US 11,735,214 B2
Synchronous writing of patterned media
Jason Bellorado, San Jose, CA (US); Marcus Marrow, San Jose, CA (US); and Zheng Wu, Los Altos, CA (US)
Assigned to Seagate Technology LLC, Fremont, CA (US)
Filed by Seagate Technology LLC, Fremont, CA (US)
Filed on Aug. 18, 2022, as Appl. No. 17/890,580.
Application 17/890,580 is a division of application No. 17/345,759, filed on Jun. 11, 2021, granted, now 11,475,912.
Prior Publication US 2022/0399037 A1, Dec. 15, 2022
Int. Cl. G11B 5/596 (2006.01); G11B 5/012 (2006.01)
CPC G11B 5/59616 (2013.01) [G11B 5/012 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An apparatus comprising:
an integrated circuit including:
a detector circuit configured to detect a bit sequence read from a patterned medium;
a data generator circuit coupled to a delay line and configured to generate bits of a known data pattern;
multiple bit-error counters coupled to the delay line and each configured to compare a bit or shifted bit of the known data pattern to a bit of the detected bit sequence and count a number of bit-errors over a period of time;
a control circuit configured to count a number of bits processed by the bit-error counters;
multiple registers, each of the multiple registers configured to store a result of a corresponding bit-error counter over the period of time; and
an adjustment circuit configured to modify a count of grain patterns between two servo wedges of the patterned medium based on the results of the bit-error counters stored in the registers, the adjustment circuit further configured to store the modified count of grain patterns to enable synchronous writing of the patterned medium.