Abstract: A gradient amplifier system is presented. An embodiment of a gradient amplifier system that includes a power stage having a plurality of bridge amplifiers, where each of the plurality of bridge amplifiers operates at a first switching frequency. The gradient amplifier system further includes a gradient coil coupled to an output terminal of the power stage and configured to produce a magnetic field proportional to a coil current signal supplied by the power stage. In addition, the gradient amplifier system includes a controller stage coupled to an input terminal of the power stage and configured to generate a pulse width modulated gate signal based on the coil current signal and a reference current signal, where the pulse width modulated gate signal is generated at a second switching frequency upon occurrence of a slew rate associated with the reference current signal is below a determined threshold rate and an amplitude level associated with the reference current signal is above a determined level.

Abstract: A gradient amplifier system is presented. An embodiment of a gradient amplifier system that includes a power stage having a plurality of bridge amplifiers, where each of the plurality of bridge amplifiers operates at a first switching frequency. The gradient amplifier system further includes a gradient coil coupled to an output terminal of the power stage and configured to produce a magnetic field proportional to a coil current signal supplied by the power stage. In addition, the gradient amplifier system includes a controller stage coupled to an input terminal of the power stage and configured to generate a pulse width modulated gate signal based on the coil current signal and a reference current signal, where the pulse width modulated gate signal is generated at a second switching frequency upon occurrence of a slew rate associated with the reference current signal is below a determined threshold rate and an amplitude level associated with the reference current signal is above a determined level.