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Nexperia USA Inc. BCP51-QX
- Part No.:
- BCP51-QX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- TO-261-4, TO-261AA
- Datasheet:
-
BCP51-QX.pdf
- Description:
- TRANS PNP 45V 1A SOT-223
- Quantity:
- Payment:
- Shipping:
Inventory:1,000
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Product details
Overview
BCP51-Q from Nexperia is a PNP medium-power bipolar junction transistor in SOT223 (SC-73) package, rated for −45 V VCEO, −1 A continuous collector current, and 1.35 W power dissipation with 6 cm² copper pad. It delivers hFE = 63–250 at IC = −150 mA and is AEC-Q101 qualified for automotive linear voltage regulators and high-side switches.
For engineers reviewing the BCP51-Q datasheet, BCP51-Q pinout, BCP51-Q application, or BCP51-Q equivalent, this device is selected for stable high-current PNP switching in thermally constrained PCB layouts where junction-to-ambient thermal resistance must be ≤93 K/W and DC gain consistency across −55 °C to +150 °C is required.
Technical Context
This PNP transistor operates in active, saturation, and cutoff regions with VBE ≈ −1 V at IC = −500 mA and VCE(sat) ≤ −0.5 V at IC/IB = 10. Its fT = 145 MHz enables use in low-noise amplification up to mid-RF frequencies.
Thermal performance depends on PCB copper area: Rth(j-a) ranges from 93 K/W (6 cm² pad) to 192 K/W (standard footprint), and transient thermal impedance shows strong pulse-duration dependence below 1 ms per Fig. 2–4.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | −45 V - maximum safe collector-emitter voltage with base open; defines high-side switch blocking capability |
| IC | −1 A - continuous DC collector current rating; supports 1 A load switching in battery-driven devices |
| Ptot | 1.35 W - max power dissipation with 6 cm² copper pad; sets thermal design margin for linear regulator pass elements |
| hFE | 63–250 - DC current gain range at VCE = −2 V, IC = −150 mA; ensures predictable base drive sizing |
| fT | 145 MHz - transition frequency at VCE = −5 V, IC = −50 mA; supports broadband amplifier stages |
| Rth(j-a) | 93 K/W - junction-to-ambient thermal resistance with 6 cm² copper; determines steady-state temperature rise under full load |
| VCE(sat) | ≤ −0.5 V - collector-emitter saturation voltage at IC = −500 mA, IB = −50 mA; minimizes conduction loss in switching applications |
Pinout & Package
SOT223 (SC-73) surface-mount plastic package with 4 leads, 2.3 mm pitch, and 6.5 mm × 3.5 mm × 1.65 mm body dimensions. Collector terminals are internally paralleled on pins 2 and 4 for enhanced thermal and current handling.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base | Control input requiring −50 mA base drive for full saturation at −500 mA collector current |
| 2 | Collector | Main high-current output path; electrically tied to pin 4 for dual-terminal current sharing |
| 3 | Emiter | Reference terminal connected to system ground or positive rail in high-side configuration |
| 4 | Collector | Redundant collector connection; improves thermal conduction and reduces effective RDS(on)-like resistance |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive underhood environments with guaranteed operation from −55 °C to +150 °C junction temperature |
| Three hFE bins | BCP51-Q (63–250), BCP51-10-Q (63–160), BCP51-16-Q (100–250) - enables precise gain matching in feedback loops |
| Dual-collector thermal design | Pins 2 and 4 both connect to collector, lowering thermal resistance by ~15% versus single-pin SOT223 variants |
| High peak current rating | ICM = −2 A (1 ms pulse) - supports surge handling in power management during load transients |
Applications
| Linear Voltage Regulators | High-Side Switches |
|---|---|
Use Scenario: Adjustable 3.3 V/5 V linear regulator using external pass transistor and error amplifier. IC Role / Device Role / Timing Role: PNP pass element controlling output voltage via emitter-follower configuration with base driven by op-amp. Use Value: Low VCE(sat) (≤ −0.5 V) minimizes dropout voltage; 1.35 W dissipation supports ≥1 A output at <10 °C/W heatsink-equivalent PCB layout. | Use Scenario: 12 V automotive load switch controlling solenoid or relay coil. IC Role / Device Role / Timing Role: High-side PNP switch with base resistor network enabling ON/OFF control from microcontroller GPIO. Use Value: −45 V VCEO withstands load-dump transients; AEC-Q101 qualification ensures reliability in 12 V vehicle electrical systems. |
| Battery-Driven Devices | MOSFET Drivers |
Use Scenario: Reverse-polarity protection and load switching in portable medical monitors powered by Li-ion packs. IC Role / Device Role / Timing Role: PNP configured as reverse-voltage blocking switch upstream of main power rail. Use Value: −5 V VEBO rating allows safe operation with ±5 % battery tolerance; low ICBO (≤ −100 nA) preserves standby current budget. | Use Scenario: Level-shifting driver stage translating 3.3 V logic to −12 V gate control for N-channel high-side MOSFETs. IC Role / Device Role / Timing Role: PNP-based totem-pole or complementary emitter-follower providing fast turn-off current sink. Use Value: fT = 145 MHz enables <100 ns switching transitions; dual-collector layout sustains 500 mA peak sink current without thermal throttling. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP medium-power transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BCP52-Q | −60 V VCEO, same SOT223 package and AEC-Q101 qualification | Higher voltage blocking; suitable for 24 V industrial systems but higher VCE(sat) (−0.6 V) | Select when >45 V transient immunity is required and 0.1 V higher saturation drop is acceptable |
| ZTX951 | −60 V VCEO, TO-92 package, hFE = 100–800, no AEC-Q101 | Through-hole mounting only; wider gain spread; not automotive-qualified | Choose only for non-automotive prototyping or legacy through-hole designs where thermal derating is less critical |
Compared with BCP52-Q and ZTX951, the BCP51-Q offers optimal balance of −45 V rating, 1.35 W thermal capability, and AEC-Q101 compliance in SOT223 - making it preferred for cost-sensitive, space-constrained automotive linear regulators and high-side switches where exact voltage margin and surface-mount assembly are mandatory.
Availability
BCP51-Q is available at Aetrix Electronics and suitable for linear voltage regulators, high-side switches, and battery-driven devices requiring stable component supply with automotive-grade reliability and SOT223 thermal performance.
Supply support for BCP51-Q 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 technologies, delivering high-performance, reliable discrete and logic devices for automotive, industrial, and consumer markets.
The BCP51-Q belongs to Nexperia's AEC-Q101-qualified medium-power bipolar transistor product line, engineered specifically for robust linear regulation and high-side switching in thermally demanding automotive and industrial power systems.
FAQ
What is the maximum allowable junction temperature for continuous operation?
The BCP51-Q has a maximum junction temperature (Tj) of 150 °C per IEC 60134 limiting values. Operation above this threshold risks permanent degradation. Derating is required above 25 °C ambient: for example, at 100 °C ambient, maximum usable power drops to ~0.7 W when mounted on a 6 cm² copper pad, based on the 93 K/W Rth(j-a) curve.
How does the dual-collector pin configuration affect PCB layout?
Pins 2 and 4 are internally shorted to the collector, allowing either or both to be used for routing. This configuration lowers effective thermal resistance by distributing heat across two solder joints and enables flexible layout-such as placing one collector pad near a thermal plane and the other near a current-carrying trace-without sacrificing current capacity or thermal performance.
Is the BCP51-Q suitable for use in Class D amplifier output stages?
No. While its fT = 145 MHz supports RF amplification, the BCP51-Q lacks the fast switching characteristics (e.g., low storage time, optimized charge removal) and SOA robustness required for Class D output switching. It is designed for linear regulation and moderate-speed switching-not high-frequency PWM with reactive loads.
Can the BCP51-Q replace the older BCP51 in existing designs?
Yes, the BCP51-Q is a direct replacement for the legacy BCP51 with identical pinout, package, and electrical specifications-but adds AEC-Q101 qualification and tighter hFE binning (63–250 vs. original 40–250). No layout or schematic changes are needed; however, designers should verify that the new gain range meets closed-loop stability requirements in feedback-dependent circuits.
BCP51-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:
- PNP
- Current - Collector (Ic) (Max):
- 1 A
- Voltage - Collector Emitter Breakdown (Max):
- 45 V
- Vce Saturation (Max) @ Ib, Ic:
- 500mV @ 50mA, 500mA
- Current - Collector Cutoff (Max):
- 100nA (ICBO)
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 63 @ 150mA, 2V
- Power - Max:
- 650 mW
- Frequency - Transition:
- 145MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q100
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-223
BCP51-QX FAQ
1.How can I place an order for BCP51-QX through Aetrix?
Please submit a Request for Quotation (RFQ) for BCP51-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 BCP51-QX reliable?
The price and inventory of BCP51-QX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BCP51-QX is usually 5 days.
3.What payment methods are accepted for BCP51-QX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BCP51-QX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BCP51-QX?
BCP51-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BCP51-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 BCP51-QX?
For technical support, including BCP51-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BCP51-QX requirements.
6.How does Aetrix verify that BCP51-QX is sourced from the original manufacturer or authorized distributors?
All BCP51-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 BCP51-QX meets industry standards.
7.What is the process for return or replacement of BCP51-QX?
All BCP51-QX units undergo pre-shipment inspection (PSI). If there is an issue with BCP51-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 BCP51-QX part is unused and in its original packaging.
Return procedure for BCP51-QX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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