History (1994): Record for Integral Peripheral: 420MB in PCMCIA III Form Factor

Just how far can capacities of PCMCIA drives go?

The maximum in the 10.5mm thickness was 170MB for Calluna, Maxtor and MiniStor.

But Integral Peripherals (Boulder, CO) has just raised the limits with 3 new 260, 340 and even 420MB units, all numbers without compression. The 1.8-inch form factor Cobalt 420, boasts a previously unheard of 6 platters and 6 heads.

Its capacities, especially the largest one will undoubtedly allow 1.8-inch drives to eat away at part of the HDD market for notebooks, nearly all of which are currently equipped with 2.5-inch internal drives.

In addition to its use of PRML read channel from Cirrus Logic (Fremont, CA), the secret of Cobalt 420 lies in its exploitation of a 4-die multichip module (MCM) from MicroModule Systems (Cupertino, CO). The company provides Integral with the entire drive electronics subassembly. Each MCM is built using multilayer thin-film (MCM-D) technology on an aluminium substrate. Copper is used for all signal traces, with a polyimide dielectric.

The 1.2mm total thickness of the MCM includes the substrate, interconnect, die, and encapsulation. It saves enough space for all of the boards to fit next to and not under the magnetic platters, leaving enough room, a third disk in the 10.5mm thick drive.

This article is an abstract of news published on the former paper version of Computer Data Storage Newsletter on issue 81, published on October 1994.