Neural stimulator systems with an external magnetic coil to produce changing magnetic fields is applied outside the body, in conjunction with one or more tiny injectable objects that concentrates the induced electric or magnetic field to a highly-targeted location. These systems include a driver circuit for the magnetic coil that allows for high voltage and fast pulses in the coil, while requiring low-voltage power supply that may be powered by a wearable or portable external device, along with the coil and driver circuit.
