Pulser Mark 5
48 Channel Bipolar 650 V Ultrasound Phased Array
Xilinx Spartan 6 FPGA phase controller (based on Papilio Pro development hardware)
Custom VHDL phase generation source code on FPGA
GUI and command line control of burst train and phase parameters on Linux host
Array of discrete Class D amplifiers: Navitas NV6252 Gallium Nitride FETs
High current capacitor power supply, charged with ZVS flyback powered by a small switching supply
Control and power stages fully opto-isolated with optical fiber links
VTK-based volumetric rendered 3D graphics for control of source and target points
FPGA Control Module
Phase generation and control is achieved with a low cost Papilio Pro board with a Xilinx Spartan 6 FPGA. Internal synthesized 256 Mhz clock, for phase delay increments of 3.9 ns. No vendor-specific ip is used except for the clock multiplier block.
Parallel low-cost ultrasound amplifiers, one amplifier per channel. Navitas NV6252 GaN FET half bridge, 200 V/ns slew. Optoisolated by 50 MB/s Broadcom optical receivers (AFBR-2624Z) using inexpensive 1mm plastic optical fiber. These Class D amplifiers were developed in-house by Pataphysics Research.
Our custom VTK-based 3D visualization software allows dynamic control of ultrasonic source and deep brain target coordinates. A commodity 3D scanner (Kinect) is used to match real-world to CT or MRI scan data in a virtual stereotaxic system.