STU70R1K3S STMicroelectronics MOSFET (N-Channel) (Transistor Outline, Vertical) In Stock
STMicroelectronics STU70R1K3S is an N-channel 700 V, 5 A power MOSFET with 1.3 Ω typical on-resistance and 90 mJ avalanche energy rating, housed in an IPAK package for efficient high-voltage switching in power conversion circuits.
- Manufacturer
- STMicroelectronics
- Package
- Transistor Outline, Vertical
- Pin Count
- 3
- Lifecycle
- OBSOLETE
- Datasheet
- STU70R1K3S Datasheet PDF
- Category
- MOSFET (N-Channel)
- Temp Range
- -55.0°C to 150.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- 700 V drain-source breakdown voltage enabling direct operation from rectified mains in 230 VAC offline power supplies
- 1.3 Ω typical on-resistance at 5 A drain current reducing conduction losses in switching converters
- 90 mJ avalanche energy (Eas) rating providing robust unclamped inductive switching (UIS) protection
- Built-in body diode configuration in compact IPAK package suitable for space-efficient PCB layouts
Applications
The STU70R1K3S is well-suited for offline flyback and forward converters, PFC stages, and resonant converter topologies operating from 85 VAC to 264 VAC mains input where a 700 V MOSFET is required. Its 1.3 Ω on-resistance and 5 A continuous drain current support power levels up to approximately 30 W to 50 W in compact switching power supplies for LED drivers, consumer adapters, and industrial auxiliary supplies. The 90 mJ avalanche energy rating and IPAK through-hole package make it reliable in environments with inductive load switching transients such as motor drive auxiliary rails and SMPS with imperfect snubbers.
Specifications
| Date Of Intro | 2020-09-03 |
| YTEOL | 0 |
| Avalanche Energy Rating (Eas) | 90mJ |
| Case Connection | DRAIN |
| Configuration | SINGLE WITH BUILT-IN DIODE |
| DS Breakdown Voltage-Min | 700V |
| Drain Current-Max (ID) | 5A |
| Drain-source On Resistance-Max | 1.4Ω |
| FET Technology | METAL-OXIDE SEMICONDUCTOR |
| Feedback Cap-Max (Crss) | 0.43pF |
| JEDEC-95 Code | TO-251 |
| JESD-30 Code | R-PSIP-T3 |
| Number of Elements | 1 |
| Operating Mode | ENHANCEMENT MODE |
| Package Body Material | PLASTIC/EPOXY |
| Package Shape | RECTANGULAR |
| Package Style | IN-LINE |
| Polarity/Channel Type | N-CHANNEL |
| Power Dissipation-Max (Abs) | 77W |
| Pulsed Drain Current-Max (IDM) | 8.5A |
| Surface Mount | NO |
| Terminal Form | THROUGH-HOLE |
| Terminal Position | SINGLE |
| Transistor Application | SWITCHING |
| Transistor Element Material | SILICON |
| Package | Transistor Outline, Vertical |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| Country of Origin | Mainland China |
Alternate & Equivalent Parts
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
What voltage and current ratings define the safe operating area of the STU70R1K3S?
The STU70R1K3S is rated for a drain-source breakdown voltage of 700 V minimum and a maximum continuous drain current of 5 A. These parameters define its suitability for switching topologies connected to rectified 230 VAC mains, where peak voltages can reach 650 V or more, and output currents of up to 5 A are needed in flyback and forward converter designs.
How does the 90 mJ avalanche energy rating protect the STU70R1K3S in inductive switching circuits?
The 90 mJ avalanche energy (Eas) rating means the STU70R1K3S can safely absorb 90 millijoules of energy during unclamped inductive switching (UIS) events without device failure. This protects the transistor when inductive loads force the drain voltage above 700 V during turn-off, which occurs in motor drive auxiliary supplies, relay driver circuits, and switching power supplies with incomplete snubber designs operating from high-impedance mains.
For a 30 W flyback converter, how much conduction loss does the STU70R1K3S introduce at full load?
At 5 A peak drain current and a typical on-resistance of 1.3 Ω, the STU70R1K3S introduces approximately P = I²·Rds(on) = 5² × 1.3 = 32.5 mW of instantaneous conduction loss per switching cycle. For a 30 W flyback converter with a duty cycle of 40%, the average conduction loss is around 13 mW, representing less than 0.1% efficiency impact, which is acceptable for cost-sensitive adapter and LED driver designs.
What is the feedback capacitance of the STU70R1K3S and why does it matter in high-frequency designs?
The STU70R1K3S has a maximum reverse transfer capacitance (Crss, feedback cap) of 0.43 pF. This low Crss minimizes the Miller effect during fast switching transitions above 100 kHz, reducing gate charge requirements and switching losses. Low feedback capacitance is critical in resonant LLC converters and high-frequency flyback designs where switching speeds above 200 kHz are used to reduce transformer size.
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