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

Nexperia USA Inc. PXTA42-QX

Name: PXTA42-QX
Brand: Nexperia USA Inc.
SKU: PXTA42-QX
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: PXTA42-QX

Manufacturer:: Nexperia USA Inc.

Category:: Single Bipolar Transistors

Package:: TO-243AA

Datasheet:: PXTA42-QX.pdf

Description:: TRANS NPN 300V 0.1A SOT-89

Quantity:: RFQ Add To RFQ list

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Inventory:1,000

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Product details

Overview

PXTA42-QX from Nexperia is a 300 V, 100 mA NPN high-voltage transistor in SOT89 (SC-62) package, designed for switching applications requiring high breakdown voltage and AEC-Q101 qualification. It delivers DC current gain (h_FE) ≥40 at I_C = 30 mA, V_CE = 10 V, and supports peak collector current up to 200 mA. Used in automotive motor management and LED chain drivers.

For engineers reviewing the PXTA42-QX datasheet, PXTA42-QX pinout, PXTA42-QX application, or PXTA42-QX equivalent, key selection criteria include V_CEO = 300 V, I_C = 100 mA, h_FE ≥40, thermal resistance R_th(j-sp) = 16 K/W, and AEC-Q101 qualification for automotive-grade reliability.

Technical Context

This NPN bipolar junction transistor operates as a high-voltage switch with open-base collector-emitter breakdown voltage rated at 300 V and emitter-base voltage limit of 6 V. Its DC current gain is specified at 40 minimum under 30 mA collector current and 10 V V_CE, supporting stable amplification or saturation switching in demanding environments.

Thermal performance is defined for FR4 PCB mounting with 6 cm² collector pad: total power dissipation is 1.3 W at T_amb ≤ 25 °C, and junction-to-solder-point thermal resistance is 16 K/W - enabling robust thermal coupling in compact SMT layouts.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	300 V - maximum safe collector-emitter voltage with base open; enables use in 277 V AC line-derived circuits and HID lamp ballasts.
I_C	100 mA continuous - defines steady-state load drive capability for LED chains and telecom hook switches.
h_FE	≥40 at V_CE = 10 V, I_C = 30 mA - ensures sufficient base drive efficiency for low-power control logic interfacing.
V_CE(sat)	≤500 mV - low saturation voltage minimizes conduction loss and self-heating during switching duty cycles.
R_th(j-sp)	16 K/W - junction-to-solder-point thermal resistance confirms effective heat transfer to PCB copper, critical for sustained 1.3 W operation.
AEC-Q101	Qualified - meets stress test requirements for discrete semiconductors in automotive applications including temperature cycling and HTRB.

Pinout & Package

SOT89 (SC-62) plastic surface-mounted package: 3 leads, 1.5 mm pitch, 4.5 mm × 2.5 mm × 1.5 mm body; collector tab forms thermal and electrical connection to PCB pad.

Pin/Terminal	Circuit Role	Design Meaning
1	Emitter (E)	Current return path; connected to ground or low-side reference in common-emitter switching configurations.
2	Collector (C)	High-voltage output node; electrically and thermally coupled to PCB copper via exposed tab for power handling.
3	Base (B)	Control input; requires current-limited drive (I_B ≤ 2 mA typical for I_C = 20 mA) to ensure saturation without overdrive.

Key Features

Feature	Design Value
High-voltage blocking	V_CEO = 300 V supports direct interface with 230/277 V AC-derived rails without external snubbers.
AEC-Q101 qualification	Validated for automotive motor management and lighting systems per stress test requirements.
Medium-power SOT89 package	Enables >1 W power dissipation with minimal board area and standard reflow/wave soldering compatibility.
Low V_CE(sat)	≤500 mV reduces conduction losses and improves efficiency in LED driver and SMPS primary-side switching.

Applications

Electronic Ballast for Fluorescent Lighting

LED Driver for LED Chain Module

Use Scenario: High-frequency switching in series-resonant ballast circuits driving T5/T8 lamps.

IC Role / Device Role / Timing Role: NPN high-voltage switch controlling resonant tank current; replaces older TO-92 transistors with improved thermal performance.

Use Value: 300 V V_CEO withstands lamp ignition transients; 16 K/W R_th(j-sp) sustains 1.3 W dissipation during extended operation.

Use Scenario: Constant-current switching regulator for 12–24 V LED strings in architectural and signage lighting.

IC Role / Device Role / Timing Role: Primary-side switch in buck or flyback topology; driven by PWM controller with base current limiting.

Use Value: h_FE ≥40 ensures reliable turn-on with microcontroller GPIO-level drive; low V_CE(sat) maintains >92% efficiency at 100 mA load.

Automotive Motor Management

Switch Mode Power Supply (SMPS)

Use Scenario: Window lift, seat adjuster, and HVAC blower motor control in 12 V/24 V vehicle systems.

IC Role / Device Role / Timing Role: Low-side driver for brushed DC motors; handles inductive kickback with integrated clamp design margin.

Use Value: AEC-Q101 qualification guarantees operation across –40 °C to +150 °C ambient; 200 mA I_CM accommodates motor surge currents.

Use Scenario: Auxiliary supply or bias winding switch in offline AC-DC converters up to 30 W.

IC Role / Device Role / Timing Role: Secondary-side synchronous rectifier or primary-side startup switch in quasi-resonant flyback designs.

Use Value: 300 V rating allows direct connection to rectified mains; 1.3 W P_tot supports continuous operation without heatsink in compact adapters.

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN high-voltage switching applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
BCV46,115	V_CEO = 300 V, I_C = 100 mA, but h_FE = 100–300 (higher gain), SOT23 package (lower power: 0.25 W).	Limited to low-power signal switching; unsuitable for >0.3 W continuous dissipation or automotive under-hood use.	Select only for non-automotive, low-current bias or logic-level interface where thermal load is negligible.
PHPT60303SQ	V_CEO = 300 V, I_C = 150 mA, h_FE = 100–300, SOT89 package, AEC-Q101 qualified, P_tot = 2.5 W.	Higher current and power capability; larger die size increases cost and footprint slightly.	Choose when >100 mA average current or >1.3 W dissipation is required; otherwise PXTA42-QX offers better cost/performance balance.

Compared with BCV46,115, PXTA42-QX provides higher thermal capability and automotive qualification; versus PHPT60303SQ, it trades lower power rating for reduced cost and smaller thermal footprint in 100 mA-class applications.

Availability

PXTA42-QX is available at Aetrix Electronics and suitable for electronic ballasts, LED chain drivers, automotive motor controllers, and auxiliary SMPS requiring stable component supply and AEC-Q101 compliance.

Supply support for PXTA42-QX 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 automotive-qualified components and energy-efficient solutions.

The PXTA42-QX belongs to Nexperia's high-voltage bipolar transistor product line, engineered specifically for robust switching in automotive lighting, industrial power supplies, and telecom infrastructure where voltage resilience and thermal stability are critical.

FAQ

What is the maximum allowable junction temperature for PXTA42-QX?

The absolute maximum junction temperature (T_j) is 150 °C, as defined in the Absolute Maximum Ratings table. Operation above this temperature risks permanent device degradation. Derating is required above 25 °C ambient, based on R_th(j-a) = 96 K/W and R_th(j-sp) = 16 K/W depending on PCB layout and copper area.

Is PXTA42-QX pin-compatible with its PNP complement PXTA92-Q?

Yes - both share identical SOT89 pinning: Pin 1 = Emitter, Pin 2 = Collector, Pin 3 = Base. However, polarity reversal means circuit topology must be adapted: PXTA92-Q requires inverted biasing and complementary placement in push-pull or H-bridge configurations.

Can PXTA42-QX be used in linear amplifier mode?

No - it is optimized for switching operation. Its h_FE variation across I_C and V_CE, combined with limited f_T (50 MHz) and lack of small-signal linearity characterization, makes it unsuitable for analog amplification. Use dedicated RF or audio transistors instead.

What is the meaning of the marking code '%1D' on PXTA42-QX devices?

The marking '%1D' consists of a placeholder '%' for the manufacturing site code, '1' indicating the device variant, and 'D' denoting the date code (week/year). This matches Nexperia's standardized SOT89 top-side marking convention and enables full traceability back to wafer lot and assembly batch.

PXTA42-QX 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):: 100 mA

Voltage - Collector Emitter Breakdown (Max):: 300 V

Vce Saturation (Max) @ Ib, Ic:: 500mV @ 2mA, 20mA

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

DC Current Gain (hFE) (Min) @ Ic, Vce:: 40 @ 30mA, 10V

Power - Max:: 1.3 W

Frequency - Transition:: 50MHz

Operating Temperature:: 150°C (TJ)

Grade:: Automotive

Qualification:: AEC-Q101

Mounting Type:: Surface Mount

Supplier Device Package:: SOT-89

PXTA42-QX FAQ

1.How can I place an order for PXTA42-QX through Aetrix?

Please submit a Request for Quotation (RFQ) for PXTA42-QX 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 PXTA42-QX reliable?

The price and inventory of PXTA42-QX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for PXTA42-QX is usually 5 days.

3.What payment methods are accepted for PXTA42-QX?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for PXTA42-QX transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for PXTA42-QX?

PXTA42-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your PXTA42-QX 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 PXTA42-QX?

For technical support, including PXTA42-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your PXTA42-QX requirements.

6.How does Aetrix verify that PXTA42-QX is sourced from the original manufacturer or authorized distributors?

All PXTA42-QX 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 PXTA42-QX meets industry standards.

7.What is the process for return or replacement of PXTA42-QX?

All PXTA42-QX units undergo pre-shipment inspection (PSI). If there is an issue with PXTA42-QX, 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 PXTA42-QX part is unused and in its original packaging.

Return procedure for PXTA42-QX:

1.Submit a request within 90 days.

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

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