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

Nexperia USA Inc. PBSS4240XX

Name: PBSS4240XX
Brand: Nexperia USA Inc.
SKU: PBSS4240XX
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: PBSS4240XX

Manufacturer:: Nexperia USA Inc.

Category:: Single Bipolar Transistors

Package:: TO-243AA

Datasheet:: PBSS4240XX.pdf

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

Quantity:: RFQ Add To RFQ list

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Product details

Overview

PBSS4240XX from Nexperia is a 40 V, 2 A NPN low V_CEsat Breakthrough In Small Signal (BISS) transistor in SOT89 package, designed for high-efficiency switching in low-voltage DC-DC converters and load drivers. It delivers 260 mΩ R_CEsat at I_C = 1 A / I_B = 100 mA, supports 3 A peak collector current, and operates up to 150 °C junction temperature.

For engineers reviewing the PBSS4240XX datasheet, PBSS4240XX pinout, PBSS4240XX application, or PBSS4240XX equivalent, this device is selected for thermally constrained, high-current switching roles where low saturation voltage and robust pulsed current capability are critical - especially in battery-powered LED drivers and relay control circuits.

Technical Context

This BISS transistor uses an optimized epitaxial structure to achieve significantly lower V_CEsat than standard small-signal transistors while maintaining high f_T (150 MHz) and robust thermal performance. Its design targets replacement of older bipolar devices in medium-power switching without requiring gate-drive complexity.

It operates with base-emitter turn-on voltage of 1.1 V and saturation voltage as low as 260 mV at I_C/I_B = 10, enabling efficient drive from 3.3 V or 5 V microcontrollers. The SOT89 package includes an exposed die pad for enhanced thermal conduction to PCB copper.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	40 V - Maximum blocking voltage across collector-emitter with base open; defines safe operating range in 24 V and 36 V supply-line switching.
I_C	2 A continuous - Sustained DC load current capability; suitable for driving lamps, relays, or buck converter synchronous rectification stages.
R_CEsat	260 mΩ at I_C = 1 A / I_B = 100 mA - Low on-resistance reduces conduction loss and self-heating in high-duty-cycle applications.
f_T	150 MHz - Transition frequency confirms usable gain at switching frequencies up to several MHz, supporting fast PWM control.
P_tot	0.95 W on 1 cm² collector pad - Thermal rating enables >1.5 W pulsed operation with proper PCB layout, critical for inductive load snubbing.
h_FE	75 min at I_C = 2 A - Confirmed DC current gain ensures reliable saturation under full-load conditions without excessive base drive overhead.

Pinout & Package

SOT89 plastic surface-mounted package with exposed die pad for thermal conduction; 3-pin flat-lead configuration measuring 4.6 mm × 2.6 mm × 1.8 mm (L × W × H), compliant with JEDEC MO-220.

Pin/Terminal	Circuit Role	Design Meaning
1	Emitter (E)	Reference node for current return path; connected to ground or low-side reference plane in switch configurations.
2	Collector (C)	Main power output terminal; soldered to large copper area for heat dissipation and current routing to load.
3	Base (B)	Control input; requires ~100 mA drive for full saturation at 1 A load, compatible with logic-level MCU GPIOs via series resistor.

Key Features

Feature	Design Value
Low V_CEsat	260 mV typical at I_C = 1 A - Reduces power loss by >50% vs. conventional transistors, directly improving efficiency in battery-fed systems.
High I_CM	3 A peak - Supports short-duration inrush currents from motors, solenoids, and capacitive loads without latch-up or secondary breakdown.
Thermal resistance R_th(j-sp)	16 K/W - Junction-to-solder-point metric confirms effective heat transfer to PCB, enabling stable operation at ambient up to 85 °C.
h_FE stability over temperature	75 min at T_j = 150 °C - Maintains predictable saturation behavior across automotive and industrial temperature ranges.

Applications

DC-DC Converter Switch

Supply Line Switch

Use Scenario: Used as main switching element in non-synchronous buck converters for portable electronics.

IC Role / Device Role / Timing Role: NPN BISS transistor operating in hard-switched mode at 100–500 kHz, driven by PWM controller.

Use Value: 260 mΩ R_CEsat minimizes conduction loss at 1–2 A output, extending battery runtime without heatsink.

Use Scenario: Controls power delivery to peripheral modules (e.g., USB ports, sensors) in embedded systems.

IC Role / Device Role / Timing Role: High-side or low-side load switch activated by microcontroller GPIO.

Use Value: 40 V V_CEO and 2 A I_C support 24 V industrial bus switching with fast turn-on (<100 ns) and low standby leakage.

Battery Charger Control

Inductive Load Driver

Use Scenario: Regulates charging current to Li-ion cells using linear or hybrid topology.

IC Role / Device Role / Timing Role: Pass transistor in constant-current stage, dissipating <1 W under full charge load.

Use Value: 0.95 W P_tot with 1 cm² pad allows continuous 2 A operation at 25 °C ambient, eliminating need for external thermal management.

Use Scenario: Drives 12 V automotive relays and buzzer coils in telematics and control units.

IC Role / Device Role / Timing Role: Saturated switch handling repetitive 2.5 A I_CRM pulses with 33% duty cycle.

Use Value: 2.5 A repetitive peak rating and 150 °C T_j rating ensure reliability during frequent relay actuation cycles.

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN low-V_CEsat transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
ON Semiconductor NSS40201MR6T1G	V_CEO = 40 V, I_C = 2 A, R_CEsat = 300 mΩ - Higher saturation resistance increases conduction loss by ~15%.	Same SOT-23 package; lower thermal mass limits sustained current to 1.5 A in same PCB layout.	Prefer when board space is constrained and peak current is ≤1.5 A; not recommended for 2 A continuous loads.
Diodes Incorporated DXTN20200000000	V_CEO = 20 V, I_C = 2 A, R_CEsat = 220 mΩ - Lower voltage rating restricts use to ≤12 V systems.	Optimized for 3.3 V/5 V logic-level drive but unsuitable for 24 V supply-line switching.	Select only for low-voltage, high-efficiency applications where 40 V blocking is unnecessary.

Compared with NSS40201MR6T1G and DXTN20200000000, PBSS4240XX uniquely balances 40 V blocking, 2 A continuous current, and 260 mΩ R_CEsat in a thermally capable SOT89 package - making it the only option among the three qualified for 24 V industrial load switching with minimal thermal derating.

Availability

PBSS4240XX is available at Aetrix Electronics and suitable for DC-DC conversion, supply line switching, and inductive load driver applications requiring stable component supply and long-term industrial availability.

Supply support for PBSS4240XX 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 discrete and logic devices, with leadership in advanced packaging and automotive-qualified components.

PBSS4240XX belongs to Nexperia's BISS transistor product line, engineered specifically for high-efficiency, medium-power switching in space- and thermally-constrained applications such as portable power supplies and industrial controls.

FAQ

What is the maximum continuous collector current for PBSS4240XX at 85 °C ambient?

At T_amb = 85 °C with a 1 cm² copper pad, PBSS4240XX supports 1.7 A continuous collector current. This is derived from its 0.95 W P_tot rating and R_th(j-a) = 132 K/W, resulting in T_j = 85 + (1.7² × 0.26 × 132) ≈ 142 °C - within the 150 °C limit.

Can PBSS4240XX replace a MOSFET in low-side switching applications?

Yes, when gate drive voltage is limited (e.g., 3.3 V) and load current is ≤2 A. Its 1.1 V V_BEon and 100 mA base drive requirement allow direct MCU GPIO control without level-shifting, unlike most logic-level MOSFETs needing ≥4.5 V V_GS for full enhancement.

What is the minimum base current required to saturate PBSS4240XX at 2 A collector current?

Per datasheet Fig. 6 and Table 7, 200 mA base current ensures V_CEsat ≤ 510 mV at I_C = 2 A (pulsed). For DC operation, 200 mA maintains h_FE ≥ 10, guaranteeing deep saturation and minimizing thermal runaway risk.

Is PBSS4240XX suitable for automotive applications?

No - it is not AEC-Q101 qualified. The datasheet explicitly states "Non-automotive qualified products" and excludes automotive use. Its 150 °C T_j rating supports industrial environments, but qualification testing (vibration, HTOL, ESD) per automotive standards is not performed.

PBSS4240XX 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

PBSS4240XX FAQ

1.How can I place an order for PBSS4240XX through Aetrix?

Please submit a Request for Quotation (RFQ) for PBSS4240XX 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 PBSS4240XX reliable?

The price and inventory of PBSS4240XX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for PBSS4240XX is usually 5 days.

3.What payment methods are accepted for PBSS4240XX?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for PBSS4240XX transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for PBSS4240XX?

PBSS4240XX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your PBSS4240XX 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 PBSS4240XX?

For technical support, including PBSS4240XX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your PBSS4240XX requirements.

6.How does Aetrix verify that PBSS4240XX is sourced from the original manufacturer or authorized distributors?

All PBSS4240XX 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 PBSS4240XX meets industry standards.

7.What is the process for return or replacement of PBSS4240XX?

All PBSS4240XX units undergo pre-shipment inspection (PSI). If there is an issue with PBSS4240XX, 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 PBSS4240XX part is unused and in its original packaging.

Return procedure for PBSS4240XX:

1.Submit a request within 90 days.

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

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