Patent Number: 6,166,869

Title: Method and circuit for enabling rapid flux reversal in the coil of a write head associated with a computer disk drive, or the like

Abstract: An H-bridge for applying a current to a coil of a write head assembly for writing data to a magnetic media includes two pair of two switchable transistors. Each pair of transistors is connected between a supply voltage and a reference potential and is adapted to be connected to the coil between the transistors of each pair for turning the transistors turned on and off in a sequence to control the direction of current flow in the coil. The upper transistors of each pair serves a switching transistor, and the lower transistors provide a mirrored referenced current to the coil. A pair of capacitors are connected to a control element of a respective associated one of the lower transistors, and switching circuitry is connected to the capacitors to selectively connect each of the capacitors to inject current into the control element of the respective associated lower transistor when the respective associated lower transistor is turned on. Also disclosed is a technique for adjusting the amount of boost current injected into the lower transistors.

Inventors: Pidutti; Albino (Udine, IT), Alegre de La Soujeole; Axel (Scotts Valley, CA), Pakriswamy; Elango (Santa Clara, CA)

Assignee: STMicroelectronics, Inc.

International Classification: G11B 5/09 (20060101); H01L 29/00 (20060101); H03K 17/56 (20060101); H02P 6/08 (20060101); H03K 17/74 (20060101); H03K 17/51 (20060101); H02P 7/06 (20060101); G11B 005/09 ()

Expiration Date: 12/26/2017