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STMicroelectronics BUW48
- Part No.:
- BUW48
- Manufacturer:
- STMicroelectronics
- Category:
- Single Bipolar Transistors
- Package:
- TO-218-3
- Datasheet:
-
BUW48.pdf
- Description:
- TRANS NPN 60V 30A TO-218-3
- Quantity:
- Payment:
- Shipping:
Inventory:6,043
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Product details
Overview
BUW48 from STMicroelectronics is a high-power NPN silicon transistor in TO-218 package, designed for switching regulators and motor control. It delivers 30 A continuous collector current, 120 V VCEV, 0.6 V VCE(sat) at IC = 20 A/IB = 2 A, and 8 MHz fT, enabling high-efficiency operation in industrial DC-DC converters.
For engineers reviewing the BUW48 datasheet, BUW48 pinout, BUW48 application, or BUW48 equivalent, key selection criteria include saturation voltage under high-current drive, thermal resistance (1 °C/W), switching speed (ton ≤ 1.5 µs), and ruggedness in inductive load switching.
Technical Context
The BUW48 employs multi-epitaxial planar construction to achieve low VCE(sat) and high gain at high current densities. Its rugged design supports pulsed operation with 45 A ICM and sustains 60 V VCEO(sus) under inductive switching with L = 25 mH.
Thermal performance is optimized via low Rthj-case (1 °C/W), allowing direct mounting to heatsinks for sustained 150 W dissipation at Tc = 25 °C. Switching behavior is characterized under defined resistive and inductive test conditions per ST's 2003 specification.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEV | 120 V - maximum safe collector-emitter voltage with reverse-biased base, critical for flyback and snubberless inductive switching |
| IC | 30 A - continuous collector current rating, defines steady-state power stage capacity in motor drivers |
| VCE(sat) | 0.6 V @ IC = 20 A, IB = 2 A - low conduction loss enabling >95% efficiency in 48 V industrial SMPS |
| fT | 8 MHz @ IC = 1 A, VCE = 15 V - usable for hard-switched topologies up to ~500 kHz with margin |
| Rthj-case | 1 °C/W - enables 150 W dissipation with ≤125 °C junction rise above case, simplifying thermal design |
| ton / tf | 1.5 µs / 0.25 µs - fast turn-on and fall times reduce switching losses in high-frequency converters |
Pinout & Package
TO-218 (SOT-93) plastic package with isolated metal tab; pin 1 = emitter, pin 2 = base, pin 3 = collector (tab-connected). Mounting hole Ø4.0–4.1 mm accommodates M3 screw.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Emitter) | Main current return path | Low-inductance connection point for high di/dt return paths in half-bridge output stages |
| 2 (Base) | Control input terminal | Requires 2 A DC drive for full saturation; base resistor design must support 12 A peak IBM for transient overloads |
| 3 (Collector / Tab) | High-current output node | Electrically connected to metal tab - must be insulated from heatsink unless common-collector topology is used |
Key Features
| Feature | Design Value |
|---|---|
| Multi-epitaxial planar structure | Enables uniform current distribution and stable β across 0–30 A range, reducing thermal runaway risk |
| Very low VCE(sat) | 0.6 V at rated 20 A ensures <12 W conduction loss, lowering heatsink requirements in 1–3 kW inverters |
| High ICM rating | 45 A peak collector current supports short-circuit robustness in motor phase-leg protection |
| Fast switching with low storage time | ts ≤ 1.1 µs minimizes charge recovery loss during commutation in PWM-driven H-bridges |
Applications
| Switching Regulators | Motor Control |
|---|---|
Use Scenario: 48 V input, 12 V/20 A output synchronous buck converter in industrial PLC power supply. IC Role / Device Role / Timing Role: Main switch in primary-side hard-switched topology, operating at 250 kHz with 50% duty cycle. Use Value: 0.6 V VCE(sat) limits conduction loss to 12 W, enabling compact heatsink design without forced air cooling. | Use Scenario: Phase-leg switch in 3-phase BLDC motor driver for HVAC compressors (1.5 kW). IC Role / Device Role / Timing Role: High-side NPN switch in totem-pole gate drive stage, commutated at 10–20 kHz. Use Value: 1.5 µs ton and 0.25 µs tf reduce switching energy per cycle, improving inverter efficiency by ~1.2% at full load. |
| High-Frequency Converters | Industrial Equipment |
Use Scenario: Resonant LLC auxiliary supply (380 V bus → 15 V/5 A) in telecom rectifier systems. IC Role / Device Role / Timing Role: Primary-side switching device in asymmetric half-bridge configuration. Use Value: 8 MHz fT ensures sufficient gain-margin for stable gate drive loop response up to 300 kHz fundamental frequency. | Use Scenario: Solenoid and valve driver in automated packaging machinery requiring 30 A pulsed actuation. IC Role / Device Role / Timing Role: Single-ended switch controlling 24 V inductive load with 100 ms on-time. Use Value: 45 A ICM and 175 °C Tj rating allow reliable 100% duty-cycle operation with minimal derating in enclosed cabinets. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar high-power NPN switching applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BUX87 | Higher VCEO (100 V) but higher VCE(sat) (1.2 V @ 20 A), lower fT (4 MHz) | Better for 80 V bus systems; less suitable for >200 kHz switching due to slower speed | Select when higher breakdown margin is prioritized over efficiency and frequency capability |
| BUW49 | Higher VCEV (160 V) and VCEO (80 V), but lower IC (30 A same), higher VCE(sat) (0.5 V typ. but 1.2 V max) | Preferred for 72–96 V industrial battery systems where voltage headroom outweighs conduction loss | Choose BUW49 only if system bus voltage exceeds 65 V; otherwise BUW48 offers superior efficiency |
Compared with BUW49 and BUX87, BUW48 provides the lowest VCE(sat) and highest fT among ST's legacy TO-218 NPNs, making it optimal for efficiency-critical, medium-voltage (<65 V) high-frequency switching where thermal management is constrained.
Availability
BUW48 is available at Aetrix Electronics and suitable for switching regulators, motor control, and high-frequency converters requiring stable component supply in industrial OEM production.
Supply support for BUW48 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
STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer markets.
The BUW48 belongs to ST's legacy high-power bipolar transistor product line, engineered specifically for rugged, high-current switching in industrial power conversion and motion control equipment.
FAQ
Is BUW48 still in active production?
No - BUW48 is marked "Obsolete Product(s)" in ST's official 2003 datasheet. Aetrix Electronics supplies remaining factory-new stock with full traceability and supports legacy design continuity through controlled allocation and cross-reference guidance.
What is the maximum safe operating temperature for BUW48?
The BUW48 has a maximum junction temperature (Tj) of 175 °C and storage temperature range of –65 to +175 °C. For reliable long-term operation, keep Tj ≤ 150 °C using the specified 1 °C/W Rthj-case and appropriate heatsinking.
Can BUW48 be used in avalanche mode?
No - BUW48 is not rated for repetitive avalanche operation. Its VCEO(sus) = 60 V is measured under specific inductive switching conditions (L = 25 mH), but no energy-rated avalanche SOA is provided in the datasheet.
What base drive current is required for full saturation?
For guaranteed VCE(sat) ≤ 0.6 V, apply IB = 2 A DC with IC = 20 A. Peak base current up to 12 A (IBM) is allowed for <5 ms pulses, supporting transient overload conditions in motor startup or fault recovery.
BUW48 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- TO-218-3
- Packaging:
- Tube
- Product Status:
- Obsolete
- Transistor Type:
- NPN
- Current - Collector (Ic) (Max):
- 30 A
- Voltage - Collector Emitter Breakdown (Max):
- 60 V
- Vce Saturation (Max) @ Ib, Ic:
- 1.4V @ 4A, 40A
- Current - Collector Cutoff (Max):
- -
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- -
- Power - Max:
- 150 W
- Frequency - Transition:
- 8MHz
- Operating Temperature:
- 175°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-218-3
BUW48 FAQ
1.How can I place an order for BUW48 through Aetrix?
Please submit a Request for Quotation (RFQ) for BUW48 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 BUW48 reliable?
The price and inventory of BUW48 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BUW48 is usually 5 days.
3.What payment methods are accepted for BUW48?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BUW48 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BUW48?
BUW48 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BUW48 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 BUW48?
For technical support, including BUW48 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BUW48 requirements.
6.How does Aetrix verify that BUW48 is sourced from the original manufacturer or authorized distributors?
All BUW48 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 BUW48 meets industry standards.
7.What is the process for return or replacement of BUW48?
All BUW48 units undergo pre-shipment inspection (PSI). If there is an issue with BUW48, 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 BUW48 part is unused and in its original packaging.
Return procedure for BUW48:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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