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Quantum Corp. - Wikipedia, the free encyclopedia

Quantum Corp.

From Wikipedia, the free encyclopedia

Quantum Corporation
Type Public (NYSEQTM)
Founded 1980
Headquarters San Jose, California, USA
Industry Data storage
Products Magnetic tape data storage, data deduplication technology, and related
Website www.quantum.com

Quantum Corporation is a manufacturer of tape drive, tape automation, data deduplication storage products and scalable file storage software, based in San Jose, California. From its founding in 1980 until 2000, it was also a major disk storage manufacturer (usually #2 in market share behind Seagate), and was based in Milpitas, California.

Quantum got its start when executives and designers from Shugart Associates, IBM and Memorex came up with an idea for an 8-inch hard drive that would achieve decent performance without the cost or complexity of using a full closed-loop servo system — a difficult task before the advent of dedicated servo ICs and readily-available DSPs.

Contents

[edit] Early products

Quantum's first products were very popular; according to one of the company's historical documents, by 1982 it had a 25% share of the market. It designed smaller ST-506-compatible versions of its hard drives, the Q500 series, using the same servo system. It also introduced (through its Plus Development division) what would be most people's introduction to the company, the Plus HardCard, in 1985. The HardCard was essentially a smaller version of the Q500, designed to fit in an ISA slot, with an embedded controller card bolted to the same frame as the drive. The product sold very well, and inspired several other companies to put hard drives on an ISA-format card; this was not as desirable as the Quantum solution at first, since most 3.5-inch drives in the late 1980s were half-height (1.6 inch/40.6 mm) models and thus could not fit in a single ISA slot. The HardCard was originally introduced in a 10 MB and 20 MB model, with a 40 MB model introduced in 1987; the line ended with the 52 and 105 MB HardCard II XL models (based on the ProDrive LPS 52/105) in 1990.

Not long after this, Quantum decided it would enter the then brand-new SCSI market. The first drive it designed especially for SCSI was the Q280 80MB drive, which was released in 1986 and had an average seek time of 30 milliseconds — quite good for the era. The Q280 was also one of the first mass-market drives (along with Conner Peripherals' products) to use embedded servo. Later on, Quantum combined the Q280's embedded controller design with the servo hardware from the Q500 series, and developed the ProDrive range, which was also its first drive family to support the ATA interface. The two design platforms (optical assist and full embedded servo) co-existed until the early 1990s; by then, areal density was high enough to make the gratings impractical, and advancements in embedded servo technology had made the technology economical enough to use in low-end drives.

[edit] Glass scale technology

When the company was started, low end drives generally used stepper motors, just like floppy disk drives did. Steppers worked, but were slow, noisy, and prone to reliability problems due to changes in temperature. The idea the founders had was to combine the predefined steps of a stepper motor, and the accuracy of a closed-loop servo. Their solution was to use an optical positioning system to guide the actuator arm in "gross motor" movements and to only use the closed-loop servo for precisely aligning the heads to a specific track.

Quantum referred to this part in their documentation as a "glass scale", and it was attached to the actuator arm. The scale was a small, light, very thin piece of glass whose surface had an array of narrow chromium plated lines separated by equal widths of clear glass. The pitch of the lines matched the track pitch on the disk. Immediately below the scale was a glass reticle, under which was a matching quad photo detector array. The reticle had four openings, one above each cell of the photo array, and each opening was plated with a pattern of lines that matched those on the scale. The phase relationship between the lines in each of the four windows (relative to the scale) was 0°, 90º, 180º and 270º. This allowed for quadrature detection of exact track position and direction of head movement. This optical system was illuminated by an overhead IR LED that sent light through the scale and the reticle into the quad photo detector. During a seek, the system merely needed to count the number of track crossings seen by the detector array to know when it was approaching the desired track.

This saved quite a bit of hardware as it only required a single 8-bit microcontroller to handle the entire servo system. The 40 MB Q2000 and 80 MB Q4000 were the first drives to use this technology. Later on, as track pitch narrowed, diffraction become a problem, and the decision was made to discontinue the system in favor of fully magnetic embedded servo. The last drives to use the optical assist system were the ProDrive LPS 120 and 240 "Gemini" models, released in 1991.

[edit] Outsourcing

Because of the demand for its drives, Quantum decided early on to outsource its manufacturing, unlike most of its competitors, who decided to stay completely vertically integrated and had opened plants of their own in Singapore, Ireland, Malaysia and Hong Kong. In 1984, Quantum signed an agreement with Matsushita to produce its mass-market drives and the HardCard in the Matsushita Kotobuki Electronics (MKE) factory in Ipponmatsu, Japan. By the late 1990s, all of Quantum's disk products would be produced in Matsushita factories.

[edit] Transformation

[edit] DEC storage group acquisition

In 1994, Quantum purchased DEC's data storage division.[1][2] This gave Quantum access to the DLT streaming tape system, as well as Digital's high-end SCSI drive expertise in Shrewsbury, Massachusetts. The StorageWorks brand of disk arrays was not included in the deal.

DEC's Shrewsbury design team was originally tasked with developing storage products for DEC computer systems and was known as the Low End Disk Systems (LEDS) group. LEDS had been designing hard disk drives for DEC since the 1970s, but their first publicly available product was released in 1993. This product was the RZ72, a 2 GB, 5.25" full-height, SCSI disk. Technology developed by the Shrewsbury team was also used by DEC's tape storage team to make DLT.

After the acquisition, Quantum tasked the Shrewsbury design team with developing the Atlas series of high-performance 10k (and later 15k) SCSI disks. Quantum's Milpitas design team was directed to focus on the high-value segment of the disk market and came up with the Viking, Phoenix and Katana designs.

Due to widespread Y2K fears, and the associated desire to safeguard data, the DLT product line had a large increase in sales in the late 1990s. As a result, Quantum split the company into two parts, one for the DLT products, and one for hard disk drives.

[edit] Hard disk technology sell off

Quantum made a few missteps during the late 1990s. After hitting its peak with the Fireball AT 1080 and Fireball AT 1280 (both high-performance 5400 rpm models), it skewed briefly toward "value" drives that concentrated more on capacity than speed or performance. The Bigfoot drive was the best-known product of this era; it used a 5.25-inch form factor and larger disks to increase drive capacity without forcing an increase in areal density. However, the Bigfoot drives had slow spindles (the first ones ran at only 3600 rpm, long obsolete by then), and the larger disk diameters meant the heads had to move farther when seeking. They were thus generally disliked by "power users", and found their way mostly into inexpensive brand-name PCs.

Quantum also applied the "Fireball" name (which had previously been reserved for the high-end 1080 and 1280 models) to a new "TM" model that featured better throughput, but slower seek times due to a 4500 rpm spindle. Later versions of the Fireball series reversed this trend, and eventually a 7200 rpm Fireball Plus ATA version was released, being one of the first mainstream consumer-oriented 7200 rpm drives. The first of the Plus series was the Fireball Plus KA, a drive available in sizes up to 18.2 gigabytes, and equipped with the new Ultra DMA 66 interface.

By 2000, the hard drive market was getting squeezed. Personal computer sales were dropping, value drives had razor-thin margins and were only getting thinner, and several makers (notably Western Digital) were in trouble. Quantum decided to sell its hard drive division to Maxtor at this time. Maxtor continued most of Quantum's disk storage products and brands until it was acquired by Seagate Technology in 2006. As of 2007, the Shrewsbury design group is alive and well under Seagate's ownership. [3]

Quantum purchased Meridian Data, developer of the Snap Server line of network attached storage products in 1999. This division was spun off in 2002 as Snap Appliance and was subsequently acquired by Adaptec in 2004.

[edit] Tape technology acquisition

A couple years prior to the 2000 sell off of the hard drive division, Quantum began a series of tape technology acquisitions:

  • 1998 - ATL Products, a manufacturer of automated tape libraries. [4]
  • 2001 - M4 Data (Holdings) Ltd., a manufacturer of tape libraries. [5]
  • 2002 - Benchmark Storage Innovations, who manufactured the VStape product line under a Quantum license. [6]
  • 2005 - Certance, the former tape business of Seagate Technology, becoming a member of the LTO consortium. [7]
  • 2006 - Advanced Digital Information Corporation (ADIC), for about $770 million. [8]

As of 2007, Quantum is a leading manufacturer of tape drives and tape libraries.

[edit] References

  1. ^ Announcement of DEC storage acquisition.
  2. ^ More details of DEC storage deal.
  3. ^ Seagate locations, including Shrewsbury
  4. ^ SEC filing about ATL acq.
  5. ^ SEC filing about M4 Data acq.
  6. ^ CRN article about Benchmark acq.
  7. ^ Certance acq.
  8. ^ Press release about ADIC acq.


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