IBM prepares synch SRAM entries

Electronic News, June 6, 1994 by Walter Andrews

EAST FISHKILL, N.Y. -- IBM today enters the synchronous SRAM market with a 1- Megabit family of 12 devices having access speeds around 10 nanoseconds or less and targeted at the market for secondary cache memory needed for PCs and other systems using the higher-speed micro-processors such as Intel's Pentium and the PowerPC.

Roger Verhelst, SRAM product manager for the IBM Microelectronics Division, said quickly-rising speeds of the new MPUs is creating a "dramatic" rise in demand for synchronous SRAMs with access speeds in the 10ns-or-less region to handle data from the main DRAM memories, and the MPU speeds are rising at a greater rate than memories. "That widening gap will, in my opinion, have to be filled with cache. Right now there's a very tight supply. Everyone's clamoring for 9ns parts for Pentium machines. There seems to be a dramatic shortage of them, which leads me to believe that the rest of the guys may be having trouble making them."

The executive noted Micron Semiconductor, Motorola and other companies have announced similar parts and may be in the market earlier. IBM will sample in 3Q94 and move into volume production in 4Q94, he said.

"We're all basically competing for the same marketplace. We're not trying to make our part different. We're trying to satisfy the L2 (secondary level cache) demand that's out there," he said, adding that any MPU with speeds of 66MHz or higher needs a high-performance secondary cache memory. IBM is currently holding discussions "with the major PC manufacturers" but no commitments have been made as yet, Mr. Verhelst said.

Mr. Verhelst said IBM's announcement of the family is an "initial offering" and IBM plans to have higher-performance and higher-density SRAMs by mid-1995 to meet the demand of MPUs of 100MHz speeds and higher. The devices introduced today are aimed at mid-range to high-performance PCs of 60MHz and faster costing more than $2,000 as well as servers and workstations.

IBM gave what it called "a representative price" of $58 each in quantities of 1,000 pieces. Mr. Verhelst initially said he would supply more specific prices from IBM's price list but later backed off, saying the prices would be announced as the parts moved into production. "We will try to maintain our prices in a competitive posture," he said.

The 1-Meg SRAMs IBM is introducing today have flow-through access times of 8, 9, 10 and 12ns with two organizations: 64K words by 18 bits and 32K words by 36 bits. Among the 12-member family will be parts having pipeline-access speeds of 4 and 5ns, which Mr. Verhelst said will provide higher-speed transition to the planned 1995 enhancements for 100MHz to 150MHz computer systems now being planned.

Amid the 12-piece line, IBM is offering burst-mode versions to support functions specific to the Pentium and PowerPC MPUs, lessening system complexity and enhancing performance. The family includes single-clock, read/write operation, self-timed write operation and compatibility with low-voltage, transistor-transistor (LVTTL) I/O interfaces.

Manufactured using IBM's 0.5-micron CMOS process for low-power consumption, the devices will be offered in "industry-standard" 100-pin thin quad flat pack (TQFP), 52-pin plastic leaded chip carrier (PLCC) and 7 x 17 ball grid array (BGA) packages.

"Our first shipments will be limited to 100 MHz... Toward the end of the year and the early part of next year, we'll migrate that from 100MHz to 167MHz" (the maximum operating frequency seen for the initial family), Mr. Verhelst said. He said the SRAMs will be both 3V and 5V compliant and will work with either chipsets in either voltage.

Mr. Verhelst said the IBM family will be pin-compatible with Micron Semiconductor's 100-pin part and Motorola's 52-pin device. "The three of us have compared notes and the BGA is going to be JEDEC standard."

Earlier this year (EN, Jan. 24, May 2) Micron Semiconductor began sampling of 32K by 36, 64K by 18 and 32K by 32 SRAMs with production (in a 0.35-micron CMOS process) planned to start next month for the first two. Volume production of the latter part will be "probably in December," according to Jerry Johnson, Micron's semiconductor marketing manger.

He said production of the 32K by 32 part is later because "we're doing a shrink" of a current part "to make ... the much lower-cost part that the market's looking for." Initially, the first two products were priced at $40 each in sample quantities of 100 but have recently been reduced to $35, which is now the price for all three organizations, which encompass a family of 24 parts, Mr. Johnson said. "That's our sample prices."

"When we go into production, the prices vary depending on speed, grade and package and organization," Mr. Johnson said. "It's hard to say," the executive said, if the production prices will be less than the sample prices. "We'll start out with what we think is a reasonable price and then it depends on market demand where that price goes."

Sharp Electronics and NEC Electronics have said they will provide devices that are pin- and function-compatible with those of Micron.