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News Release

January 26, 1998

Hitachi Releases the Industry's First 128M Bit EDO and Synchronous DRAM Products

- Achieved using two 64M bit DRAM chips stacked in a standard 400-mil TSOP package -

Hitachi, Ltd. today announced the release of four new memory product series for main and expansion memory in PCs and engineering workstations. Two of these series, the HM5113805TD (x 8 bits, 4k refresh) and the HM5113165TD (x16 bits, 4k refresh), are 128M bit EDO DRAMs that use a stacking technology and provide access times of 60 ns, and the other two series, the HM 5212805TD (x 8 bits) and the HM5212165TD (x16 bits), are128M bit synchronous DRAMs that use the same stacking technology and support a PC 66MHz memory bus. The EDO products will be available in sample quantities at the end of January 1998, and the SDRAM products will be available in sample quantities in February 1998.

These products each use two Hitachi 64M bit DRAM chips (either EDO or synchronous) molded together in a standard package using Hitachi's stacking technology. The EDO product uses the same package as earlier 64M bit DRAMs, and the SDRAM product uses the same package (a 400-mil 54-pin TSOP II package) will be used for 128M bit SDRAMs and 256M bit SDRAMs.

The trends towards further miniaturization and increased memory capacities in PCs are accelerating. For example, while most notebook PCs currently have 32M bytes of main memory, it is expected that 64M bytes will become standard by the middle of 1998. At the same time, there are strong demands for further miniaturization in these products to provide improved portability, and thus it is simply not possible to provide more space for memory chips in such systems. In particular, while four 64M bit DRAMs are now used to provide 32M bytes of onboard memory, it would be difficult to expand this to 64M bytes. Hitachi developed the 128M bit DRAM to allow larger memory capacities to be achieved in such limited spaces.

In the EDO products, the HM5113805TD series provides an x 8-bit structure by stacking two x 4-bit 64M byte EDO DRAM chips within the package and molding them together into a single unit. Similarly, the HM5113165TD series provides a x16-bit structure by stacking two x 8-bit 64M byte EDO DRAM chips within the package and molding them together. In the same way, in the SDRAM products, the HM 5212805TD series and HM5212165TD series are formed using two 64M bit synchronous DRAM chips; using two x4-bit chips to form an x8-bit structure and two x8-bit chips to form a x16-bit structure, respectively.

Since these stacked products all use the same 400-mil TSOP-II package as 64M bit products, they can easily replace 64M bit products. Thus these products can double memory capacities without increasing the mounting space required. 8k refresh versions of the EDO products are available. It is planned to expand the product line up.

Application Product Examples

  • Onboard memory for notebook personal computers
  • Main and expansion memory in personal computers and engineering workstations

Pricing in Japan

  • 128M bit DRAM (EDO)
Product NameStructureRefresh periodSample price (Yen)
HM5113805TD-616M x 84k/64ms7,500
HM5113165TD-68M x 164k/64ms7,500
HM5112805TD-616M x 88k/64ms7,500
HM5112165TD-68M x 168k/64ms7,500

  • 128M bit SDRAM
Product NameStructureRefresh periodSample price (Yen)
HM5212805TD-104M x 8 x 4 banks4k/64ms10,000
HM5212165TD-102M x 16 x 4 banks 4k/64ms10,000

Supplementary Documentation

1) EDO DRAM

  • x8 bit structure
HM5113805TD series (4k refresh version) and HM5112805TD series (8k refresh version)

HM5113805TD seriesHM5112805TD series
Product structure16,777,216-word x 8-bit Dynamic RAM
Power-supply voltage3.3-V single-voltage power supply (+/-0.3 V)
Access time60ns (max)
Power dissipation
Operating: 792 mW
(maximum)
Operating: 720 mW
(maximum)
Standby: 3.6 mW (maximum)Standby: 3.6 mW (maximum)
(CMOS interface)(CMOS interface)
High-speed access modeEDO page mode
Refresh format
4,096cycle/64ms8,192cycle/64ms

RAS-only refresh
CAS-before-RAS refresh
Hidden refresh
Package400-mil 32-pin plastic TSOP II (TTP - 32DE)

  • x 16-bit
HM5113165TD series (4k refresh version) and HM5112165TD series (8k refresh version)

HM5113165TD seriesHM5112165TD series
Product structure8,388,608-word x 16-bit Dynamic RAM
Power-supply voltage3.3-V single-voltage power supply (+/-0.3 V)
Access time60ns (max)
Power dissipation
Operating: 828 mW
(maximum)
Operating: 756 mW
(maximum)
Standby: 3.6 mW (maximum)Standby: 3.6 mW (maximum)
(CMOS interface)(CMOS interface)
High-speed access modeEDO page mode
Refresh format
4,096cycle/64ms8,192cycle/64ms

RAS-only refresh
CAS-before-RAS refresh
Hidden refresh
Package400-mil 50-pin plastic TSOP II (TTP - 50DC)

2) SDRAM

  • x8 bit structure
HM521805TD series
Product structure4,194,304-word x 8-bit x 4-bank Synchronous Dynamic RAM
Power-supply voltage3.3-V single-voltage power supply (+/-0.3 V)
Operating clock frequencyPC 66MHz bus
Type and functionsLVTTL interface
Single RAS pulse system
The four banks can be operated simultaneously or independently.
Supports both burst read/write and burst read/single write operation.
Burst length: Can be set to 1, 2, 4, 8 or full page
Supports two types of burst sequence (sequential and interleaved)
Supports sequential burst and burst stop operations in full page burst mode.
The CAS latency can be set to 2 or 3.
Refresh format4,096cycle/64ms

Auto refresh
Self refresh
Package400-mil 54-pin plastic TSOP II

  • x16 bit structure
HM5212165TD series
Product structure2,097,152-word x 16-bit x 4-bank Synchronous Dynamic RAM
Power-supply voltage3.3-V single-voltage power supply (+/-0.3 V)
Operating clock frequencyPC 66MHz bus
Type and functionsLVTTL interface
Single RAS pulse system
The four banks can be operated simultaneously or independently.
Supports both burst read/write and burst read/single write operation.
Burst length: Can be set to 1, 2, 4, 8 or full page
Supports two types of burst sequence (sequential and interleaved)
Supports sequential burst and burst stop operations in full page burst mode.
The CAS latency can be set to 2 or 3.
Refresh format4,096cycle/64ms

Auto refresh
Self refresh
Package400-mil 54-pin plastic TSOP II


WRITTEN BY Secretary's Office
All Rights Reserved, Copyright (C) 1998, Hitachi, Ltd.