Weitek

Weitek Corporation

Company type	Private
Industry	Semiconductors
Founded	1981
Defunct	1996
Fate	1996 acquired by Rockwell's Semiconductor Systems
Headquarters	San Jose, California
Products	microprocessors, chipset

Weitek 4167 for i486-based computers

Architecture of Weiteks WTL 1167

Weitek SPARC Power µP

Weitek Power9100

Weitek Corporation was a chip-design company that originally focused on floating-point units for a number of commercial CPU designs. During the early to mid-1980s, Weitek designs could be found powering a number of high-end designs and parallel-processing supercomputers. During the early 1990s most CPU designs started including FPUs built into the system, basically “for free”, and Weitek made a series of attempts to break into the general CPU and graphics driver market. By 1995 the company was almost dead, and in late 1996 the remains were purchased by Rockwell's Semiconductor Systems and quickly disappeared.

Weitek started in 1981, when several Intel engineers left to form their own company. Weitek developed math coprocessors for several systems, including those based on the Motorola 68000 family, the 1064, and for Intel-based i286 systems, the 1067. Intel's own FPU design for the i386 fell far behind in development, and Weitek delivered the 1167 for them. Later upgrades to this design led to the 2167, 3167 and 4167. Weitek would later deliver similar FPUs for the MIPS architecture, known as the XL line. Weitek FPUs had several differences compared to x87 offerings, lacking extended double precision but having a register-file rather than a stack-based model.

As orders increased for supercomputer applications, Weitek found themselves seriously disadvantaged by their fab, which was becoming rather “outdated”. HP approached them with a deal to use their newer fabs. This proved advantageous for both, and soon HP’s fabs were open to anyone. Weitek also worked with HP on the design of their latest PA-RISC design and sold their own version known as the RISC 8200, which was sold as an embedded design and had some use in laser printers.

In the late 1980s Weitek saw a new opportunity and started developing frame buffers for Sun Microsystems workstations. In the early 1990s they also introduced the SPARC POWER µP (as in “power-up”, and technically referred to as WTL 8601), a pin-compatible version of the SPARC processor. The µP could be dropped into existing SPARCstation 2 and SPARCstation IPX workstations and ran at 80 MHz, double the clock speed of the CPUs it replaced. The 8701 ran twice as fast internally, providing a boost of about 50–60 % in overall speed, due to the bus not getting any faster. However they did not pursue this concept with later generations of SPARC processors.

Weitek turned their frame-buffer experience to the PC market in the early 90s and introduced a series of SVGA multimedia chipsets known as the “POWER” systems. Consisting of two chips, one drawing the graphics known as the P9000 and another handling the output, the VideoPower 5x86, the POWER series was used in a number of third-party designs based on the VESA Local Bus standard. The P9001 moved to PCI and became fairly popular in 1994, known as the Viper in designs from Diamond and Orchid. The final generation, the P9100, combined the P9001 and 5286 into a single chip. Weitek adapters were fairly successful in the early days of the 486 market, but fell from use when less expensive systems were introduced by a host of new players in the mid-1990s.

Weitek attempted to re-enter at the low-end market with their W464 (486) and W564 (P5) systems, which used the host machine's RAM as the frame buffer to lower costs. These were one of the reasons the company was purchased by Rockwell shortly after they shipped.

External links

• Weitek - the original home page, cached but largely un-functional
• Weitek Sparc2 Upgrade Chip
• Weitek chip images and information on cpu-collection.de