HM538253B Datasheet, PDF (1/56 Pages) Elpida Memory – 2 M VRAM (256-kword x 8-bit) Hyper Page Mode (HM538254B)

HM538253B Series
HM538254B Series
2 M VRAM (256-kword × 8-bit)
Hyper Page Mode (HM538254B)
E0163H10 (Ver. 1.0)
(Previous ADE-203-264A/265 (Z))
Jul. 6, 2001 (K)
Description
The HM538253B/HM538254B is a 2-Mbit multiport video RAM equipped with a 256-kword × 8-bit dynamic
RAM and a 512-word × 8-bit SAM (full-sized SAM). Its RAM and SAM operate independently and
asynchronously. The HM538253B/HM538254B is upwardly compatible with the HM534253B/HM538123B
except that the pseudo-write-transfer cycle is replaced with masked-write-transfer cycle, which has been
approved by JEDEC. Furthermore, several new features have been added to the HM538253B/HM538254B
which do not conflict with the conventional features. The stopping column feature realizes allows greater
flexibility for split SAM register lengths. Persistent mask is also installed according to the TMS34020
features. The HM538254B has Hyper page mode which enables fast page cycle.
Features
• Multiport organization:RAM and SAM can operate asynchronously and simultaneously:
 RAM: 256-kword × 8-bit
 SAM: 512-word × 8-bit
• Access time
 RAM: 70 ns/80 ns/100 ns max
 SAM: 20 ns/23 ns/25 ns max
• Cycle time
 RAM: 130 ns/150 ns/180 ns min
 SAM: 25 ns/28 ns/30 ns min
• Low power
 Active RAM: 605 mW/550 mW/495 mW
SAM: 358 mW/330 mW/303 mW
 Standby 38.5 mW max
• Masked-write-transfer cycle capability
• Stopping column feature capability
• Persistent mask capability
Elpida Memory, Inc. is a joint venture DRAM company of NEC Corporation and Hitachi, Ltd.