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

Nexperia USA Inc. PBSS4240XF

Name: PBSS4240XF
Brand: Nexperia USA Inc.
SKU: PBSS4240XF
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: PBSS4240XF

Manufacturer:: Nexperia USA Inc.

Category:: Single Bipolar Transistors

Package:: TO-243AA

Datasheet:: PBSS4240XF.pdf

Description:: TRANS NPN 40V 2A SOT-89

Quantity:: RFQ Add To RFQ list

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Product details

Overview

PBSS4240XF from Nexperia is a 40 V, 2 A NPN low V_CE(sat) BISS (Breakthrough In Small Signal) transistor in SOT89 package, designed for high-efficiency switching in low-voltage power paths. It delivers 260 mΩ R_CE(sat) at I_C = 1 A / I_B = 100 mA, supports 3 A peak collector current, and operates up to 150 °C junction temperature - enabling compact DC-DC converters and battery-powered load drivers.

For engineers reviewing the PBSS4240XF datasheet, PBSS4240XF pinout, PBSS4240XF application, or PBSS4240XF equivalent, key selection criteria include verified V_CE(sat) ≤ 510 mV at 2 A, thermal resistance as low as 93 K/W with 6 cm² copper pad, and SOT89-compatible footprint for medium-power discrete switching where low conduction loss and thermal robustness are critical.

Technical Context

This NPN BISS transistor uses optimized epitaxial base design to achieve ultra-low saturation voltage while maintaining high DC current gain (h_FE ≥ 75 at I_C = 2 A). Its structure enables stable operation under pulsed conditions (t_p ≤ 300 µs, duty cycle ≤ 0.02) without thermal runaway.

The device is characterized for three mounting configurations: standard SOT89 footprint (R_th(j-a) = 250 K/W), 1 cm² collector pad (132 K/W), and 6 cm² pad (93 K/W), directly linking PCB layout decisions to safe operating area and continuous current capability.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	40 V - Maximum blocking voltage across collector-emitter with base open; defines safe operation in 24 V and 36 V supply rails.
I_C	2 A continuous - Sustained load current capability under 25 °C ambient with adequate heatsinking; enables direct driving of LEDs or small relays.
V_CE(sat)	510 mV max at I_C = 2 A / I_B = 200 mA - Low conduction loss reduces power dissipation by >40% vs. standard bipolar transistors at same current.
R_CE(sat)	260 mΩ typical at I_C = 1 A / I_B = 100 mA - Enables precise on-resistance modeling for thermal and efficiency calculations in switch-mode designs.
P_tot	1.35 W max with 6 cm² copper pad - Defines absolute maximum power handling; requires specific PCB copper area to achieve rated current.
h_FE	75 min at I_C = 2 A - Ensures sufficient current gain for reliable saturation with moderate base drive, reducing driver stage complexity.
f_T	150 MHz - Supports switching above 1 MHz in high-frequency DC-DC topologies without significant gain roll-off.

Pinout & Package

SOT89 plastic surface-mounted package with exposed die pad for enhanced thermal transfer; 3-pin flat-lead configuration measuring 4.6 mm × 2.6 mm × 1.8 mm (L × W × H), optimized for manual and automated assembly on FR4 PCBs.

Pin/Terminal	Circuit Role	Design Meaning
1 - E	Emitter	Reference node for current flow; connected to ground or low-side return path; electrically tied to thermal pad in PCB layout.
2 - C	Collector	Main power output terminal; requires minimum 1 cm² copper pour for thermal management; carries full load current.
3 - B	Base	Control input; driven with 100–200 mA to ensure hard saturation; sensitive to ESD and requires series resistor in most applications.

Key Features

Feature	Design Value
Low V_CE(sat)	Reduces conduction losses to ≤ 1.02 W at 2 A, enabling higher efficiency in battery-operated systems with limited thermal margin.
High I_CM	3 A peak rating allows short-duration surge handling (e.g., motor startup or relay coil energization) without secondary protection.
Thermal robustness	Junction-to-solder-point resistance of 16 K/W enables direct thermal coupling to PCB ground plane, improving reliability in industrial environments.
BISS architecture	Combines low saturation voltage with high h_FE, reducing required base drive current and simplifying gate/base driver circuitry.

Applications

DC-to-DC Conversion

Supply Line Switching

Use Scenario: Step-down converter in portable medical devices requiring <1.5 W output at 5 V/300 mA.

IC Role / Device Role / Timing Role: Main switching transistor in asynchronous buck topology, operating at 500 kHz with 30 ns turn-on delay.

Use Value: 260 mΩ R_CE(sat) limits conduction loss to 23 mW, enabling >92% efficiency without active cooling.

Use Scenario: Hot-swap control for 12 V auxiliary rail in industrial PLC backplane.

IC Role / Device Role / Timing Role: Low-side load switch enabling controlled power-up sequencing and overcurrent limiting via external sense resistor.

Use Value: 40 V V_CEO provides 3× safety margin over 12 V rail; 2 A rating supports dual-module redundancy.

Battery Charger

Inductive Load Driver

Use Scenario: Constant-current charging circuit for 2-cell Li-ion packs in handheld test equipment.

IC Role / Device Role / Timing Role: Series pass element regulating charge current with feedback from op-amp-controlled base drive.

Use Value: Stable h_FE ≥ 75 ensures predictable current regulation across -20 °C to +70 °C ambient range.

Use Scenario: Driving 24 V DC buzzer and 12 V relay coils in automotive diagnostic tool.

IC Role / Device Role / Timing Role: Single-transistor interface between microcontroller GPIO and inductive loads, with integrated flyback diode on PCB.

Use Value: 3 A I_CM safely handles 2.1 A relay inrush; 150 MHz f_T prevents oscillation during fast turn-off.

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN low-V_CE(sat) transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
DMT3006LPS-13	30 V V_CEO, 6 A I_C, SO-8 package; MOSFET-based with 22 mΩ R_DS(on).	Requires gate drive voltage >4.5 V; unsuitable for 3.3 V logic control without level shift.	Select when higher current and lower R_DS(on) justify larger footprint and gate drive complexity.
PBSS4140XF	40 V V_CEO, 1 A I_C, identical SOT89 package; 350 mΩ R_CE(sat) at 0.5 A.	Lower current rating limits use to sub-1 A loads; same thermal profile and pinout.	Choose for cost-sensitive designs where 1 A continuous current suffices and board space must be preserved.

Compared with PBSS4240XF, DMT3006LPS-13 offers lower on-resistance but demands higher gate voltage and occupies more PCB area, while PBSS4140XF maintains pin compatibility at reduced current capacity - making PBSS4240XF the optimal balance of current, thermal performance, and 3.3 V/5 V logic compatibility in SOT89.

Availability

PBSS4240XF is available at Aetrix Electronics and suitable for DC-DC conversion, supply line switching, and battery charger applications requiring stable component supply, consistent parametric performance, and long-term industrial availability.

Supply support for PBSS4240XF 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

Nexperia is a global semiconductor expert focused on high-volume, high-reliability essential semiconductors - delivering discrete, logic, and MOSFET solutions for automotive, industrial, and consumer markets.

PBSS4240XF belongs to Nexperia's BISS transistor product line, engineered specifically for high-efficiency, medium-power switching in space-constrained applications where low V_CE(sat) and thermal resilience are mandatory.

FAQ

What is the maximum continuous collector current for PBSS4240XF at 70 °C ambient?

At T_amb = 70 °C with a 6 cm² copper pad, PBSS4240XF supports 1.65 A continuous collector current. This derating is calculated from its 1.35 W P_tot rating and 93 K/W R_th(j-a), resulting in T_j = 70 °C + (1.65 A × 0.51 V) × 93 K/W ≈ 149 °C - within the 150 °C absolute maximum limit.

Does PBSS4240XF require a base resistor, and what value is recommended?

Yes - a base resistor is required to limit I_B and ensure saturation. For 5 V logic drive and I_C = 2 A, a 15 Ω resistor delivers ~233 mA I_B (accounting for V_BE(sat) ≈ 1.2 V), satisfying the I_C/I_B = 8.6 ratio needed for guaranteed V_CE(sat) ≤ 510 mV per datasheet conditions.

Can PBSS4240XF replace a standard general-purpose NPN transistor like BC817 in existing designs?

Yes, with design validation: PBSS4240XF offers significantly lower V_CE(sat) (510 mV vs. ~700 mV for BC817 at 2 A) and higher I_C rating (2 A vs. 0.5 A), but requires attention to SOT89 thermal pad layout and base drive strength due to higher I_B demand. Electrical substitution is feasible; thermal redesign may be necessary.

Is PBSS4240XF automotive qualified?

No - PBSS4240XF is not AEC-Q101 qualified and is designated for industrial and consumer applications only. Nexperia explicitly states in its legal disclaimers that non-automotive qualified products are unsuitable for automotive use, and no automotive testing or qualification data is provided for this part.

PBSS4240XF Specifications

Product attributes: Attribute value

Manufacturer:: Nexperia USA Inc.

Series:: -

Package/Case:: TO-243AA

Packaging:: Tape & Reel (TR)

Product Status:: Active

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 2 A

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

Vce Saturation (Max) @ Ib, Ic:: 140mV @ 50mA, 500mA

Current - Collector Cutoff (Max):: 100nA (ICBO)

DC Current Gain (hFE) (Min) @ Ic, Vce:: 300 @ 500mA, 5V

Power - Max:: 500 mW

Frequency - Transition:: 150MHz

Operating Temperature:: 150°C (TJ)

Grade:: Automotive

Qualification:: AEC-Q100

Mounting Type:: Surface Mount

Supplier Device Package:: SOT-89

PBSS4240XF FAQ

1.How can I place an order for PBSS4240XF through Aetrix?

Please submit a Request for Quotation (RFQ) for PBSS4240XF 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 PBSS4240XF reliable?

The price and inventory of PBSS4240XF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for PBSS4240XF is usually 5 days.

3.What payment methods are accepted for PBSS4240XF?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for PBSS4240XF transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for PBSS4240XF?

PBSS4240XF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your PBSS4240XF 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 PBSS4240XF?

For technical support, including PBSS4240XF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your PBSS4240XF requirements.

6.How does Aetrix verify that PBSS4240XF is sourced from the original manufacturer or authorized distributors?

All PBSS4240XF 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 PBSS4240XF meets industry standards.

7.What is the process for return or replacement of PBSS4240XF?

All PBSS4240XF units undergo pre-shipment inspection (PSI). If there is an issue with PBSS4240XF, 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 PBSS4240XF part is unused and in its original packaging.

Return procedure for PBSS4240XF:

1.Submit a request within 90 days.

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

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