Welcome to GPA-FHDO’s documentation!

This Gradient Power Amplifier (GPA) has 4 channels, of which each can drive a current of +- 10 A. The current is controlled via an SPI interface. The GPA has a build in current sensor for each channel that is also controlled via SPI. The information from the current sensor can be used for automatic calibration of the GPA.

Warning

Disclaimer: Not intended for medical use!

Contents:

• General Overview
• Function Overview
• Connections
  • Connecting the PCB to the power supply
  • Connecting the PCB to the via SPI to the microcontroller
  • Connecting the PCB to the gradient coils (or dummy loads)
• Controlling the DAC and ADC via SPI
• Adapting the resistor and capacitor values
• Choosing the Optimal Power Supply
  • Necessary Voltage for a certain Coil Current
  • Heat Dissipation
• Automatic calibration using the Arduino code
  • Details about the calibration procedure
• Measured Performance
  • Measurement Conditions
  • Temperature Stability Analysis
  • Linearity Analysis
• Maximum ratings
• Parts list
  • version 1.3
  • version 1.2
• Assembly Instructions

Contributing

• Jason Stockmann

• Nicolas Arango

• Odin Holmes

References

• https://tabletop.martinos.org/index.php/Hardware:GPA

• https://rflab.martinos.org/index.php/Current_driver:Current_driver

Source Code

• https://github.com/menkueclab/GPA-FHDO

Indices and tables

• Index

• Search Page