US 12,249,349 B1
Rotation filter for digital timing recovery in hard disk drive read channel
Nitin Nangare, Sunnyvale, CA (US); and William J. Mitchem, Broomfield, CO (US)
Assigned to Marvell Asia Pte Ltd, Singapore (SG)
Filed by Marvell Asia Pte Ltd, Singapore (SG)
Filed on Mar. 4, 2024, as Appl. No. 18/594,142.
Claims priority of provisional application 63/450,656, filed on Mar. 7, 2023.
Int. Cl. G11B 20/10 (2006.01)
CPC G11B 20/10055 (2013.01) [G11B 20/10037 (2013.01); G11B 20/10259 (2013.01)] 25 Claims
OG exemplary drawing
 
1. A method for digital timing recovery from oversampled analog signals, the method comprising:
computing filter coefficients for digitized samples of the oversampled analog signals based on an oversampling factor of the oversampled analog signals;
using the filter coefficients in a rotation filter to compensate for the oversampling factor in the digitized samples of the oversampled analog signals;
deriving a starting phase and magnitude from the compensated digitized samples of the oversampled analog signals; and
using the starting phase and magnitude in a timing recovery loop to recover a clock from the compensated digitized samples of the oversampled analog signals.