The case for continued support for the 1.8-inch hard disk drive

Implications: Toshiba introduced a 1.8-inch form factor hard disk drive with storage capacities as high as 160 GB.This is a 2 platter product with areal densities as high as 228 gigabits per square inch.In addition to higher storage capacity the product also uses about one third less power to operate than earlier 1.8-inch products geared towards the consumer market.Apple is using Toshiba 80 GB and 180 GB 1.8-inch drives in their new line-up of iPod Classic video players.1.8-inch hard disk drives will play a very important role in disk drive development and thus this form factor should be defended and preserved.

Analysis: Toshiba announced a 160 GB 1.8-inch disk drive that is now being shipped in the Apple iPod Classic. The iPod classic offers 10 times the storage capacity of smaller iPod players using NAND flash memory for about the same price. Although the 1-inch and smaller drive formats appear to be approaching extinction as flash memory displaces them in MP3 players and rich media cell phones, video on a portable device and richer, non-lossy compressed and non-compressed formats need larger storage capacities than flash memory can provide. The 1.8-inch form factor hard disk drive can provide this level of digital storage at an economically viable price.

This growing demand for richer content on mobile devices has lead to a continued demand for hard disk drives for the Personal Media Player market. Rich video oriented media players need a larger screen and thus don’t have the same pressure to make a smaller device that MP3 players have had.

Thus a small form factor hard disk drive still makes sense for rich video products and could be in even higher demand if ideas such as personal projectors built into mobile devices, such as suggested by display companies such as Novalux come to pass. Such devices could allow projection of a larger high resolution image from a mobile device, putting even greater pressure on digital storage capacity requirements. Rich media mobile products will need the storage capacity possible with 1.8-inch hard disk drives.

In the enterprise storage space 2.5-inch form factor drives are making significant headway against 3.5-inch drives in high performance drive arrays because they offer high performance combined with higher volumetric storage (the amount of bytes that can be stored per cubic length, or volume). Eventual movement to a 1.8-inch form factor product in this industry could improve the volumetric storage density even further while allowing storage across a greater number of drive spindles. The latter allows creation of even higher performance storage arrays. Designing higher volumetric density and higher performing storage arrays will be a key for the high end storage business.

With the rising concern over the energy consumed by and the cost of operating a data center smaller form factor drives could help reduce the overall energy used for spinning the lower inertia disks is less. Smaller form factor drives would also reduce the waste heat generated compared to larger form factor drives.

Over the 50 plus year history of hard disk drives the trend has always been towards moving to smaller form factors over time. In the early history of disk drives, diameters of 3 feet or more were not uncommon. Over time standard disk formats included 18-inches, 8-inches and 5.25-inches. Currently 3.5-inch drive formats are dominant and there are no larger available formats. However 2.5-inch form factor drives are increasing in unit shipments more rapidly than 3.5-inch form factor drives.

As areal density of recording increases the new technologies needed to achieve them are easier to implement on smaller form factor disk drives than on larger form factor drives. The same technologies become hard over time to implement on the larger form factor disks. As a consequence small disk form factors represent the future of disk storage. There is no reason why this should not be true in the future. For this reason hard disk companies need to ensure the continued support for and success of 1.8-inch disk drives. Their future depends upon it!