Bidirectional Mosfet Switch Board (3300V)

Our next-generation Bidirectional MOSFET Switch (3300V) is the most advanced high-voltage AC switch in this class, completely redesigned from the ground up for extreme speed, stability, and thermal performance. Built around TO-263-7 MOSFET packages, this revision minimizes gate-loop inductance, integrates a brand-new isolated high-speed gate driver, and introduces a substantially improved cooling solution—enabling reliable operation deep into the multi-MHz range. Optimized for resonant and high-frequency AC operation, the architecture delivers the following key advantages:

• 3300V Bidirectional High-Voltage Operation: Designed for demanding AC applications, this switch uses two high-voltage MOSFETs in a back-to-back (common-source) configuration, allowing safe and efficient bidirectional current blocking at voltages up to 3300V.
   
• Ultra-Fast ~5ns Switching: A completely new isolated gate driver combined with an ultra-low-inductance layout enables switching transitions as fast as 5 ns (MOSFET- and load-dependent), making this one of the fastest bidirectional high-voltage switches available.
   
• Isolated Control and Power Domain: Logic input and power supply rails are fully isolated from the MOSFET/output side. This prevents noise injection, protects external equipment, eliminates ground loops, and enables floating or high-side configurations.
   
• Minimized Gate-Loop Inductance: The PCB layout has been fully optimized to reduce gate-loop inductance, resulting in cleaner edges, reduced ringing, and stable operation at very high switching frequencies.
   
• Advanced Thermal Architecture: Heat dissipation has been dramatically improved through a combination of dedicated heatsinks mounted directly on the MOSFETs and large copper areas that are in direct thermal contact with the drain pads. This allows sustained high-speed operation without thermal stress.
   
• Integrated Active Cooling: The board provides 12 V fan output via both an XH2.54 connector and a 2-port screw terminal. A silent maglev fan is included and pre-connected to the XH2.54 port, ensuring efficient, quiet cooling and enabling reliable multi-MHz operation.
   
• High-Frequency AC Capability: While performance depends on MOSFET gate capacitance and load conditions, the board comfortably supports frequencies above 1 MHz and has been tested at 3 MHz and beyond with suitable devices.
   
• Essential for Resonance Circuits: True bidirectional current blocking makes this switch indispensable in resonant AC systems where current alternates direction every half-cycle.
   
• High-Side or Low-Side Switching: The flexible topology allows use in both high-side and low-side switching configurations, depending on system requirements.
   
• 3.3V & 5V Logic Compatible: Fully isolated control input supports both 3.3 V and 5 V logic levels, allowing direct connection to microcontrollers for precise, programmable switching control.
   
• Selectable 50-Ohm Input Termination: A switchable 50 ohm impedance-matching resistor is included on the input, which is highly beneficial for maintaining signal integrity during high-frequency operation with standard signal generators and coaxial cables.
   
• Built-In Fuse Protection: An onboard fuse adds an extra layer of safety, protecting the MOSFETs and gate driver circuitry during overcurrent or fault conditions.
   
• High-Current Terminals: Heavy-duty screw terminals support AWG10 wire, ensuring secure, low-loss connections for high-current operation.
   
• BNC Connection for Ease: A dedicated BNC connector provides a clean, reliable interface to function generators and laboratory signal sources.

The Bidirectional MOSFET Switch (3300V) is a powerful platform for advanced AC and resonant circuit experimentation, combining extreme switching speed, galvanic isolation, high-voltage capability, and robust thermal design. It is ideally suited for researchers and engineers pushing the limits of high-voltage, high-frequency electronics.

For users who prefer device-level flexibility, this platform is also available in a TO-247-4 socketed configuration supporting up to 3300 V. Compared to the integrated TO-263-7 implementation, this variant is marginally slower in maximum switching speed, but allows easy MOSFET replacement and experimentation with different devices—making it particularly well suited for development work, characterization, and iterative testing.

Technical Specification:

Datasheets for the selectable MOSFETs can be found here: G2R120MT33J and G2R1000MT33J

Note: Best-case switching times refer to light capacitive discharge; typical values reflect heavier load operation. Speed is primarily determined by MOSFET gate capacitance, supply impedance, and load conditions — not the board itself.

This product includes a BNC to hookup wire adapter and a pre-installed silent maglev cooling fan for immediate use.