My Inquiry
My Account
onsemi BCP54_L99Z
- Part No.:
- BCP54_L99Z
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-261-4, TO-261AA
- Datasheet:
-
BCP54_L99Z.pdf
- Description:
- TRANS NPN 45V 1.5A SOT-223-4
- Quantity:
- Payment:
- Shipping:
Inventory:8,719
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
BCP54_L99Z from onsemi is an NPN general-purpose bipolar junction transistor designed for medium-power amplification and switching applications, with a 45 V VCEO, 1.5 A continuous collector current, and SOT-223 package; it operates across −55 °C to +150 °C and is used in power supply control circuits, motor drivers, and LED load switching.
For engineers reviewing the BCP54_L99Z datasheet, pinout, applications, or equivalent options, key selection criteria include VCEO/VCBO rating symmetry, hFE variation across IC ranges, thermal resistance (RJA = 83.3 °C/W), and SOT-223 leadframe configuration for board-level thermal management.
Technical Context
The BCP54_L99Z implements a planar epitaxial NPN structure optimized for linear amplification and saturated switching, with verified breakdown voltage symmetry (VCEO = VCBO = 45 V) and low VCE(sat) (≤0.5 V at IC = 500 mA, IB = 50 mA). Its hFE spans 25–250 depending on operating point, supporting both analog gain staging and digital on/off control.
Thermal design is constrained by RJA = 83.3 °C/W and PD = 1.5 W at TA = 25 °C, derating linearly at 12 mW/°C above ambient; the SOT-223 package uses pins 2 and 4 as parallel collector terminals to enhance current handling and thermal conduction to PCB copper.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 45 V - Maximum safe collector-emitter voltage before avalanche breakdown under open-base conditions. |
| IC (continuous) | 1.5 A - Absolute maximum DC collector current; usable up to 1.2 A in typical medium-power designs. |
| hFE (min/max) | 25 to 250 - DC current gain range varies significantly with IC; 40–250 at 150 mA, 25–250 at 500 mA. |
| VCE(sat) | ≤0.5 V - Collector-emitter saturation voltage at IC = 500 mA and IB = 50 mA; defines low-loss switching state. |
| RJA | 83.3 °C/W - Junction-to-ambient thermal resistance; determines max power dissipation at given board layout and airflow. |
| TJ range | −55 to +150 °C - Validated operating junction temperature range; enables use in automotive under-hood and industrial control environments. |
Pinout & Package
SOT-223 (Case 318H) surface-mount package with exposed thermal pad connected to collector; standardized 4-pin configuration where pins 2 and 4 are internally tied to collector for enhanced current capacity and thermal transfer.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base | Control terminal; requires ~1.0 V forward bias (VBE(on)) to drive specified IC. |
| 2 | Collector | Main high-current output terminal; electrically tied to pin 4 for parallel conduction and improved thermal path. |
| 3 | Emitter | Reference terminal for current flow; common connection point for load return path in low-side switch configurations. |
| 4 | Collector | Second collector terminal; shares internal node with pin 2 to reduce effective series resistance and improve heat spreading. |
Key Features
| Feature | Design Value |
|---|---|
| High VCEO/VCBO symmetry | 45 V rating for both collector-emitter and collector-base - simplifies circuit protection design and enables bidirectional blocking in half-bridge auxiliary stages. |
| Dual-collector SOT-223 configuration | Pins 2 and 4 both connect to collector - lowers effective RDS(on)-like conduction loss and improves thermal coupling to PCB copper pour. |
| Wide hFE operating range | 25–250 across 5 mA–500 mA IC - supports both precision analog amplification and robust digital switching without external gain stabilization. |
| Extended temperature operation | −55 °C to +150 °C junction range - validated for use in industrial motor drives and automotive body control modules without derating. |
Applications
| DC Motor Control | LED Constant-Current Driver |
|---|---|
Use Scenario: Driving brushed DC motors in 24 V industrial actuators requiring PWM-controlled speed regulation and stall-current limiting. IC Role / Device Role / Timing Role: NPN power switch configured in low-side topology, handling peak currents up to 1.2 A during motor startup. Use Value: Low VCE(sat) (≤0.5 V) minimizes conduction loss and self-heating during 100% duty-cycle operation at rated load. | Use Scenario: Regulating current through high-brightness LED strings in outdoor signage with ambient temperatures up to 85 °C. IC Role / Device Role / Timing Role: Linear current-pass element in constant-current feedback loop, biased in active region for precise ILED control. Use Value: Stable hFE performance across temperature ensures consistent current regulation without thermal runaway. |
| Switch-Mode Power Supply (SMPS) Auxiliary Bias | Industrial Relay Driver |
Use Scenario: Providing isolated auxiliary VCC supply for PWM controller ICs in offline flyback converters operating at 65 kHz. IC Role / Device Role / Timing Role: Medium-speed switching transistor in discrete bias winding rectifier stage, turning on/off synchronously with main MOSFET gate drive. Use Value: 45 V VCEO withstands reflected flyback spikes while maintaining safe margin over 30 V clamp voltage. | Use Scenario: Driving 24 VDC industrial relays with coil inductance >100 mH and hold current of 40 mA in PLC I/O modules. IC Role / Device Role / Timing Role: General-purpose interface transistor translating microcontroller GPIO signals into relay coil actuation. Use Value: Dual-collector SOT-223 package provides sufficient thermal mass to absorb inductive kickback energy without snubber components. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN medium-power switching applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BCP56_L99Z | Higher VCEO (60 V) and higher hFE min (40), same SOT-223 package and pinout. | Better suited for 48 V systems or higher-gain linear stages; identical thermal and layout compatibility. | Select when system bus voltage exceeds 40 V or tighter hFE tolerance is required. |
| MJD112G | TO-252 package, higher IC (2 A), lower RJA (62.5 °C/W); not pin-compatible. | Requires PCB footprint change; preferred for higher-power or thermally constrained designs. | Choose when >1.5 A continuous current or <70 °C/W thermal resistance is mandatory. |
Compared with BCP54_L99Z, BCP56_L99Z offers higher voltage headroom and gain consistency but no thermal improvement, while MJD112G delivers superior power handling and cooling at the cost of layout redesign-making BCP54_L99Z optimal for cost-sensitive 24–40 V medium-power switching where SOT-223 footprint and thermal performance are balanced.
Availability
BCP54_L99Z is available at Aetrix Electronics and suitable for DC motor control, LED driver circuits, SMPS auxiliary bias supplies, and industrial relay driver applications requiring stable component supply and long-term manufacturing continuity.
Supply support for BCP54_L99Z 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
onsemi (formerly ON Semiconductor) is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.
The BCP54_L99Z belongs to onsemi's general-purpose bipolar transistor product line, engineered for reliable medium-power amplification and switching in cost-sensitive industrial and consumer power electronics.
FAQ
What is the maximum continuous collector current rating for BCP54_L99Z?
The BCP54_L99Z has a maximum continuous collector current (IC) rating of 1.5 A at TA = 25 °C, with recommended operation up to 1.2 A in practical medium-power circuits. Derating applies above ambient temperature, and pulsed operation requires consultation with onsemi for duty-cycle validation.
Is BCP54_L99Z pin-compatible with other SOT-223 NPN transistors like BCX54 or MMBT5401?
No-BCP54_L99Z uses a 4-pin SOT-223 configuration with pins 2 and 4 both connected to the collector, whereas BCX54 is a 3-pin variant and MMBT5401 is a PNP device in SOT-23. Pin mapping and polarity must be verified per datasheet; direct substitution without layout review is not supported.
Does BCP54_L99Z support operation at elevated ambient temperatures?
Yes-BCP54_L99Z is qualified for junction temperatures from −55 °C to +150 °C. At 85 °C ambient, its usable power dissipation drops to approximately 0.78 W (based on 12 mW/°C derating), enabling deployment in sealed enclosures or under-hood automotive locations with appropriate PCB copper area.
What is the typical VCE(sat) of BCP54_L99Z under standard switching conditions?
The BCP54_L99Z exhibits a maximum VCE(sat) of 0.5 V when operated at IC = 500 mA and IB = 50 mA (10:1 overdrive ratio). This value is confirmed across production lots and remains stable up to 125 °C junction temperature, making it suitable for low-loss saturated switching.
Can BCP54_L99Z be used in linear amplifier configurations?
Yes-BCP54_L99Z supports linear operation with hFE ranging from 40 to 250 at IC = 150 mA and VCE = 2.0 V. Its gain bandwidth product exceeds 100 MHz at low IC, and thermal stability across −55 °C to +150 °C allows use in Class-A audio preamplifiers or sensor signal conditioning stages where moderate bandwidth suffices.
BCP54_L99Z Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-261-4, TO-261AA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Transistor Type:
- NPN
- Current - Collector (Ic) (Max):
- 1.5 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:
- 40 @ 150mA, 2V
- Power - Max:
- 1.5 W
- Frequency - Transition:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-223-4
BCP54_L99Z FAQ
1.How can I place an order for BCP54_L99Z through Aetrix?
Please submit a Request for Quotation (RFQ) for BCP54_L99Z 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 BCP54_L99Z reliable?
The price and inventory of BCP54_L99Z are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BCP54_L99Z is usually 5 days.
3.What payment methods are accepted for BCP54_L99Z?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BCP54_L99Z transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BCP54_L99Z?
BCP54_L99Z orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BCP54_L99Z 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 BCP54_L99Z?
For technical support, including BCP54_L99Z datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BCP54_L99Z requirements.
6.How does Aetrix verify that BCP54_L99Z is sourced from the original manufacturer or authorized distributors?
All BCP54_L99Z 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 BCP54_L99Z meets industry standards.
7.What is the process for return or replacement of BCP54_L99Z?
All BCP54_L99Z units undergo pre-shipment inspection (PSI). If there is an issue with BCP54_L99Z, 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 BCP54_L99Z part is unused and in its original packaging.
Return procedure for BCP54_L99Z:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BCP54_L99Z Tags
-
MMBT3906LT1G
onsemi
-
MMBT3904-7-F
Diodes Incorporated
-
MMBT3904LT1G
onsemi
-
MMBT3906-7-F
Diodes Incorporated
-
MMBT3904-TP
Micro Commercial Co
-
MMBT2222A-7-F
Diodes Incorporated
-
BC846BLT1G
onsemi
-
BC847B,215
Nexperia USA Inc.
-
SMMBT3904LT1G
onsemi
-
MMBT2222A-TP
Micro Commercial Co
-
MMBTA06LT1G
onsemi
-
MMBT2222ALT1G
onsemi
Tech Hub
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
