Mark Steven Chambers

US Patent:

7715143, May 11, 2010

Filed:

Dec 28, 2007

Appl. No.:

11/965777

Inventors:

William Gene Bliss - Thornton CO, US
Mark Chambers - Laguna Hills CA, US

Assignee:

Broadcom Corporation - Irvine CA

International Classification:

G11B 21/04

US Classification:

360 70

Abstract:

A disk drive controller includes a servo system operable to associate a time stamp with an arrival of a servo wedge, a firmware loop and core PLLs in the read channel. The firmware loop is operable to determine a period between the arrival of a pair of consecutive servo wedges and produce a desired frequency of when to read/write data to disk based on the period between the arrival of a pair of consecutive servo wedges. Processing circuitry is operable to adjust a clock signal, wherein the clock signal itself is not locked to the data and produce a fine control signal for the core PLLs in the read channel. These core PLLs are operable to determine a phase and/or frequency associated with when an analog signal is sampled and/or written to disk, wherein these core PLLs comprises Fractional N Sigma Delta PLLs.