MT9HTF6472AY-667D4 Micron Technology Inc, MT9HTF6472AY-667D4 Datasheet - Page 10

• Manufacturer Part Number: MT9HTF6472AY-667D4
• Description: MODULE DDR2 512MB 240-DIMM
• Manufacturer: Micron Technology Inc

Specifications of MT9HTF6472AY-667D4

• Memory Type: DDR2 SDRAM
• Memory Size: 512MB
• Package / Case: 240-DIMM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Speed: -
• Other names: 557-1303; MT9HTF6472AY-667D4

General Description
Serial Presence-Detect Operation
pdf: 09005aef80e6f860, source: 09005aef80e5b799
HTF9C32_64_128x72AG_2.fm - Rev. C 6/05 EN
The MT9HTF3272A, MT9HTF6472A, and MT9HTF12872A DDR2 SDRAM modules are
high-speed, CMOS, dynamic random-access 256MB, 512MB, and 1GB memory modules
organized in x64 configuration. DDR2 SDRAM modules use internally configured quad-
bank (256MB, 512MB) or eight-bank (1GB) DDR2 SDRAM devices.
DDR2 SDRAM modules use double data rate architecture to achieve high-speed opera-
tion. The double data rate architecture is essentially a 4n-prefetch architecture with an
interface designed to transfer two data words per clock cycle at the I/O pins. A single
read or write access for the DDR2 SDRAM module effectively consists of a single 4n-bit-
wide, one-clock-cycle data transfer at the internal DRAM core and four corresponding
n-bit-wide, one-half-clock-cycle data transfers at the I/O pins.
A bidirectional data strobe (DQS, DQS#) is transmitted externally, along with data, for
use in data capture at the receiver. DQS is a strobe transmitted by the DDR2 SDRAM
device during READs and by the memory controller during WRITEs. DQS is edge-
aligned with data for READs and center-aligned with data for WRITEs.
DDR2 SDRAM modules operate from a differential clock (CK and CK#); the crossing of
CK going HIGH and CK# going LOW will be referred to as the positive edge of CK. Com-
mands (address and control signals) are registered at every positive edge of CK. Input
data is registered on both edges of DQS, and output data is referenced to both edges of
DQS, as well as to both edges of CK.
Read and write accesses to DDR2 SDRAM modules are burst-oriented; accesses start at a
selected location and continue for a programmed number of locations in a programmed
sequence. Accesses begin with the registration of an ACTIVE command, which is then
followed by a READ or WRITE command. The address bits registered coincident with the
ACTIVE command are used to select the device bank and row to be accessed. The
address bits registered coincident with the READ or WRITE command are used to select
the device bank and the starting column location for the burst access.
DDR2 SDRAM modules provide for programmable read or write burst lengths of four or
eight locations. DDR2 SDRAM devices support interrupting a burst read of eight with
another read, or a burst write of eight with another write. An auto precharge function
may be enabled to provide a self-timed row precharge that is initiated at the end of the
burst access.
The pipelined, multibank architecture of DDR2 SDRAM devices allows for concurrent
operation, thereby providing high, effective bandwidth by hiding row precharge and
activation time.
A self refresh mode is provided, along with a power-saving power-down mode.
All inputs are compatible with the JEDEC standard for SSTL_18. All full drive-strength
outputs are SSTL_18-compatible.
DDR2 SDRAM modules incorporate serial presence-detect (SPD). The SPD function is
implemented using a 2,048-bit EEPROM. This nonvolatile storage device contains 256
bytes. The first 128 bytes can be programmed by Micron to identify the module type and
various SDRAM organizations and timing parameters. The remaining 128 bytes of stor-
age are available for use by the customer. System READ/WRITE operations between the
master (system logic) and the slave EEPROM device occur via a standard I
the DIMM’s SCL (clock) and SDA (data) signals, together with SA (2:0), which provide
eight unique DIMM/EEPROM addresses. Write protect (WP) is tied to ground on the
module, permanently disabling hardware write protect.
256MB, 512MB, 1GB (x72, SR, ECC) 240-Pin DDR2 SDRAM UDIMM
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Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2003, 2004, 2005 Micron Technology, Inc. All rights reserved.
General Description
2
C bus using