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 FZT549TC

Name: FZT549TC
Brand: Diodes Incorporated
SKU: FZT549TC
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: FZT549TC

Manufacturer:: Diodes Incorporated

Category:: Single Bipolar Transistors

Package:: TO-261-4, TO-261AA

Datasheet:: FZT549TC.pdf

Description:: TRANS PNP 30V 1A SOT-223-3

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:7,154

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

Product details

Overview

FZT549TC from Diodes Incorporated is a 30V PNP medium-power transistor in SOT223 package, rated for -1A continuous collector current, with V_CE(sat) < -0.5V at -1A and h_FE up to 300 at -50mA, used in automotive load switching and industrial DC-DC converter bias circuits.

For engineers reviewing the FZT549TC datasheet, FZT549TC pinout, FZT549TC application, or FZT549TC equivalent, key selection criteria include guaranteed -30V V_CEO, AEC-Q101 qualification, thermal resistance of 41.7°C/W on 50mm×50mm copper, and low saturation voltage under high-current switching conditions.

Technical Context

This PNP bipolar junction transistor operates in linear or saturated switching mode with verified breakdown ratings: V_CBO = -35V, V_CEO = -30V, and V_EBO = -7V. Its h_FE spans 70–300 across IC = -50mA to -2A, supporting stable current amplification in bias networks and driver stages.

Switching performance is characterized by t_on = 50ns and t_off = 300ns at -500mA, with f_T = 100MHz at V_CE = -5V, enabling use in medium-speed power control where gain-bandwidth trade-offs are critical.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	-30V - Ensures safe operation in 24V automotive systems with transient spikes up to -30V.
I_C (cont.)	-1A - Supports sustained load switching in motor drivers and relay interfaces without derating at +25°C.
V_CE(sat)	< -0.5V @ -1A - Minimizes conduction loss and self-heating in high-duty-cycle switching applications.
h_FE	70–300 - Provides predictable base drive requirements across operating current range from 50mA to 2A.
R_θJA	41.7°C/W - Enables 3W power dissipation on 50mm×50mm 2oz copper PCB, critical for thermally constrained layouts.
f_T	100MHz - Supports stable small-signal amplification and fast turn-off in feedback-controlled regulators.

Pinout & Package

Package: SOT223 - Surface-mount plastic package with exposed collector tab for thermal enhancement; 0.112g weight; UL 94V-0 flammability rating; moisture sensitivity level 1.

Pin/Terminal	Circuit Role	Design Meaning
Emitter (E)	Current source terminal	Connected to higher potential rail; carries full load current in PNP switch configuration.
Base (B)	Control input	Receives negative drive current to saturate transistor; requires ~10% I_C for full turn-on.
Collector (C)	Output/switching node	Internally connected to exposed metal tab; must be electrically and thermally tied to PCB ground plane or heatsink.
Tab (Collector)	Thermal & electrical path	Provides primary heat conduction path; electrically identical to Collector pin; requires solder mask clearance per AP02001.

Key Features

Feature	Design Value
AEC-Q101 qualified	Validated for automotive underhood applications including temperature cycling, humidity, and mechanical shock per JESD47.
Lead-free & halogen-free	RoHS-compliant with Br+Cl < 1500ppm and Sb < 1000ppm; meets global environmental compliance mandates.
Low V_CE(sat)	< -0.5V at -1A ensures ≤0.5W conduction loss, reducing thermal stress in compact power stages.
High h_FE linearity	h_FE ≥70 at -1A enables reliable base drive design without excessive margin or active current limiting.

Applications

Automotive Body Control Module

Industrial DC-DC Converter Bias

Use Scenario: Driving solenoids and LED arrays in door lock actuators and interior lighting.

IC Role / Device Role / Timing Role: PNP high-side switch controlling 12V loads with microcontroller-compatible base drive.

Use Value: -30V V_CEO withstands load-dump transients; AEC-Q101 qualification ensures reliability over 15-year vehicle lifetime.

Use Scenario: Providing stable bias current to error amplifier and reference circuits in isolated flyback converters.

IC Role / Device Role / Timing Role: Linear-mode current source delivering precise, temperature-stable bias under varying input voltage.

Use Value: h_FE stability from -50mA to -1A enables consistent loop compensation without recalibration across line/load conditions.

Consumer Appliance Motor Driver

Telecom Power Sequencing

Use Scenario: Controlling brushed DC fan motors in HVAC systems and kitchen appliances.

IC Role / Device Role / Timing Role: Medium-power PNP switch interfacing MCU GPIO to motor H-bridge enable logic.

Use Value: 3W power dissipation capability allows direct mounting on 50mm×50mm copper without external heatsink.

Use Scenario: Enabling multi-rail power supplies in base station RF modules with strict sequencing timing.

IC Role / Device Role / Timing Role: Discrete timing element in RC-delayed enable circuit for 3.3V/5V/12V rail sequencing.

Use Value: Low C_obo (10pF) and fast t_off (300ns) ensure accurate, jitter-free delay generation independent of supply ripple.

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP medium-power transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
ZXTN25050DFH	V_CEO = -50V, h_FE = 100–300 @ -1A, SOT223 package, but not AEC-Q101 qualified.	Suitable for industrial/commercial designs where automotive qualification is not required.	Select when higher breakdown margin is needed and AEC-Q101 is unnecessary.
MJD2955T4G	V_CEO = -60V, I_C = -10A, TO-220 package, significantly larger footprint and higher thermal mass.	Used in high-current linear regulators where SOT223 thermal limits are exceeded.	Choose only when >1A continuous current or >3W dissipation is required; not drop-in compatible.

Compared with ZXTN25050DFH and MJD2955T4G, FZT549TC uniquely balances AEC-Q101 compliance, SOT223 thermal efficiency, and -1A capability-making it optimal for space-constrained automotive and industrial switching where qualification and board area are co-critical.

Availability

FZT549TC is available at Aetrix Electronics and suitable for automotive body control modules, industrial DC-DC converter bias circuits, and consumer appliance motor drivers requiring stable component supply and long-term lifecycle support.

Supply support for FZT549TC 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 power management, signal integrity, and protection devices.

FZT549TC belongs to Diodes' AEC-Q101-qualified medium-power transistor product line, designed specifically for automotive and industrial applications demanding robustness, thermal efficiency, and consistent parametric performance across temperature.

FAQ

What is the maximum continuous collector current for FZT549TC?

The FZT549TC is rated for -1A continuous collector current at +25°C ambient with proper PCB copper area (50mm×50mm 2oz). Derating applies above +25°C per the R_θJA = 41.7°C/W curve; at +100°C ambient, max I_C drops to approximately -0.6A to maintain T_J ≤ +150°C.

Is FZT549TC pin-compatible with other SOT223 PNP transistors?

FZT549TC uses standard SOT223 pinout (Emitter-Base-Collector-Tab), matching industry convention. However, electrical parameters-including h_FE profile, V_CE(sat), and f_T-differ from alternatives like ZXTN25050DFH; layout compatibility does not guarantee functional interchangeability without circuit validation.

Does FZT549TC require a heatsink in typical applications?

No external heatsink is required when mounted on ≥50mm×50mm 2oz copper per Diodes' thermal test condition. The exposed collector tab provides sufficient thermal conduction; heatsinking is only necessary if PCB copper area is reduced below this or ambient exceeds +85°C with >2W dissipation.

What is the significance of the "TC" suffix in FZT549TC?

The "TC" suffix denotes tape-and-reel packaging per Diodes' ordering nomenclature: FZT549TA is the AEC-Q101-compliant version in 1,000-unit reels (7-inch, 12mm tape); "TC" is an internal variant designation aligned with that qualified part, indicating identical die, qualification, and performance-used for specific distribution channel tracking.

FZT549TC Specifications

Product attributes: Attribute value

Manufacturer:: Diodes Incorporated

Series:: -

Package/Case:: TO-261-4, TO-261AA

Packaging:: Tape & Reel (TR)

Product Status:: Obsolete

Transistor Type:: PNP

Current - Collector (Ic) (Max):: 1 A

Voltage - Collector Emitter Breakdown (Max):: 30 V

Vce Saturation (Max) @ Ib, Ic:: 750mV @ 200mA, 2A

Current - Collector Cutoff (Max):: 100nA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 100 @ 500mA, 2V

Power - Max:: 2 W

Frequency - Transition:: 100MHz

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

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: SOT-223-3

FZT549TC FAQ

1.How can I place an order for FZT549TC through Aetrix?

Please submit a Request for Quotation (RFQ) for FZT549TC 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 FZT549TC reliable?

The price and inventory of FZT549TC are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for FZT549TC is usually 5 days.

3.What payment methods are accepted for FZT549TC?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for FZT549TC transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for FZT549TC?

FZT549TC orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your FZT549TC 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 FZT549TC?

For technical support, including FZT549TC datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your FZT549TC requirements.

6.How does Aetrix verify that FZT549TC is sourced from the original manufacturer or authorized distributors?

All FZT549TC 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 FZT549TC meets industry standards.

7.What is the process for return or replacement of FZT549TC?

All FZT549TC units undergo pre-shipment inspection (PSI). If there is an issue with FZT549TC, 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 FZT549TC part is unused and in its original packaging.

Return procedure for FZT549TC:

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…