BUL128D-B STMicroelectronics Transistor BJT NPN (Transistor Outline, Vertical) In Stock
BUL128D-B is an STMicroelectronics single NPN bipolar transistor with a built-in diode, housed in a 3-pin TO-220 package. It handles a 400V maximum collector-emitter voltage, 4A maximum collector current, and a minimum hFE of 12. In stock, worldwide shipping.
- Manufacturer
- STMicroelectronics
- Package
- Transistor Outline, Vertical
- Pin Count
- 3
- Lifecycle
- OBSOLETE
- Datasheet
- BUL128D-B Datasheet PDF
- Category
- Transistor BJT NPN
- Price
- From $0.3289(MOQ 1)
- Temp Range
- ?°C to 150.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
What are the key features of BUL128D-B?
- 400V maximum collector-emitter voltage for high-voltage switching
- 4A maximum collector current handling
- Minimum DC current gain (hFE) of 12
- Built-in diode for single-element NPN configuration
- Rugged 3-pin TO-220AB through-hole package
- Plastic/epoxy body construction for standard power-transistor assembly
What is BUL128D-B used for?
The BUL128D-B is well suited for high-voltage switching applications such as horizontal deflection circuits, industrial motor drivers, and switch-mode power supplies where a 400V blocking voltage is required. Its built-in diode simplifies flyback protection in inductive switching circuits, reducing external component count. The TO-220 package provides good thermal dissipation for 4A continuous current designs in power electronics.
What are the specifications of BUL128D-B?
| YTEOL | 0 |
| Collector Current-Max (IC) | 4A |
| Collector-Emitter Voltage-Max | 400V |
| Configuration | SINGLE WITH BUILT-IN DIODE |
| DC Current Gain-Min (hFE) | 12 |
| JEDEC-95 Code | TO-220AB |
| JESD-30 Code | R-PSFM-T3 |
| JESD-609 Code | e3 |
| Number of Elements | 1 |
| Package Body Material | PLASTIC/EPOXY |
| Package Shape | RECTANGULAR |
| Package Style | FLANGE MOUNT |
| Peak Reflow Temperature (Cel) | NOT SPECIFIED |
| Polarity/Channel Type | NPN |
| Power Dissipation Ambient-Max | 70W |
| Power Dissipation-Max (Abs) | 70W |
| Qualification Status | Not Qualified |
| Surface Mount | NO |
| Terminal Finish | Matte Tin (Sn) |
| Terminal Form | THROUGH-HOLE |
| Terminal Position | SINGLE |
| Time@Peak Reflow Temperature-Max (s) | NOT SPECIFIED |
| Transistor Application | SWITCHING |
| Transistor Element Material | SILICON |
| VCEsat-Max | 1.5V |
| Package | Transistor Outline, Vertical |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8541.29.00.95 |
| Country of Origin | Mainland China |
Where can I find the BUL128D-B datasheet?
BUL128D-B Datasheet DownloadOfficial datasheet from STMicroelectronics
What are equivalent replacements for BUL128D-B?
Compatible alternatives and drop-in replacements for BUL128D-B:
suggested
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Frequently Asked Questions
How much voltage can the BUL128D-B block?
The BUL128D-B has a maximum collector-emitter voltage of 400V and a maximum collector current of 4A, with a minimum DC current gain (hFE) of 12, making it suitable for high-voltage switching circuits.
How is the BUL128D-B packaged for power dissipation?
This NPN transistor is housed in a rugged 3-pin TO-220AB package with a plastic/epoxy body, providing good heat sinking for continuous currents up to 4A in switching power supply designs.
Why does the BUL128D-B include a built-in diode?
STMicroelectronics integrates a built-in diode into the single-element BUL128D-B to simplify flyback protection in inductive switching applications rated for a 400V collector-emitter voltage, reducing external component count on power boards.
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Why Buy from FindMyChip
About STMicroelectronics
STMicroelectronics is a global semiconductor leader serving customers across the spectrum of electronics applications. ST's products are found in a wide range of applications including automotive, industrial, personal electronics, and communications.
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 1+ | $0.4950 | $0.49 |
| 10+ | $0.4900 | $4.90 |
| 11+ | $0.4125 | $4.54 |
| 450+ | $0.4115 | $185.17 |
| 500+ | $0.3400 | $170.00 |
| 1000+ | $0.3289 | $328.88 |
In Stock · 24h Response · Worldwide Shipping
Response within 24 hours · Worldwide shipping
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