STB85NF55T4 STMicroelectronics MOSFET (N-Channel) (Surface Mount D2PAK (TO-263)) In Stock
STB85NF55T4 is a high-current N-channel power MOSFET by STMicroelectronics rated at 55 V and 80 A with an ultra-low 8 mΩ on-resistance. Key specs: 980 mJ avalanche energy rating, drain-connected case in TO-263AB package. From competitive pricing, in stock with worldwide shipping.
- Manufacturer
- STMicroelectronics
- Package
- Surface Mount D2PAK (TO-263)
- Pin Count
- 4
- Lifecycle
- ACTIVE
- Datasheet
- STB85NF55T4 Datasheet PDF
- Category
- MOSFET (N-Channel)
- Price
- From $0.8910(MOQ 10)
- Temp Range
- ?°C to 175.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- Ultra-low 8 mΩ maximum drain-source on-resistance (RDS(on)) minimizing conduction losses in high-current paths
- 80 A continuous drain current capability with 55 V breakdown voltage for high-power switching applications
- Robust 980 mJ avalanche energy rating (EAS) providing exceptional protection against inductive voltage transients
- TO-263AB (D2PAK) surface-mount package offering compact PCB footprint with excellent thermal performance
Applications
The STB85NF55T4 is designed for high-current DC-DC converters, synchronous rectification, motor drive circuits, and battery management systems operating at voltages up to 55 V. Its ultra-low RDS(on) of 8 mΩ makes it highly effective in automotive power stages, point-of-load converters, and UPS systems where conduction losses must be minimized. The high avalanche energy rating ensures reliable operation in inductive load switching and systems subject to voltage transients.
Specifications
| Factory Lead Time | 13Weeks |
| YTEOL | 5.6 |
| Avalanche Energy Rating (Eas) | 980mJ |
| Case Connection | DRAIN |
| Configuration | SINGLE WITH BUILT-IN DIODE |
| DS Breakdown Voltage-Min | 55V |
| Drain Current-Max (ID) | 80A |
| Drain-source On Resistance-Max | 0.008Ω |
| FET Technology | METAL-OXIDE SEMICONDUCTOR |
| JEDEC-95 Code | TO-263AB |
| JESD-30 Code | R-PSSO-G2 |
| JESD-609 Code | e3 |
| Number of Elements | 1 |
| Operating Mode | ENHANCEMENT MODE |
| Package Body Material | PLASTIC/EPOXY |
| Package Shape | RECTANGULAR |
| Package Style | SMALL OUTLINE |
| Peak Reflow Temperature (Cel) | 245 |
| Polarity/Channel Type | N-CHANNEL |
| Power Dissipation-Max (Abs) | 300W |
| Pulsed Drain Current-Max (IDM) | 320A |
| Qualification Status | Not Qualified |
| Surface Mount | YES |
| Terminal Finish | Matte Tin (Sn) |
| Terminal Form | GULL WING |
| Terminal Position | SINGLE |
| Time@Peak Reflow Temperature-Max (s) | 30 |
| Transistor Application | SWITCHING |
| Transistor Element Material | SILICON |
| Package | Surface Mount D2PAK (TO-263) |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| Moisture Sensitivity Level | MSL 1 |
| ECCN | EAR99 |
| Country of Origin | Mainland China |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for STB85NF55T4:
Power Field-Effect Transistor, 80A I(D), 55V, 0.01ohm, 1-Element, N-Channel, Silicon, Metal-oxide Semiconductor FET, TO-263AB
Frequently Asked Questions
What is the maximum drain current and voltage of the STB85NF55T4?
The STB85NF55T4 supports a maximum continuous drain current (ID) of 80 A and a drain-source breakdown voltage of 55 V minimum. These specifications make it well-suited for high-current, low-voltage power conversion applications such as synchronous buck converters and motor controllers.
What is the RDS(on) of the STB85NF55T4 and how does it benefit power efficiency?
The STB85NF55T4 has an ultra-low maximum RDS(on) of 8 mΩ (0.008 Ω). This extremely low on-resistance significantly reduces conduction power losses (P = I²R), enabling high-efficiency power conversion at elevated currents, which is critical in motor drives, battery chargers, and DC-DC converters.
What package is the STB85NF55T4 available in and what are its thermal benefits?
The STB85NF55T4 is housed in a TO-263AB (D2PAK) surface-mount package with the drain connected to the case. This package provides an excellent thermal path to the PCB, allowing effective heat dissipation through copper pours or heatsinking without through-hole mounting, making it ideal for automated SMT assembly.
What is the avalanche energy rating of the STB85NF55T4 and why is it important?
The STB85NF55T4 has an avalanche energy rating (EAS) of 980 mJ, one of the highest in its class. This robust avalanche capability protects the device during unclamped inductive switching events, such as when driving motors or solenoids, ensuring long-term reliability even under demanding transient conditions.
What are typical applications for the STB85NF55T4?
The STB85NF55T4 is commonly used in automotive power modules, industrial motor drives, synchronous rectification stages, battery management systems (BMS), and high-current DC-DC converters. Its combination of low RDS(on), high current capability, and robust avalanche rating makes it particularly suited to harsh and high-power environments.
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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 |
|---|---|---|
| 10+ | $2.2270 | $22.27 |
| 100+ | $1.5447 | $154.47 |
| 125+ | $1.3500 | $168.75 |
| 400+ | $1.0125 | $405.00 |
| 1000+ | $0.8910 | $891.00 |
In Stock · 24h Response · Worldwide Shipping
Response within 24 hours · Worldwide shipping
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