US 2017/0148472 A1 · CONFIGURABLE WRITE CURRENT OVERSHOOT SYSTEM FOR HDD WRITE DRIVER

Abstract

A hard disk drive write drive method and integrated circuit that provide a configurable overshoot current based on the length of the pattern in the write current signal that is being written to the hard disk by the write driver. The hard disk write driver adds a first overshoot current to all patterns in the write current signal and adds an additional second overshoot current to patterns in the write current signal shorter than a first duration. The hard disk drive write driver utilizes an H-bridge circuit configured to add the first overshoot current and the additional second overshoot current to the write current signal. The H-bridge circuit is comprised of four switching elements that are configured to generate a first overshoot current for all pattern transitions of the write current signal and generate a second overshoot current for pattern transitions shorter than the first duration.

Claims18

Dependent claims

A process of forming a write current signal used in a hard disk drive comprising:

(a) receiving a write data input signal having data pulses, each data pulse having a start transition, an end transition, and a time T in length between transitions, and the time T between transitions of different pulses are integral numbers of time T in length;
(b) generating a write current signal of write pulses having start transitions in accordance with the data pulses of the write data input signal;
(c) determining the lengths T of the data pulses;
(d) for data pulses having a length T greater than 1T, producing a first overshoot current at the start transition of a write pulse for a first time duration and a first current value;
and
(e) for data pulses having a length of 1T, producing a second overshoot current at the start transition of a write pulse for a second time duration and a second current value.

3 more elements

Dependencies are inferred from the claim text.

Configurable write current overshoot system for hdd write driver

Life of this patent

Configurable write current overshoot system for hdd write driver

Life of this patent

Abstract

Claims18