Write driver using continuous damping network to reduce overshoot, undershoot and settling time for magnetic inductive recording head

摘要

A write driver circuit for selectively controlling a direction of write current flow through a magnetic head having an inductive coil includes a source of first and second write currents. A forward drive switch directly sinks the first write current and sinks the second write current through the coil in a first direction. A reverse drive switch directly sinks the second write current and sinks the first write current through the coil in a second direction opposite the first direction. A control circuit operates the forward and reverse drive switches so that write current flows through the coil in a selected direction. An overshoot reduction circuit may be provided to reduce write current overshoot through the coil. An active subcircuit generates a compensation signal based on a voltage across the head exceeding a predetermined threshold. The first and second write currents are adjusted in response to the active subcircuit based on the compensation signal.