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Nexperia USA Inc. BSP51-QX
- Part No.:
- BSP51-QX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- TO-261-4, TO-261AA
- Datasheet:
-
BSP51-QX.pdf
- Description:
- TRANS NPN DARL 60V 1A SOT-223
- Quantity:
- Payment:
- Shipping:
Inventory:6,754
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Product details
Overview
BSP51-QX from Nexperia is an AEC-Q101-qualified NPN Darlington transistor in SOT223 (SC-73) package, delivering 1 A continuous collector current, 60 V VCES, and DC current gain (hFE) ≥1000 at IC = 150 mA. It integrates base-emitter clamping diode and base resistor, enabling direct microcontroller drive in automotive load switching applications.
For engineers reviewing the BSP51-QX datasheet, BSP51-QX pinout, BSP51-QX application, or BSP51-QX equivalent, key selection criteria include its qualified automotive reliability, thermal resistance (Rth(j-sp) = 17 K/W), saturation voltage (VCE(sat) ≤ 1.3 V at 500 mA), and dual-collector SOT223 layout for enhanced power dissipation.
Technical Context
This Darlington pair uses monolithic integration of two NPN transistors with built-in base resistor and emitter-clamp diode, eliminating external bias components. Its structure supports high DC gain while maintaining low saturation voltage under high-current switching conditions.
Designed for automotive-grade robustness, it operates across −65 °C to +150 °C ambient, with junction temperature limited to 150 °C and qualified per AEC-Q101 stress tests including HTGB, HTRB, and ESD-HBM ≥8 kV. Thermal performance relies on solder-point conduction via the extended collector pad.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCES | 60 V - Maximum safe collector-emitter voltage with base shorted to emitter; defines maximum load supply rail compatibility. |
| IC | 1 A - Continuous collector current rating; enables direct driving of solenoids, relays, and LED arrays without external heatsinking at moderate duty cycles. |
| hFE | ≥1000 @ VCE = 10 V, IC = 150 mA - High DC gain reduces required base drive current, allowing direct interface with 3.3 V/5 V GPIOs. |
| VCE(sat) | ≤1.3 V @ IC = 500 mA, IB = 0.5 mA - Low saturation voltage minimizes power loss and self-heating during on-state operation. |
| Rth(j-sp) | 17 K/W - Junction-to-solder-point thermal resistance; enables predictable thermal design when mounted on 1 cm² copper pad per JEDEC standard. |
| toff | ≤1300 ns - Turn-off time under specified test conditions; suitable for PWM frequencies up to ~100 kHz in non-critical timing applications. |
| VEBO | 5 V - Maximum reverse emitter-base voltage; constrains allowable negative base drive or transient clamping requirements. |
Pinout & Package
Package: SC-73 (SOT223) - surface-mount plastic package with 4 leads, 2.3 mm pitch, 6.5 mm × 3.5 mm × 1.65 mm body, and integrated heatsink pad on lead 2 and 4 (both collectors).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base (B) | Control input node; internally connected to base of first transistor and series resistor; accepts logic-level drive. |
| 2 | Collector (C) | Main power output terminal; electrically tied to pin 4; forms primary thermal path to PCB copper. |
| 3 | Emitter (E) | Common emitter node; referenced to system ground or load return; carries full load current. |
| 4 | Collector (C) | Duplicate collector connection; improves current sharing and thermal conduction; must be soldered to same net as pin 2. |
Key Features
| Feature | Design Value |
|---|---|
| Integrated base resistor | Enables single-pin digital control without external bias network; simplifies PCB layout and reduces BOM count. |
| AEC-Q101 qualification | Validated for automotive under-hood and cabin applications including engine control modules and body electronics. |
| Dual-collector thermal design | Two collector pins (2 & 4) share current and conduct heat directly to PCB, supporting 1.25 W total power dissipation at Tamb ≤ 25 °C. |
| Clamped emitter-base junction | Internal diode prevents reverse-bias damage during inductive load flyback, reducing need for external snubbers. |
Applications
| Automotive Door Lock Actuation | Industrial PLC Output Stage |
|---|---|
|
Use Scenario: Driving 12 V DC solenoid locks in vehicle door modules with microcontroller GPIO control. IC Role / Device Role / Timing Role: High-gain switch amplifying low-current MCU output to deliver 800 mA lock coil current. Use Value: Eliminates need for discrete base resistor and flyback diode; AEC-Q101 qualification ensures field reliability over 15-year vehicle lifetime. |
Use Scenario: Switching 24 V industrial indicator lamps and small relays in programmable logic controller output cards. IC Role / Device Role / Timing Role: Final-stage power switch interfacing between isolation barrier and load; handles repetitive on/off cycling. Use Value: 1.3 V VCE(sat) limits power loss to <1 W at full load, avoiding forced-air cooling in compact DIN-rail enclosures. |
| Motorized HVAC Damper Control | Commercial Lighting Dimming Interface |
|
Use Scenario: Controlling bidirectional 24 V DC damper motors in building automation systems using PWM-driven H-bridge half-bridge sections. IC Role / Device Role / Timing Role: High-side or low-side switch in discrete H-bridge; withstands inductive kickback during direction reversal. Use Value: Integrated emitter-clamp diode suppresses >5 V reverse transients, preventing latch-up during motor commutation. |
Use Scenario: Enabling/disabling 0–10 V dimming circuits or DALI slave drivers in commercial LED fixtures. IC Role / Device Role / Timing Role: Logic-level controlled enable switch isolating dimming reference voltage from downstream ICs. Use Value: hFE ≥1000 ensures stable turn-on with <100 µA base current, compatible with ultra-low-power microcontrollers. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN Darlington switching applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ZTX1048A | Higher VCES (80 V), lower hFE (500 min), TO-92 package, no integrated resistor or diode. | Requires external base resistor and flyback diode; unsuitable for space-constrained automotive PCBs. | Select only if higher breakdown voltage is critical and board area allows discrete support components. |
| BSP52-Q | PNP complement; identical package, thermal specs, and AEC-Q101 qualification; VECS = 60 V, IC = −1 A. | Used in high-side or complementary switching configurations where sourcing current is required. | Choose for complementary designs requiring matched thermal and qualification profiles in same footprint. |
Compared with ZTX1048A and BSP52-Q, the BSP51-QX provides integrated biasing and clamping in an automotive-qualified SOT223 package-reducing component count and validation effort for 12/24 V load switching, while BSP52-Q serves as a functionally symmetric PNP counterpart for full-bridge topologies.
Availability
BSP51-QX is available at Aetrix Electronics and suitable for automotive body control modules, industrial PLC output stages, and commercial HVAC actuator drives requiring stable component supply and long-term lifecycle assurance.
Supply support for BSP51-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 essential efficiency-enhancing components, with leadership in logic, discrete, and MOSFET technologies for automotive, industrial, and consumer markets.
The BSP51-QX belongs to Nexperia's AEC-Q101-qualified bipolar transistor portfolio, engineered specifically for robust, high-gain switching in harsh-environment automotive and industrial control systems.
FAQ
Is BSP51-QX pin-compatible with BSP51?
Yes - BSP51-QX is the qualified automotive variant of BSP51, sharing identical pinout (SC-73), electrical specifications, and mechanical dimensions. The "-QX" suffix denotes AEC-Q101 qualification and enhanced traceability; no layout or schematic changes are needed for migration.
Can BSP51-QX replace a standard NPN transistor like BC817 in existing designs?
No - BSP51-QX is a Darlington with integrated resistor and diode, exhibiting higher VCE(sat) (1.3 V vs. ~0.2 V), slower switching (toff ≤1300 ns), and fixed gain architecture. Direct substitution would increase power loss and degrade PWM response; redesign of base drive and thermal layout is required.
What is the maximum PCB copper area needed to sustain 1 A continuous current?
Per Nexperia's thermal characterization, a 1 cm² single-sided FR4 copper pad (tin-plated) under the collector leads achieves Rth(j-a) = 96 K/W. To sustain 1 A continuously at 25 °C ambient without exceeding Tj = 150 °C, that pad is sufficient - but derating is required above 25 °C or with reduced airflow.
Does BSP51-QX require an external flyback diode when driving inductive loads?
No - the device integrates an emitter-base clamping diode rated for 5 V reverse breakdown, which safely clamps inductive flyback transients below damaging levels. External diodes are unnecessary unless peak transient energy exceeds device capability (e.g., >2 A × 60 V × 1 µs).
BSP51-QX Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- -
- Package/Case:
- TO-261-4, TO-261AA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Transistor Type:
- NPN - Darlington
- Current - Collector (Ic) (Max):
- 1 A
- Voltage - Collector Emitter Breakdown (Max):
- 60 V
- Vce Saturation (Max) @ Ib, Ic:
- 1.3V @ 500µA, 500mA
- Current - Collector Cutoff (Max):
- 50nA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 2000 @ 500mA, 10V
- Power - Max:
- 1.25 W
- Frequency - Transition:
- 200MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-223
BSP51-QX FAQ
1.How can I place an order for BSP51-QX through Aetrix?
Please submit a Request for Quotation (RFQ) for BSP51-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 BSP51-QX reliable?
The price and inventory of BSP51-QX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BSP51-QX is usually 5 days.
3.What payment methods are accepted for BSP51-QX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BSP51-QX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BSP51-QX?
BSP51-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BSP51-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 BSP51-QX?
For technical support, including BSP51-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BSP51-QX requirements.
6.How does Aetrix verify that BSP51-QX is sourced from the original manufacturer or authorized distributors?
All BSP51-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 BSP51-QX meets industry standards.
7.What is the process for return or replacement of BSP51-QX?
All BSP51-QX units undergo pre-shipment inspection (PSI). If there is an issue with BSP51-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 BSP51-QX part is unused and in its original packaging.
Return procedure for BSP51-QX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BSP51-QX Tags
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