
DM2203/2213 Mutibank EDOEDRAM
512Kbx 8 EnhancedDynamc RAM
ProductSpecifcaton
1996 Enhanced Memory Systems Inc.
1850 Ramtron Drive, Colorado Springs, CO
Telephone
(800) 545-DRAM;
Fax
(719) 488-9095; http://wwwcsn.net/ramtron/enhanced
80921
38-2105-001
The information contained herein is subject to change wthout notice.
Enhanced reserves the right to change or discontinue this product wthout notice.
Features
I
8Kbit SRAMCache Memory for 12ns RandomReads Wthin Four
Active Pages (Multibank Cache)
I
Fast 4Mbit DRAMArray for 30ns Access to Any NewPage
I
Write Posting Register for 12ns RandomWrites and Burst Writes
Wthin a Page (Hit or Mss)
I
5ns Output Enable Access Time Allows Fast Interleaving
I
256-byte Wde DRAMto SRAMBus for 14.2 Ggabytes/Sec Cache Fill
I
On-chip Cache Hit/Mss Comparators Maintain Cache Coherency
Wthout the Need for External Cache Control
I
A Hit Pin Outputs Status of On-chip Page Hit/Mss Comparators to
Simplify Control
I
Output Latch Enable Allows Extended Data Output (EDO) For
Faster SystemOperation
I
Hidden Precharge Cycles
I
Hidden Refresh Cycles
I
Write-per-bit Option (DM2213) for Parity and Video Applications
I
Extended 64ms Refresh Period for LowStandby Power
I
Standard CMOS/TTL Compatible I/OLevels and +5 Volt Supply
I
LowProfile 300-Ml 44-Pin TSOP-II Package
I
Industrial Temperature Range Option
Description
The Enhanced Memory Systems 4Mb EDRAMcombines raw
speed wth innovative architecture to offer the optimumcost-
performance solution for high performance local or main memory in
computer and embedded control systems. In most high speed
applications, zero-wait-state operation can be achieved wthout
secondary SRAMcache for systemclock speeds of up to 83MHz
wthout interleaving or 132MHz wth two-way interleaving. The
EDRAMoutperforms conventional SRAMcache plus DRAMor
synchronous DRAMmemory systems by mnimzing wait states on
Architectural simlarity wth JEDEC DRAMs allows a single memory
controller design to support either slowJEDEC DRAMs or high speed
EDRAMs. A systemdesigned in this manner can provide a simple
upgrade path to higher systemperformance.
The 512K x 8 EDRAMhas the same control and address interface
as Enhanceds 4Mx 1 and 1Mx 4 EDRAMproducts so that EDRAMs
of different organizations can be supported wth the same controller
design. The 512K x 8 EDRAMimplements the followng additional
features which can be supported on newdesigns:
I
A controllable output latch provides an extended data out (EDO)
mode.
I
Cache size is increased from2Kbits to 8Kbits. The 8Kbit cache is
organized as four 256 x 8 direct mapped rowregisters.
I
A hit pin is provided to tell the memory controller when a hit
occurs to one of the on-chip cache rowregisters.
Archtecture
The EDRAMarchitecturehas a simple integrated SRAMcache
which allows it to operate much like a page mode or static column
DRAM
/CAL
A
0
- A
10
W/R
/F
/RE
V
V
Sense Amps
& Column Write Select
Column Decoder
Row
Address
Latch
CC
SS
A
0
- A
9
4 - 256 X 8 Cache Pages
(Row Registers)
Memory
Array
(2048 X 256 X 8)
A
0
- A
7
/G
/S
/WE
DQ - DQ
7
Column
Address
Latch
4 - 9 Bit
Comparators
I/O
Control
and
Data
Latches
Refresh
Counter
R
Row Adress
and
Refresh
Control
/HIT
4 - Last Row
Read Address
Latches
QLE
Functional Dagram
1
2
3
4
5
6
7
9
10
11
12
13
42
41
40
39
38
37
36
34
33
32
31
30
29
28
27
26
25
24
23
14
15
16
17
18
19
20
21
22
V
8
35
43
44
CC
/F
V
SS
DQ
0
V
CC
DQ
1
DQ
2
V
SS
DQ
3
QLE
V
CC
/G
DQ
4
V
SS
DQ
5
DQ
6
V
CC
DQ
7
V
SS
NC
NC
V
CC
V
SS
W/R
/S
A
10
A
9
A
8
A
7
A
6
A
5
A
4
V
SS
/RE
/CAL
V
CC
A
3
A
2
A
1
A
0
/WE
NC
/HIT
V
SS
Pin Configuration
Enhanced
Memory Systems Inc.