US 11,869,546 B1
Adaptive dual heater mode for hard disk drive
Qinghua Zeng, Fremont, CA (US); Noureddine Kermiche, Dana Point, CA (US); Kazuhiro Saito, Salt Lake City, UT (US); and Bernhard E. Knigge, San Jose, CA (US)
Assigned to Western Digital Technologies, Inc., San Jose, CA (US)
Filed by Western Digital Technologies, Inc., San Jose, CA (US)
Filed on Jul. 27, 2022, as Appl. No. 17/874,903.
Int. Cl. G11B 5/54 (2006.01); G11B 5/012 (2006.01); G11B 13/08 (2006.01); G11B 5/00 (2006.01)
CPC G11B 5/012 (2013.01) [G11B 13/08 (2013.01); G11B 2005/0021 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A data storage device comprising:
a disk;
a plurality of read/write heads, each read/write head having a read portion configured to read data from the disk and a write portion configured to write data to the disk, each read/write head comprising:
a read heater disposed proximate to the read portion and configured to thermally adjust a read spacing of the read portion from a surface of the disk;
a write heater disposed proximate to the write portion and configured to thermally adjust a write spacing of the write portion from the surface of the disk; and
a controller configured to:
for each read/write head, control power applied to the read heater and power applied to the write heater based on a dual heater power ratio (DHR) of the respective power applied to each of the read heater and the write heater,
wherein the DHR is set based on a point during touchdown at which a reader shield and a writer shield have maximum contact with the surface of the disk (DHRmax), and wherein DHRmax is determined on a per-head basis.