History 1999: Read-Rite at 36Gb Per Square Inch with HMT and Marvell

With the aid of HMT Technology and Marvell Semiconductor, Read-Rite has taken a slight lead over IBM, at 35.3Gb per square inch, with the recent demonstration of 36Gb per square inch areal density, meaning roughly 50GB per 3.5-inch magnetic disk platter.

This record was accomplished using Read-Rite’s dual spin valve trimmed GMR pico head, HMT low-noise, low-glide and thermally stable media, produced on NiP coated aluminum substrates, and a trellis-coded noise predictive read channel from Marvell.

This 36Gb per square inch areal density breaks down to 511,000bpi and 70,400tpi. Data rates hit 21.7MB/s. The ontrack error rate was less than one error over a billion bits read with over 22% off-track capability.

This article is an abstract of news published on issue 143 on December 1999 from the former paper version of Computer Data Storage Newsletter.