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

Diodes Incorporated FMMT591ATC

Name: FMMT591ATC
Brand: Diodes Incorporated
SKU: FMMT591ATC
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: FMMT591ATC

Manufacturer:: Diodes Incorporated

Category:: Single Bipolar Transistors

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

Datasheet:: FMMT591ATC.pdf

Description:: TRANS PNP 40V 1A SOT-23-3

Quantity:: RFQ Add To RFQ list

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Inventory:8,961

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Product details

Overview

FMMT591ATC from Diodes Incorporated is a 40V PNP medium-power transistor in SOT23 package, designed for high-current switching with -1A continuous collector current, -500mV V_CE(sat) at -1A, and 350mΩ equivalent on-resistance. It serves as a power MOSFET gate driver and low-loss power switch in compact DC-DC converters and motor control stages.

For engineers reviewing the FMMT591ATC datasheet, FMMT591ATC pinout, FMMT591ATC application, or FMMT591ATC equivalent, key selection criteria include guaranteed -40V V_CEO, pulsed -2A I_CM, thermal resistance of 197°C/W (junction-to-lead), ESD HBM rating of 4kV, and complementary pairing with FMMT491A for push-pull designs.

Technical Context

This PNP bipolar junction transistor operates in saturation or active mode for discrete switching and linear regulation. Its -40V V_CEO and -7V V_EBO support robust biasing in negative-rail circuits, while h_FE ranging from 30 to 800 across IC = -1mA to -2A enables predictable gain control in both low- and high-current drive stages.

With f_t = 150MHz at V_CE = -10V and I_C = -50mA, it supports fast switching in PWM-driven loads; td/tr/ts/tf values (34.9ns/19.2ns/249ns/62ns) confirm suitability for sub-100ns transition timing in gate-driving applications.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	-40V - Ensures safe operation in 24V and 36V negative-rail systems with margin against transients
I_C (cont.)	-1A - Supports sustained load switching in automotive body electronics and industrial IO modules
V_CE(sat)	<-500mV @ -1A - Minimizes conduction loss and self-heating during high-duty-cycle operation
R_sat	350mΩ - Enables direct comparison with logic-level MOSFETs for low-voltage gate drive
f_t	150MHz - Validates use in high-frequency switching nodes up to ~10MHz practical bandwidth
ESD HBM	4,000V - Provides handling robustness during PCB assembly without additional protection circuitry
P_D	500mW - Defines maximum steady-state dissipation on standard FR-4 with 15mm×15mm copper pad

Pinout & Package

Package: SOT23 (Type DN), surface-mount plastic package with matte tin-plated leads, moisture sensitivity level 1, weight ≈ 0.008g.

Pin/Terminal	Circuit Role	Design Meaning
1 (Emitter)	Current source terminal	Connected to positive supply rail in high-side switch configurations; requires stable voltage reference
2 (Base)	Control input	Receives TTL- or CMOS-compatible drive; -100mA base current required for full saturation at -1A
3 (Collector)	Load connection node	Sinks current to ground or negative rail; thermally coupled to PCB via lead for R_θJL = 197°C/W

Key Features

Feature	Design Value
Low V_CE(sat)	<-500mV at -1A ensures <1.5W conduction loss in 12V gate-drive paths
High I_CM	-2A peak pulse capability supports inrush current limiting in solenoid drivers
Complementary pairing	FMMT491A NPN match enables matched push-pull output stages with symmetrical timing
Green packaging	Halogen- and antimony-free compound meets AEC-Q200 environmental requirements for automotive use
Thermal performance	R_θJL = 197°C/W allows direct thermal path to PCB copper, reducing need for heatsinking

Applications

Power MOSFET Gate Driving

Low-Loss Power Switching

Use Scenario: Driving the gate of N-channel power MOSFETs in half-bridge motor controllers.

IC Role / Device Role / Timing Role: PNP switch pulls gate low rapidly during turn-off; complements NPN pull-up stage.

Use Value: -500mV V_CE(sat) minimizes Miller plateau dwell time, enabling <100ns fall-time in 24V systems.

Use Scenario: High-side load switching in 12V/24V automotive body control modules.

IC Role / Device Role / Timing Role: Serves as saturated PNP switch controlling power to lamps, relays, or sensors.

Use Value: -1A continuous rating and -40V V_CEO support ISO 7637-2 pulse immunity without derating.

DC-DC Converter Biasing

Industrial IO Module Output Stage

Use Scenario: Providing regulated bias current to error amplifiers and reference circuits in isolated flyback supplies.

IC Role / Device Role / Timing Role: Linear-mode current source delivering stable -100mA to feedback networks.

Use Value: h_FE ≥ 160 at -500mA ensures predictable current mirroring accuracy over temperature.

Use Scenario: Discrete output driver for programmable logic controller (PLC) digital outputs.

IC Role / Device Role / Timing Role: Final-stage PNP switch interfacing microcontroller GPIO to 24V field loads.

Use Value: 4kV HBM ESD rating eliminates need for external TVS diodes in factory-floor environments.

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	Higher V_CEO (-50V), lower V_CE(sat) (-350mV @ -1A), SOT89 package	Requires larger footprint; better suited for higher-voltage industrial SMPS	Select when >40V system margin or lower thermal resistance (R_θJA = 125°C/W) is critical
MMBT591A	Same die in SOT23-3 but rated for -500mA I_C; lower h_FE min (100 vs. 30)	Limited to lower-current gate driving and signal-level switching	Choose for cost-sensitive designs where -1A capability is unnecessary

Compared with ZXTN25050DFH and MMBT591A, FMMT591ATC uniquely balances -1A continuous current, -40V rating, SOT23 compactness, and 350mΩ R_sat, making it optimal for space-constrained 24V gate drivers requiring full-rated current without thermal derating.

Availability

FMMT591ATC is available at Aetrix Electronics and suitable for automotive body electronics, industrial PLC outputs, and compact DC-DC converter biasing requiring stable component supply and long-term production continuity.

Supply support for FMMT591ATC 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 computing markets.

FMMT591ATC belongs to Diodes' FMMT series of medium-power transistors, engineered for robust switching in harsh-environment applications including AEC-Q101 qualified automotive subsystems and industrial control interfaces.

FAQ

What is the maximum allowable base current for continuous operation?

The absolute maximum continuous base current is -200mA per the datasheet's Absolute Maximum Ratings table. Operation above this value risks permanent degradation of h_FE and increased V_CE(sat). For -1A collector current, -100mA base drive is sufficient and recommended to maintain saturation without overstressing the base-emitter junction.

Does FMMT591ATC meet AEC-Q101 stress test requirements?

FMMT591ATC is manufactured in IATF 16949-certified facilities and supports PPAP documentation. While not pre-qualified to AEC-Q101 in standard form, Diodes offers AEC-Q101-compliant versions (e.g., FMMT591A-Q) with full qualification reports; contact Diodes or Aetrix for automotive-grade variants and change-controlled release documentation.

Can FMMT591ATC be used in linear regulator applications?

Yes - its h_FE stability across -1mA to -1A and low V_CE(sat) support linear pass-transistor use in adjustable negative regulators. However, thermal design must account for R_θJA = 250°C/W; for >300mW dissipation, a copper pour under the collector lead is mandatory to leverage R_θJL = 197°C/W.

How does the SOT23 (Type DN) package differ from standard SOT23?

SOT23 (Type DN) has specific mechanical dimensions: D = 2.80–3.04mm, E = 2.10–2.64mm, and L1 = 0.45–0.62mm. It differs from JEDEC-standard SOT23 in leadform geometry and mold compound formulation, optimized for automated placement and reflow compatibility. Diodes' Type DN outline ensures consistent solder joint formation and mechanical reliability in high-vibration environments.

FMMT591ATC 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:: Active

Transistor Type:: PNP

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

Voltage - Collector Emitter Breakdown (Max):: 40 V

Vce Saturation (Max) @ Ib, Ic:: 500mV @ 100mA, 1A

Current - Collector Cutoff (Max):: 100nA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 300 @ 100mA, 5V

Power - Max:: 500 mW

Frequency - Transition:: 150MHz

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

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: SOT-23-3

FMMT591ATC FAQ

1.How can I place an order for FMMT591ATC through Aetrix?

Please submit a Request for Quotation (RFQ) for FMMT591ATC 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 FMMT591ATC reliable?

The price and inventory of FMMT591ATC are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for FMMT591ATC is usually 5 days.

3.What payment methods are accepted for FMMT591ATC?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for FMMT591ATC transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for FMMT591ATC?

FMMT591ATC orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your FMMT591ATC 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 FMMT591ATC?

For technical support, including FMMT591ATC datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your FMMT591ATC requirements.

6.How does Aetrix verify that FMMT591ATC is sourced from the original manufacturer or authorized distributors?

All FMMT591ATC 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 FMMT591ATC meets industry standards.

7.What is the process for return or replacement of FMMT591ATC?

All FMMT591ATC units undergo pre-shipment inspection (PSI). If there is an issue with FMMT591ATC, 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 FMMT591ATC part is unused and in its original packaging.

Return procedure for FMMT591ATC:

1.Submit a request within 90 days.

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

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