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

Nexperia USA Inc. PMBT5550-QR

Name: PMBT5550-QR
Brand: Nexperia USA Inc.
SKU: PMBT5550-QR
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: PMBT5550-QR

Manufacturer:: Nexperia USA Inc.

Category:: Single Bipolar Transistors

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

Datasheet:: PMBT5550-QR.pdf

Description:: TRANS NPN 140V 0.3A TO-236AB

Quantity:: RFQ Add To RFQ list

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Inventory:3,000

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Product details

Overview

PMBT5550-QR from Nexperia is an AEC-Q101-qualified NPN high-voltage transistor in SOT23 package, rated for 140 V V_CEO, 300 mA I_C, and 250 mW P_tot at T_amb ≤ 25 °C; used in automotive load switching, ignition drivers, and HV bias circuits.

For engineers reviewing the PMBT5550-QR datasheet, PMBT5550-QR pinout, PMBT5550-QR application, or PMBT5550-QR equivalent, key selection criteria include V_CEO derating at elevated junction temperature, h_FE consistency across 1–50 mA I_C, saturation voltage at defined I_B/I_C ratios, thermal resistance on FR4 PCB, and AEC-Q101 qualification scope.

Technical Context

This discrete NPN transistor operates as a single-stage high-voltage switch with open-base collector-emitter breakdown of 140 V and peak collector current capability of 600 mA. Its DC current gain (h_FE) ranges from 60 at I_C = 1 mA to 20 at I_C = 50 mA, supporting stable linear and saturated switching modes.

Thermal performance is defined for FR4 PCB mounting: R_th(j-a) = 500 K/W, enabling operation up to T_j = 150 °C. Cut-off leakage (I_CBO ≤ 50 nA at 100 V, 25 °C; ≤ 50 µA at 100 °C) ensures low standby power in HV hold circuits.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	140 V - Maximum collector-emitter voltage with base open; defines safe operating range in flyback snubbers and ignition coil drivers.
I_C	300 mA continuous - Absolute max DC collector current; sets upper bound for sustained load switching in automotive body control modules.
h_FE	60–250 - DC current gain at V_CE = 5 V; enables predictable base drive sizing for 1–10 mA switching currents.
V_CE(sat)	150–250 mV at I_C = 50 mA / I_B = 5 mA - Low saturation voltage minimizes conduction loss in 12 V/24 V automotive relay drivers.
R_th(j-a)	500 K/W - Junction-to-ambient thermal resistance on standard FR4 PCB; determines required board copper area for thermal management.
f_T	100–300 MHz - Transition frequency at V_CE = 10 V, I_C = 10 mA; supports fast switching in pulse-width modulated HV bias supplies.
AEC-Q101	Qualified - Certified for automotive applications per Stress Test Qualification for Discrete Semiconductors; includes HTGB, HTRB, and ESD testing.

Pinout & Package

SOT23 plastic surface-mounted package: 3-terminal, 1.9 mm pitch, 2.9 mm × 1.3 mm × 1.0 mm body; optimized for reflow and wave soldering per Nexperia footprint guidelines (sot023_fr / sot023_fw).

Pin/Terminal	Circuit Role	Design Meaning
1	Base (B)	Control input node; requires current-limited drive (I_B ≤ 100 mA peak) to ensure safe saturation without overdrive.
2	Emitter (E)	Reference terminal for current sensing and grounding; connected directly to PCB ground plane for thermal and noise integrity.
3	Collector (C)	High-voltage output node; routed with clearance ≥ 0.8 mm to adjacent traces for 140 V working voltage compliance.

Key Features

Feature	Design Value
AEC-Q101 qualification	Validated for automotive underhood environments including HTGB (1500 h @ 150 °C), HTRB, and human-body-model ESD ≥ 2 kV.
High V_CEO rating	140 V enables direct interface with 24 V battery systems plus transient spikes up to ISO 7637-2 Pulse 1 (−150 V) when combined with external clamping.
Low V_CE(sat)	≤250 mV at I_C/I_B = 10 ensures <12.5 mW conduction loss at 50 mA load, critical for thermally constrained ECUs.
Controlled h_FE spread	Min 60 at I_C = 1 mA guarantees reliable turn-on with standard 10 kΩ pull-up/base resistors in discrete logic interfaces.
FR4-optimized thermal design	R_th(j-a) = 500 K/W measured on single-sided tin-plated FR4 allows thermal modeling without custom heatsinking in space-constrained modules.

Applications

Automotive Ignition Coil Driver

Industrial HV Bias Supply

Use Scenario: Switching 12 V–24 V battery supply to primary winding of distributorless ignition coils with 400 V flyback transients.

IC Role / Device Role / Timing Role: High-voltage NPN switch controlling coil energization timing; handles repetitive 140 V V_CEO stress during flyback recovery.

Use Value: AEC-Q101 qualification ensures reliability across −40 °C to +125 °C ambient; low V_CE(sat) reduces thermal load during 10–20 ms dwell periods.

Use Scenario: Providing regulated 100–120 V bias to photomultiplier tubes or avalanche photodiodes in analytical instrumentation.

IC Role / Device Role / Timing Role: Linear pass element in series-regulated HV supply; operated in active region with feedback-controlled base current.

Use Value: Tight h_FE min of 60 enables stable loop gain; low I_CBO (<50 nA) prevents drift in microamp-level bias current paths.

LED Streetlight Surge Protection

Telecom Line Interface

Use Scenario: Crowbar circuit triggered by MOV-clamped surges to short AC line during lightning-induced transients (>6 kV).

IC Role / Device Role / Timing Role: Fast-turn-on HV switch shunting surge energy to ground; activated by overvoltage detection network.

Use Value: f_T ≥ 100 MHz ensures sub-microsecond response; 600 mA I_CM withstands 8/20 µs surge peaks without second breakdown.

Use Scenario: Isolated ring generator interface in legacy PSTN line cards requiring ±90 V AC ringing signal generation.

IC Role / Device Role / Timing Role: High-voltage push-pull stage amplifying DC-biased AC waveform; biased in Class AB for low THD.

Use Value: V_CBO = 160 V exceeds 90 V RMS × √2 + margin; Ce = 30 pF minimizes capacitive loading on transformer-coupled output.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
BC847B-Q	V_CEO = 45 V, I_C = 100 mA, h_FE = 200–450 - lower voltage/current rating, higher gain spread.	Not suitable for >60 V applications; limited to low-side switching in 5–12 V logic interfaces.	Select only where V_CEO derating and thermal margin allow full replacement without redesign.
MMBT5551	V_CEO = 160 V, I_C = 600 mA, no AEC-Q101 qualification - higher voltage/current but unqualified for automotive use.	Acceptable in industrial HV switching where qualification is not mandated; requires external reliability validation.	Prefer for cost-sensitive non-automotive designs needing extra headroom; avoid in safety-critical vehicle subsystems.

Compared with BC847B-Q and MMBT5551, PMBT5550-QR uniquely balances 140 V capability, AEC-Q101 compliance, and SOT23 footprint-making it the only drop-in solution for automotive-grade HV switching where both voltage margin and qualification are mandatory.

Availability

PMBT5550-QR is available at Aetrix Electronics and suitable for automotive body control modules, industrial HV bias supplies, LED streetlight surge protection, and telecom line interface circuits requiring stable component supply and long-term lifecycle support.

Supply support for PMBT5550-QR 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 efficiency-driven analog, logic, and discrete components, with leadership in automotive-qualified small-signal transistors and ESD protection devices.

The PMBT5550-QR belongs to Nexperia's AEC-Q101-qualified high-voltage transistor family, engineered specifically for robust switching in automotive underhood and industrial high-reliability environments where voltage margin and thermal stability are critical.

FAQ

What is the maximum allowable junction temperature for PMBT5550-QR?

The absolute maximum junction temperature (T_j) is 150 °C, as specified in Table 5 of the datasheet. Operation above this limit risks permanent degradation of h_FE and increased leakage. Derating is required above T_amb = 25 °C using R_th(j-a) = 500 K/W on standard FR4 PCB.

Does PMBT5550-QR support pulsed operation beyond its DC current rating?

Yes - the peak collector current (I_CM) is rated at 600 mA for single pulses ≤1 ms, as defined in Table 5. This enables use in transient-heavy applications like ignition coil driving or surge crowbar circuits, provided duty cycle and thermal accumulation are verified.

How does the AEC-Q101 qualification apply to PMBT5550-QR?

AEC-Q101 qualification covers stress tests including high-temperature reverse bias (HTRB), high-temperature gate bias (HTGB), and human-body-model ESD (≥2 kV). It confirms suitability for automotive underhood use but does not imply functional safety certification (e.g., ISO 26262 ASIL).

Can PMBT5550-QR be used in linear (active) mode, not just switching?

Yes - its specified characteristics (h_FE, V_CE(sat), f_T, and thermal resistance) support linear operation, such as in HV current sources or analog bias generators. However, power dissipation must remain within P_tot = 250 mW at T_amb ≤ 25 °C, with appropriate derating.

PMBT5550-QR Specifications

Product attributes: Attribute value

Manufacturer:: Nexperia USA Inc.

Series:: -

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

Packaging:: Tape & Reel (TR)

Product Status:: Active

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 300 mA

Voltage - Collector Emitter Breakdown (Max):: 140 V

Vce Saturation (Max) @ Ib, Ic:: 250mV @ 5mA, 50mA

Current - Collector Cutoff (Max):: 50nA (ICBO)

DC Current Gain (hFE) (Min) @ Ic, Vce:: 60 @ 10mA, 5V

Power - Max:: 250 mW

Frequency - Transition:: 300MHz

Operating Temperature:: 150°C (TJ)

Grade:: Automotive

Qualification:: AEC-Q101

Mounting Type:: Surface Mount

Supplier Device Package:: TO-236AB

PMBT5550-QR FAQ

1.How can I place an order for PMBT5550-QR through Aetrix?

Please submit a Request for Quotation (RFQ) for PMBT5550-QR 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 PMBT5550-QR reliable?

The price and inventory of PMBT5550-QR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for PMBT5550-QR is usually 5 days.

3.What payment methods are accepted for PMBT5550-QR?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for PMBT5550-QR transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for PMBT5550-QR?

PMBT5550-QR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your PMBT5550-QR 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 PMBT5550-QR?

For technical support, including PMBT5550-QR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your PMBT5550-QR requirements.

6.How does Aetrix verify that PMBT5550-QR is sourced from the original manufacturer or authorized distributors?

All PMBT5550-QR 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 PMBT5550-QR meets industry standards.

7.What is the process for return or replacement of PMBT5550-QR?

All PMBT5550-QR units undergo pre-shipment inspection (PSI). If there is an issue with PMBT5550-QR, 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 PMBT5550-QR part is unused and in its original packaging.

Return procedure for PMBT5550-QR:

1.Submit a request within 90 days.

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

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