Content last revised on January 10, 2026
SEMIKRON SKKD170F12 Fast Recovery Diode Module | High-Efficiency Power Rectification
The SEMIKRON SKKD170F12 is a high-performance fast diode module engineered for demanding power conversion applications. Housed in the industry-proven SEMIPACK® 2 package, this 1200V, 170A module combines robust construction with superior electrical characteristics, making it an essential building block for controlled rectifiers, AC controllers, and as a freewheeling diode in high-frequency inverter systems.
Unpacking the Technical Advantages of the SKKD170F12
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Fast and Soft Recovery Characteristics
Technical Principle: The SKKD170F12 is designed with optimized carrier lifetime control, resulting in extremely fast reverse recovery time (trr). Crucially, it features a "soft" recovery behavior. This means the reverse recovery current subsides gradually rather than snapping off abruptly, which significantly dampens high-frequency oscillations.
Application Value: This soft recovery profile minimizes voltage overshoot (V_RRM) during switching, reducing the electrical stress on companion components like IGBTs. It leads to lower radiated electromagnetic interference (EMI), simplifying the design and cost of snubber circuits and EMI filters. For engineers, this translates to faster design cycles and a more reliable end-product.
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Superior Thermal Performance and Isolation
Technical Principle: The module utilizes a Direct Bonded Copper (DBC) substrate, which provides excellent thermal conductivity while ensuring high electrical isolation (3000V). This construction, combined with SEMIKRON's pressure contact technology, ensures a low thermal resistance path from the silicon die to the heatsink.
Application Value: Efficient heat dissipation allows the module to operate reliably at higher power densities or in challenging ambient conditions. The isolated baseplate simplifies assembly, as multiple modules can be mounted on a single, non-isolated heatsink, reducing mechanical complexity and system cost. This is a core element of effective IGBT thermal design and contributes directly to a longer operational lifespan.
Key Technical Specifications
| Parameter | Value |
|---|---|
| Repetitive Peak Reverse Voltage (V_RRM) | 1200 V |
| Average Forward Current (I_FAV) @ Tc=85°C | 170 A |
| Forward Voltage (V_F) @ I_F = 400A, Tj=25°C | 1.85 V (max) |
| Reverse Recovery Time (t_rr) @ Tj=125°C | 2.1 µs (typ.) |
| Isolation Voltage (V_isol) | 3000 V~ (2500 V~) |
| Package | SEMIPACK® 2 |
Application Scenarios: Where the SKKD170F12 Excels
- High-Power Rectifiers for UPS and Welders: In the input stage of an Uninterruptible Power Supply (UPS) or welding equipment, the SKKD170F12 provides efficient and robust AC-to-DC conversion. Its high current capability and low forward voltage drop minimize conduction losses, improving overall system efficiency.
- Freewheeling Diodes in Motor Drives: When used as an anti-parallel diode for an IGBT in a motor drive, its fast and soft-recovery diode characteristics are paramount. It safely handles the freewheeling current from the motor's inductance, protecting the IGBT and reducing switching losses, which is critical for achieving high efficiency in industrial automation systems.
- AC Controllers and Soft Starters: The module can be configured in a back-to-back SCR topology for AC power control. This is ideal for soft starters for large motors, where it limits inrush current, or for industrial heating controls, providing precise power regulation.
Selection Guidance: SKKD170F12 vs. Alternative Solutions
Compared to standard, slower recovery rectifier diodes, the SEMIKRON SKKD170F12 is the definitive choice for applications involving high switching frequencies or high di/dt rates. While standard diodes may suffice for simple 50/60Hz rectification, they introduce significant switching losses and EMI challenges in modern power conversion circuits. The investment in a fast recovery module like the SKKD170F12 pays dividends in system performance, reliability, and reduced filtering requirements.
For engineers seeking even higher levels of integration, PIM (Power Integrated Module) or CIB (Converter-Inverter-Brake) modules might be an option. However, using a discrete module like the SKKD170F12 offers superior design flexibility, allowing for optimized thermal management of the rectifier stage and simpler field serviceability. To find the right component for your specific power stage, explore more IGBT modules or contact us for a quote on your project requirements.
