Selectable current booster circuit

A magnetic recording write driver system, comprising:

• a bridge circuit configured to provide bidirectional write currents to a magnetic recording head, the bridge circuit including a first branch and a second branch, each branch having an upper transistor and a lower transistor;
• a plurality of current boost circuits, each current boost circuit including a pre-biased transistor configured to generate current pulses having durations shorter than bridge circuit current transitions;
• a transmission line coupled to the bridge circuit;
• and
• a magnetic recording head coupled to the transmission line, wherein the current boost circuits reduce current transition times at the magnetic recording head during data writing operations.

A hard disk drive write driver system, comprising:

• a bridge circuit including a first branch and a second branch configured to generate bidirectional write currents, each branch including complementary bipolar transistors;
• a first set of boost circuits coupled to the first branch, including a positive boost circuit and a negative boost circuit;
• a second set of boost circuits coupled to the second branch, including a positive boost circuit and a negative boost circuit;
• a control circuit configured to coordinate activation of the boost circuits with switching transitions of the bridge circuit;
• an impedance matching network;
• and
• a magnetic recording head coupled through a transmission line, wherein the boost circuits accelerate current transitions at the magnetic recording head for high-speed data writing.