-emitter voltage before breakdown; defines safe operating range in low-voltage switching rails.
I_C (max)	100 mA - Continuous collector current limit; suitable for driving LEDs, relays, and logic-level interfaces.
P_D	200 mW - Power dissipation on FR4 board with minimum pad layout; constrains duty cycle in pulsed applications.
h_FE	100–600 - DC current gain at I_C = 1 mA, V_CE = 5 V; enables predictable saturation with defined base drive.
R1	200 kΩ ±30% - Integrated base bias resistor; reduces BOM count and layout area vs. discrete resistor + transistor.
V_CE(sat)	≤0.3 V - Confirmed at multiple I_C/I_B ratios (e.g., 10 mA/1 mA); ensures low conduction loss in saturated switch mode.
T_J Range	-55°C to +150°C - Extended junction temperature capability supports operation in automotive engine bays and industrial enclosures.

Pinout & Package

Package: SOT323 - ultra-small plastic surface-mount package (2.15 mm × 2.10 mm × 0.95 mm), UL 94V-0 rated, matte tin-plated leads, 0.006 g weight, moisture sensitivity Level 1.

Pin/Terminal	Circuit Role	Design Meaning
Emitter (E)	Current sink terminal	Connected to ground or low-side return path; defines reference for base bias network.
Base (B)	Control input node	Internally connected to R1; accepts TTL/CMOS-compatible logic levels without external pull-up/down.
Collector (C)	Switched output node	Drives load between V_CC and collector; requires no external flyback protection for resistive loads.

Key Features

Feature	Design Value
Single integrated R1 bias resistor	200 kΩ ±30% - eliminates discrete resistor placement, reduces PCB area, improves assembly yield.
Epitaxial planar die construction	Ensures tight parameter distribution and low leakage (I_CBO, I_EBO ≤ 0.5 µA) across temperature.
SOT323 surface-mount package	Enables automated pick-and-place; compatible with reflow profiles per J-STD-020 Level 1.
Halogen- and antimony-free "Green" compound	Meets <900 ppm Br, <900 ppm Cl, <1000 ppm Sb - satisfies strict environmental compliance for global OEMs.

Applications

LED Driver Circuit

Microcontroller GPIO Expander

Use Scenario: Driving 20 mA indicator LEDs from 3.3 V or 5 V MCU outputs in portable instrumentation.

IC Role / Device Role / Timing Role: NPN switch enabling low-side LED current control with fixed base bias.

Use Value: Eliminates need for external base resistor; V_CE(sat) ≤ 0.3 V minimizes voltage drop and heat generation at 20 mA.

Use Scenario: Extending digital I/O count using discrete transistors to interface with legacy peripherals.

IC Role / Device Role / Timing Role: Level-shifting and current-boosting buffer for open-drain or weak-drive signals.

Use Value: h_FE ≥ 100 ensures reliable saturation with 0.1–1 mA base drive; SOT323 footprint saves board space.

Power Supply Enable Switch

Industrial Sensor Interface

Use Scenario: Enabling/disabling 12 V auxiliary rails via microcontroller command in programmable power modules.

IC Role / Device Role / Timing Role: Low-side enable switch controlling PMOS gate or LDO EN pin.

Use Value: 50 V V_CEO provides margin above 12 V rail; 100 mA rating supports typical enable currents ≤ 5 mA.

Use Scenario: Conditioning analog sensor outputs (e.g., thermistor dividers) before ADC input in factory automation nodes.

IC Role / Device Role / Timing Role: Signal conditioning switch isolating sensor bias during sleep mode.

Use Value: -55°C to +150°C operating range matches industrial sensor ambient requirements; low I_CBO prevents false triggering.

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN pre-biased transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
DDTC124TUA-7-F	R1 = 22 kΩ (vs. 200 kΩ); higher base current, lower h_FE sensitivity to R1 tolerance	Better suited for 5 V logic-driven loads requiring faster turn-on; less ideal for 3.3 V or battery-powered systems	Select when driving heavier loads (>20 mA) with stronger base drive available.
NSV125T1T5G	Same R1 = 200 kΩ, but SOT-523 package (smaller); h_FE min = 80; AEC-Q101 qualified	Valid for automotive applications requiring PPAP documentation; not recommended for manual rework due to smaller footprint	Choose for AEC-Q101-compliant designs where space is critical and supply chain traceability is required.

Compared with DDTC124TUA-7-F and NSV125T1T5G, DDTC125TUA-7-F offers optimal base bias for low-current 3.3 V logic switching in cost-sensitive industrial designs, while retaining full RoHS 3 and "Green" compliance without automotive qualification overhead.

Availability

DDTC125TUA-7-F is available at Aetrix Electronics and suitable for LED driver circuits, microcontroller GPIO expansion, and power supply enable switching requiring stable component supply and long-term obsolescence management.

Supply support for DDTC125TUA-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, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.

The DDTC (R1-Only Series) UA product line delivers pre-biased NPN transistors optimized for simplified digital switching in space-constrained, high-volume consumer and industrial applications - emphasizing BOM reduction, automated assembly readiness, and environmental compliance.

FAQ

Is DDTC125TUA-7-F still in active production?

No - DDTC125TUA-7-F is marked "Obsolete" in Diodes' official ordering information. However, Aetrix Electronics maintains legacy inventory and offers lifecycle management services including cross-reference support, last-time buy coordination, and alternative sourcing guidance for ongoing production needs.

What is the exact marking code on the DDTC125TUA-7-F package?

The top-side marking is "N25", per Diodes' DS30323 Rev. 9–2 datasheet. This two-character code identifies the DDTC125TUA variant within the R1-only series and is laser-etched on the SOT323 body for traceability and visual verification during inspection.

Can DDTC125TUA-7-F be used in automotive applications?

DDTC125TUA-7-F itself is not AEC-Q101 qualified, though it is manufactured in IATF 16949-certified facilities. For automotive use, Diodes recommends contacting their applications team to explore qualified alternatives like NSV125T1T5G, which carries full AEC-Q101 certification and PPAP documentation.

What is the thermal resistance (R_θJA) and how is it measured?

R_θJA is 625 °C/W, measured with the device mounted on a standard FR4 printed circuit board using Diodes' minimum recommended copper pad layout per DS30323. This value reflects junction-to-ambient conduction under natural convection and is valid only when PCB layout adheres to specified thermal pad dimensions and copper area.

DDTC125TUA-7-F Specifications

Product attributes: Attribute value

Manufacturer:: Diodes Incorporated

Series:: -

Package/Case:: SC-70, SOT-323

Packaging:: Tape & Reel (TR)

Product Status:: Obsolete

Transistor Type:: NPN - Pre-Biased

Current - Collector (Ic) (Max):: 100 mA

Voltage - Collector Emitter Breakdown (Max):: 50 V

Resistor - Base (R1):: 200 kOhms

Resistor - Emitter Base (R2):: -

DC Current Gain (hFE) (Min) @ Ic, Vce:: 100 @ 1mA, 5V

Vce Saturation (Max) @ Ib, Ic:: 300mV @ 50µA, 500µA

Current - Collector Cutoff (Max):: 500nA (ICBO)

Frequency - Transition:: 250 MHz

Power - Max:: 200 mW

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: SOT-323

DDTC125TUA-7-F FAQ

1.How can I place an order for DDTC125TUA-7-F through Aetrix?

Please submit a Request for Quotation (RFQ) for DDTC125TUA-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 DDTC125TUA-7-F reliable?

The price and inventory of DDTC125TUA-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 DDTC125TUA-7-F is usually 5 days.

3.What payment methods are accepted for DDTC125TUA-7-F?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for DDTC125TUA-7-F transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for DDTC125TUA-7-F?

DDTC125TUA-7-F orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your DDTC125TUA-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 DDTC125TUA-7-F?

For technical support, including DDTC125TUA-7-F datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your DDTC125TUA-7-F requirements.

6.How does Aetrix verify that DDTC125TUA-7-F is sourced from the original manufacturer or authorized distributors?

All DDTC125TUA-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 DDTC125TUA-7-F meets industry standards.

7.What is the process for return or replacement of DDTC125TUA-7-F?

All DDTC125TUA-7-F units undergo pre-shipment inspection (PSI). If there is an issue with DDTC125TUA-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 DDTC125TUA-7-F part is unused and in its original packaging.

Return procedure for DDTC125TUA-7-F:

1.Submit a request within 90 days.

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

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