A magnetic secure transmission driver system for emitting a magnetic field, the system comprising: a step-down DC-DC buck converter coupled to a battery 2. and a capacitor for outputting a stepped-down voltage from the battery and the capacitor; a driver coupled to the stepped-down voltage output by the buck converter and configured to control polarity of a current through a first inductor through a full bridge circuit of the driver; and an over voltage protection circuit (351 and 352) coupled to the first inductor and configured to protect the driver, wherein the driver comprises: a first switch of the driver coupled between the voltage output by the buck converter and a first circuit node; a second switch of the driver coupled between the voltage output by the buck converter and a second circuit node; a third switch of the driver coupled between the first circuit node and ground; a fourth switch of the driver coupled between the second circuit node and ground; and a controller configured to control the first through fourth switches of the driver; wherein: the first circuit node is coupled to a first lead of the first inductor through the over voltage protection circuit, the over voltage protection circuit being coupled to the controller; and the second circuit node is coupled to a second lead of the first inductor, and wherein the controller is further configured to control current through the third and fourth switches of the driver to adjust a slew rate of current through the first inductor. a step-down DC-DC buck converter coupled to a battery 2. and a capacitor for outputting a stepped-down voltage from the battery and the capacitor; a driver coupled to the stepped-down voltage output by the buck converter and configured to control polarity of a current through a first inductor through a full bridge circuit of the driver; and an over voltage protection circuit (351 and 352) coupled to the first inductor and configured to protect the driver, a first switch of the driver coupled between the voltage output by the buck converter and a first circuit node; a second switch of the driver coupled between the voltage output by the buck converter and a second circuit node; a third switch of the driver coupled between the first circuit node and ground; a fourth switch of the driver coupled between the second circuit node and ground; and a controller configured to control the first through fourth switches of the driver; wherein: the first circuit node is coupled to a first lead of the first inductor through the over voltage protection circuit, the over voltage protection circuit being coupled to the controller; and the second circuit node is coupled to a second lead of the first inductor, and wherein the controller is further configured to control current through the third and fourth switches of the driver to adjust a slew rate of current through the first inductor. the first circuit node is coupled to a first lead of the first inductor through the over voltage protection circuit, the over voltage protection circuit being coupled to the controller; and the second circuit node is coupled to a second lead of the first inductor, and wherein the controller is further configured to control current through the third and fourth switches of the driver to adjust a slew rate of current through the first inductor.