Overview of SiC MOSFET Package Types
AstSiC offers SiC MOSFETs in a variety of package types, each with distinct advantages in terms of thermal performance, parasitic inductance, power handling capability, and assembly method. Understanding these tradeoffs is essential for selecting the optimal device for a given application.
Through-Hole Packages
TO-247-3 (3-Pin)
The traditional 3-pin TO-247 package offers excellent thermal performance with a large lead frame and heatsink mounting surface. However, the shared source pin between power and gate drive paths introduces parasitic inductance that can cause gate bounce during high-current switching. Suitable for applications up to 100A with moderate switching speeds. Available models: ASC100N650MT3 (650V, 100A), ASC60N1200MT3 (1200V, 60A).
TO-247-4 (4-Pin Kelvin Source)
The 4-pin variant adds a separate Kelvin source connection for the gate drive, eliminating power loop inductance from the gate drive path. This enables cleaner switching waveforms, reduced EMI, and higher switching frequencies. Recommended for all high-performance applications. Available models: ASC100N1200MT4 (1200V, 100A), ASC200N1200MT4 (1200V, 200A).
TO-220F (Full Pack)
The TO-220F package provides electrical isolation through a fully molded plastic body, eliminating the need for external insulation between the device and heatsink. This simplifies assembly but results in slightly higher thermal resistance. Available models: ASC30N650MF3 (650V, 36A), ASC25N650MF3 (650V, 25A).
Surface Mount Packages
TOLL (Transistor Outline LeadLess)
The TOLL package offers a compact, low-profile solution with excellent thermal performance through a large drain pad. The leadless design minimizes parasitic inductance, enabling high-frequency operation. Ideal for high-density power supply designs. Available models: ASR12N650MD02 (650V, 100A, 12mΩ), ASR35N650MD02 (650V, 60A, 35mΩ).
PDFN8x8
The PDFN8x8 (Power Discrete Flat No-lead 8x8mm) package provides the smallest footprint for SiC MOSFETs in the AstSiC portfolio. Its direct-backside cooling capability enables efficient heat extraction with minimal thermal path. Available models: ASR35N650MD88 (650V, 60A, 35mΩ), ASR320N650MD88 (650V, 8A, 320mΩ).
PDFN5x6
The PDFN5x6 is the smallest package option, suited for low-power applications where space is at a premium. Available models: ASR320N650MD56 (650V, 8A, 320mΩ).
TO-263-7 (D2PAK-7)
The TO-263-7 package combines the power handling of through-hole packages with the assembly convenience of surface mount. The 7-pin version provides Kelvin source connection. Available models: ASC60N650MT7 (650V, 60A), ASC30N650MT7 (650V, 36A).
Specialized Packages
TOLT (TO Leadless Top)
The TOLT package provides top-side cooling capability, enabling thermal management independent of the PCB. This is particularly valuable in high-density designs where PCB copper area is limited. Available for 1200V applications with 60-75A current ratings.
QDPAK (Quad Flat Package)
The QDPAK package offers high current capability in a surface-mount form factor, with optimized pinout for low parasitic inductance. Available for 1200V, 75A applications with 30mΩ RDS(on).
DT3PAK (Dual Cool 3-Pin)
The DT3PAK enables dual-side cooling for enhanced thermal performance in a surface-mount package. Available for 650V applications with 36-60A current ratings.
Selection Criteria Summary
When selecting a package, consider: (1) Power level and current requirement, (2) Switching frequency and parasitic inductance tolerance, (3) Thermal management strategy (bottom-cooled vs top-cooled), (4) Assembly method (through-hole vs surface mount), (5) Isolation requirements, and (6) Board space constraints. For new designs, the 4-pin Kelvin source packages (TO-247-4, TOLL) are strongly recommended to maximize SiC performance benefits.
