Data Sheet
64Mbit – High Speed SDRAM
8Mx8, 4Mx16 HSDRAM
Description
The Enhanced Memory Systems SM3603 and SM3604 High-
Speed SDRAM (HSDRAM) devices are high performance
versions of the proposed JEDEC PC-133 SDRAM. While
compatible with standard SDRAM, they provide the faster
clock access time (4.6 ns), shorter random access latency
(34.6 ns), and fast bank cycle time (52.5 ns) needed to
improve system stability, capacity, and performance in
systems operating at 133 MHz and higher bus speeds. The
HSDRAM is ideal for any high performance system
including PCs, workstations, servers, communications
switches, DSP systems, 3-D graphics, and embedded
computers.
Features
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JEDEC Standard PC-133 SDRAM
Fast 4.6 ns CL3 Clock Access Time
Fast 13.75 ns CL1 Clock Access Time (-7.5F)
Low Latency Operation (3:2:2 @ 133 MHz)
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CAS Latency = 3
•
RAS to CAS Delay = 2
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Precharge Delay = 2
Fast Random Access Time (34.6 ns)
Fast Random Cycle time (52.5 ns)
Programmable Burst length (1, 2, 4, 8, full page)
Programmable CAS Latency (1, 2, 3)
Low Power suspend, Self Refresh, and Power
Down Modes Supported
4K Refresh / 64 ms
Single 3.3V
±
5% Power Supply
54-pin TSOP-II (0.8mm pin pitch)
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Block Diagram (4Mx16 shown)
ADDRESS BUFFERS
ROW DECODER
BA1
BA0
A(11:0)
BANK A
4K rows x
256 col x
16 bits
BANK B
4K rows x
256 col x
16 bits
BANK C
4K rows x
256 col x
16 bits
BANK D
4K rows x
256 col x
16 bits
SENSE AMPLIFIERS
COLUMN DECODER
SENSE AMPLIFIERS
COLUMN DECODER
SENSE AMPLIFIERS
COLUMN DECODER
SENSE AMPLIFIERS
COLUMN DECODER
Data I/O Buffers
CLK
CKE
/CS
/RAS
/CAS
/WE
UDQM,
LDQM
DQ(15:0)
COMMAND
DECODER
and
TIMING
GENERATOR
Enhanced Memory Systems Inc., 1850 Ramtron Dr., Colo Spgs, CO 80921
PHONE: (800) 545-DRAM; FAX: (719) 488-9095;
http://www.edram.com
1999 Enhanced Memory Systems. All rights reserved.
The information contained herein is subject to change without notice.
Revision 1.1
Page 1 of 10
RAMTRON [ RAMTRON INTERNATIONAL CORPORATION ]
