IBM11N4735BB IBM11N4645BB
IBM11N4735CB IBM11N4645CB
4M x 64/72 DRAM MODULE
50H8036
SA14-4623-02
Revised 5/96
©IBM Corporation. All rights reserved.
Use is further subject to the provisions at the end of this document.
Page 1 of 30
Features
• 168 Pin JEDEC Standard, Unbuffered 8 Byte
Dual In-line Memory Module
• 4Mx64, 4Mx72 Extended Data Out Page Mode
DIMMS
• Performance:
• All inputs and outputs are LVTTL (3.3V) compat-
ible
• Single 3.3V ± 0.3V Power Supply
• Au contacts
• Optimized for byte-write non-parity, or ECC
applications
• System Performance Benefits:
-Non buffered for increased performance
-Reduced noise (35 VSS/VCC pins)
-Byte write, byte read accesses
-Serial PDs
• Extended Data Out (EDO) Mode, Read-Modify-
Write Cycles
• Refresh Modes: RAS-Only, CBR and Hidden
Refresh
• 2048 refresh cycles distributed across 32ms
(11/11 addressing)
• 4096 refresh cycles distributed across 64ms
(12/10 addressing)
• 11/11 or 12/10 addressing (Row/Column)
• Card size: 5.25" x 1.0" x 0.354"
• DRAMS in SOJ Package
Description
IBM11N4645BB IBM11N4645CB are industry stan-
dard 168-pin 8-byte Dual In-line Memory Modules
(DIMMs) which are organized as 4Mx64 and 4Mx72
high speed memory arrays designed with EDO
DRAMs for non-parity or ECC applications. The
DIMMs use 16 (x64) or 18 (x72) 4Mx4 EDO DRAMs
in SOJ packages. The use of EDO DRAMs allows
for a reduction in Page Mode Cycle time from 40ns
(Fast Page) to 25ns for 60ns DRAM modules.
The DIMMs use serial presence detects imple-
mented via a serial EEPROM using the two pin I2C
protocol. This communication protocol uses Clock
(SCL) and Data I/O (SDA) lines to synchronously
clock data between the master (system logic) and
the slave EEPROM device (DIMM). The EEPROM
device address pins (SA0-2) are brought out to the
DIMM tabs to allow 8 unique DIMM/EEPROM
addresses. The first 128 bytes are utilized by the
DIMM manufacturer and the second 128 bytes of
serial PD data are available to the customer.
All IBM 168-pin DIMMs provide a high performance,
flexible 8-byte interface in a 5.25” long space-saving
footprint. Related products include the buffered
DIMMs (x64, x72 parity and x72 ECC Optmized) for
applications which can benefit from the on-card buff-
ers.
-60 -70
tRAC RAS Access Time 60ns 70ns
tCAC CAS Access Time 15ns 20ns
tAA Access Time From Address 30ns 35ns
tRC Cycle Time 104ns 124ns
tHPC EDO Mode Cycle Time 25ns 30ns
Card Outline
1
85 10
94 11
95 40
124 41
125 84
168
(Front)
(Back)
IBM11M4730C4M x 72 E12/10, 5.0V, Au.