Hard disk drive preamplifier write driver

摘要

The present invention discloses an apparatus (160) comprising a common mode generator circuit (162) coupled to a current directing circuit adapted to provide current to a first write head connection node (170) and to a second write head connection node (172). The common mode generator circuit (162) is adapted to provide additional current to the first write head connection node (170) and to the second write head connection node (172), wherein the first write head connection node (170) is adapted to produce a first write signal, wherein the second write head connection node (172) is adapted to produce a second write signal, wherein the current and the additional current are adapted to establish a voltage across the first write head connection node (170) and the second write head connection node (172), wherein the voltage is adapted to be pulled toward a first polarity based on the first write signal and toward a second polarity based on the second write signal, and wherein the voltage pulled toward the first polarity and the voltage pulled toward the second polarity are substantially centered about a common mode voltage.