  Cold atom experiments commonly use broad magnetic Feshbach resonances to
manipulate the interaction between atoms. In order to induce quantum dynamics
by a change of the interaction strength, rapid ($\sim\mu s$) magnetic field
changes over several tens of Gauss are required. Here we present a compact
design of a coil and its control circuit for a change of the magnetic field up
to $36G$ in $3\mu s$. The setup comprises two concentric solenoids with minimal
space requirements, which can be readily added to existing apparatuses. This
design makes the observation of non-equilibrium physics with broad Feshbach
resonances accessible.
