News and New Products

IBM, Sony, Toshiba Present Cell

By Richard Ball -- Electronics Weekly, 2/8/2005

At the International Solid State Circuits Conference (ISSCC) today, the Cell processor developed jointly by IBM, Sony and Toshiba was unveiled.

The multi-core processor claims supercomputer-like levels of performance with clock speeds in excess of 4GHz.

A first prototype of the device expected to power the PlayStation 3 has a 221mm² die, uses 234 million transistors and is made using 90nm process technology.

The version of Cell announced today contains eight 64-bit floating point processors, referred to as synergistic processor elements (SPE). Along side these is a 64-bit Power processor capable of running two threads.

SPEs take 128-bit operands, split into four 32-bit words. Up to 128 operands can be stored in the register file.

Each 2.5x5.81mm SPE can issue two instructions per cycle to seven execution units using two pipelines. There is no out of order execution.

Connecting up the processing units is the element interconnect bus (EIB), comprising four 128-bit rings and a 64-bit tag running at half the processor clock.

The busses connect to the SPEs through local memory, 256Kbyte for each SPE. The developers have tested the memories to 5.4GHz at 1.3V and 52°C.

There are 15 separate power domains on the chip. Ten digital thermometers monitor the chip at various points to alert the system of thermal problems.

The companies expect to begin production of Cell processors at IBM's 300mm plant in New York and Sony's Nagasaki fab later this year.

Cell-based products will be used in devices ranging from digital televisions to home servers to supercomputers, they said.

Electronics Weekly is the London-based sister publication of Electronic News.