An all digital controlled current driver is used for each pulsed electromagnet (e.g., gradient coils) in a magnetic resonance imaging (MRI) system. Such an all digital current controller may be advantageously employed in either closed loop or open loop gradient coil control circuits. The elimination...http://www.google.de/patents/US5442290?utm_source=gb-gplus-sharePatent US5442290 - MRI gradient drive current control using all digital controller
