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onsemi BUD43B-001
- Part No.:
- BUD43B-001
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- -
- Datasheet:
-
BUD43B-001.pdf
- Description:
- SWITCHMODE NPN SILICON PLANAR PO
- Quantity:
- Payment:
- Shipping:
Inventory:57,675
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Product details
Overview
BUD43B-001 from onsemi is an NPN silicon planar power transistor optimized for 220 V line-operated switchmode power supplies and electronic ballasts. It features a 350 VCEO, 2 A continuous collector current, 25 W total device dissipation at TC = 25°C, VCE(sat) = 1 V (IC = 2 A, IB = 0.5 A), and fast switching with toff ≤ 5.8 μs - enabling high-efficiency, coil-free base drive in compact lighting and SMPS designs.
For engineers reviewing the BUD43B-001 datasheet, pinout, applications, or equivalent options, this page delivers verified electrical specs, DPAK package details, thermal resistance (RθJC = 5°C/W), switching timing under resistive load, and real-world use context for electronic ballast and offline SMPS design validation.
Technical Context
The BUD43B-001 employs a state-of-the-art die architecture specifically tuned for high-voltage switching applications, with flat DC current gain (hFE ≥ 6 at IC = 2 A) and tight distribution of switching parameters. Its low VBE(sat) (1.25 V max) and absence of current tail eliminate need for base coil, simplifying driver design.
It operates reliably across –65°C to +150°C junction temperature range and supports soldering at 260°C for 5 seconds at 1/8″ from case. Thermal performance is defined by RθJC = 5°C/W and RθJA = 71.4°C/W, confirming suitability for thermally constrained surface-mount implementations in enclosed ballast modules.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 350 Vdc - Sustains 220 V AC line-derived DC bus voltages with margin for transient spikes in SMPS and ballast topologies. |
| IC (cont.) | 2 Adc - Supports primary-side switching in sub-50 W electronic ballasts and auxiliary/standby SMPS stages. |
| VCE(sat) | 1 Vdc @ IC = 2 A, IB = 0.5 A - Minimizes conduction loss and self-heating during saturation, critical for thermal management in sealed fixtures. |
| toff | 5.8 μs max @ TC = 25°C - Enables >20 kHz switching in magnetic ballast replacement circuits without excessive switching loss. |
| RθJC | 5°C/W - Allows direct heatsinking to PCB copper or small metal clips, supporting compact DPAK-based thermal solutions. |
| fT | 13 MHz - Ensures adequate gain-bandwidth for stable base drive loop response in discrete transistor-based control schemes. |
| Cob | 40 pF @ VCB = 10 V - Low output capacitance reduces turn-off energy and improves efficiency in hard-switched flyback and resonant topologies. |
Pinout & Package
Package: DPAK (TO-252), Case 369−07 / 369A−13 - surface-mount, single-ended lead configuration with exposed drain pad for thermal conduction. Dimensions per ANSI Y14.5M: 6.35 mm × 6.73 mm × 2.38 mm (L × W × H), 3-pin layout.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Emitter) | Current return path for collector-emitter conduction | Connected to ground or low-side reference; requires low-inductance trace routing to minimize switching noise coupling. |
| 2 (Base) | Control input for transistor turn-on/turn-off | Driven directly from controller IC or resistor-limited source; no external coil needed due to fast intrinsic turn-off characteristics. |
| 3 (Collector) | Main high-voltage current path | Connected to primary winding of ballast transformer or SMPS inductor; electrically isolated from heatsink via PCB dielectric layer. |
Key Features
| Feature | Design Value |
|---|---|
| No base coil required | Eliminates external inductor in base circuit, reducing BOM count and board space in cost-sensitive ballast modules. |
| High and flat hFE | hFE ≥ 6 at IC = 2 A ensures consistent base drive requirements across production lots and temperature range. |
| Tightened switching distributions | Specified toff (4.7–5.8 μs) and tf (800 ns) enable predictable timing in discrete PWM control loops. |
| Low VCE(sat) | 1 V max at rated current reduces conduction loss to ≤2 W, easing thermal design in sealed plastic housings. |
| Robust voltage ratings | VCES = 650 Vdc allows safe operation under 380 V peak line conditions with safety margin for surge events. |
Applications
| Compact Fluorescent Lamp (CFL) Ballast | LED Driver Auxiliary Supply |
|---|---|
Use Scenario: High-frequency AC-to-DC conversion in integrated CFL retrofit lamps with <100 mm³ volume constraint. IC Role / Device Role / Timing Role: Primary-side switching transistor in half-bridge resonant inverter stage, operating at 30–50 kHz. Use Value: Fast toff and low Cob reduce switching losses, while DPAK package enables direct thermal coupling to aluminum housing. |
Use Scenario: Standby power supply in smart LED luminaires requiring <300 mW no-load consumption. IC Role / Device Role / Timing Role: Discrete switch in flyback converter delivering 12 V/100 mA for MCU and sensor subsystems. Use Value: VCEO = 350 V supports universal input (90–264 VAC), and 25 W PD rating accommodates short-term surge loads. |
| Industrial SMPS Auxiliary Winding Regulator | AC-DC Adapter Primary Switch |
Use Scenario: Regulation of auxiliary winding output in 200 W industrial SMPS where main controller IC derives bias from secondary side. IC Role / Device Role / Timing Role: Linear or switched regulator transistor controlling feedback to optocoupler LED, operating in linear or quasi-resonant mode. Use Value: Flat hFE ensures stable regulation across temperature; RθJC = 5°C/W permits mounting on shared heatsink with main power switch. |
Use Scenario: Cost-optimized 12 V/2 A wall adapter for consumer electronics using discrete topology. IC Role / Device Role / Timing Role: Primary-side switch in discontinuous conduction mode (DCM) flyback, driven by UC3842-class controller. Use Value: 2 A IC rating supports peak currents up to 4 A, and VCE(sat) = 1 V maintains efficiency >75% at full load. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN high-voltage switching transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| STN1NK60Z | 600 V VDSS, 1 A Id, MOSFET (not bipolar); gate-driven, no base current required. | Requires gate driver IC; lower conduction loss at light loads but higher gate charge limits switching speed vs. BUD43B-001. | Prefer when replacing aging BJT designs with MOSFET-based control for improved light-load efficiency. |
| MJD44H11T4G | NPN, 80 V VCEO, 8 A IC, TO-252 - lower voltage rating, higher current, same package. | Not suitable for 220 V line applications; limited to low-voltage DC-DC converters or motor drivers. | Select only for 24–48 V systems where higher current and lower VCE(sat) are prioritized over HV capability. |
Compared with STN1NK60Z and MJD44H11T4G, the BUD43B-001 uniquely balances 350 V blocking, 2 A current, and coil-free base drive - making it irreplaceable in legacy and cost-sensitive 220 V electronic ballast designs where MOSFET gate drive complexity or low-voltage limitations are unacceptable.
Availability
BUD43B-001 is available at Aetrix Electronics and suitable for compact fluorescent lamp (CFL) ballasts, LED driver auxiliary supplies, and industrial SMPS auxiliary winding regulators requiring stable component supply, long-lifecycle support, and DPAK-compatible thermal management.
Supply support for BUD43B-001 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 specializing in energy-efficient power, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.
The BUD43B-001 belongs to onsemi's SWITCHMODE™ planar power transistor family, engineered specifically for high-reliability, high-efficiency switching in 220 V line-powered lighting and power conversion equipment.
FAQ
What is the maximum junction temperature rating for the BUD43B-001?
The BUD43B-001 has a specified operating junction temperature range of –65°C to +150°C. This wide range supports deployment in thermally demanding environments such as enclosed electronic ballast housings and industrial power supplies where ambient temperatures may exceed 85°C. Derating begins above 25°C at 0.2 W/°C, ensuring safe operation within thermal limits when mounted on appropriate copper area.
Does the BUD43B-001 require a base drive coil for turn-off?
No, the BUD43B-001 does not require a base drive coil for fast turn-off. Its internal die design eliminates current tail and enables rapid, coil-free base discharge - a key feature confirmed in the original datasheet. This simplifies driver circuitry and reduces component count in BUD43B-001-based electronic ballast and SMPS designs.
What is the typical VCE(sat) of the BUD43B-001 under rated conditions?
The BUD43B-001 exhibits a maximum VCE(sat) of 1 Vdc when tested at IC = 2 Adc and IB = 0.5 Adc at TC = 25°C. Typical values are lower, contributing to reduced conduction loss and improved thermal performance in high-duty-cycle applications like continuous-operation CFL ballasts.
Can the BUD43B-001 be used in 230 V AC mains-powered applications?
Yes, the BUD43B-001 is explicitly designed for 220 V line-operated switchmode power supplies and electronic ballasts. With VCEO = 350 Vdc and VCES = 650 Vdc, it safely withstands peak rectified voltages (~325 V) and transient surges common in 230 V AC mains environments, meeting essential reliability requirements for BUD43B-001 deployments.
What package type is used for the BUD43B-001?
The BUD43B-001 uses the DPAK (TO-252) surface-mount package, designated as Case 369−07 / 369A−13. Its dimensions are 6.35 mm × 6.73 mm × 2.38 mm with three leads (Emitter, Base, Collector) and an exposed thermal pad - optimized for automated assembly and PCB-level thermal management in space-constrained lighting modules.
BUD43B-001 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- *
- Package/Case:
- -
- Packaging:
- Bulk
- Product Status:
- Active
- Transistor Type:
- -
- Current - Collector (Ic) (Max):
- -
- Voltage - Collector Emitter Breakdown (Max):
- -
- Vce Saturation (Max) @ Ib, Ic:
- -
- Current - Collector Cutoff (Max):
- -
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- -
- Power - Max:
- -
- Frequency - Transition:
- -
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- -
- Supplier Device Package:
- -
BUD43B-001 FAQ
1.How can I place an order for BUD43B-001 through Aetrix?
Please submit a Request for Quotation (RFQ) for BUD43B-001 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 BUD43B-001 reliable?
The price and inventory of BUD43B-001 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BUD43B-001 is usually 5 days.
3.What payment methods are accepted for BUD43B-001?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BUD43B-001 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BUD43B-001?
BUD43B-001 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BUD43B-001 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 BUD43B-001?
For technical support, including BUD43B-001 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BUD43B-001 requirements.
6.How does Aetrix verify that BUD43B-001 is sourced from the original manufacturer or authorized distributors?
All BUD43B-001 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 BUD43B-001 meets industry standards.
7.What is the process for return or replacement of BUD43B-001?
All BUD43B-001 units undergo pre-shipment inspection (PSI). If there is an issue with BUD43B-001, 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 BUD43B-001 part is unused and in its original packaging.
Return procedure for BUD43B-001:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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