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White Electronic Designs Corporation (602) 437-1520 www.whiteedc.com
WEDPND8M72S-XBX
May 2002 Rev. 0
The 64MByte (512Mb) DDR SDRAM is a high-speed CMOS,
dynamic random-access, memory using 5 chips containing
134,217,728 bits. Each chip is internally configured as a
quad-bank DRAM. Each of the chip’s 33,554,432-bit banks
is organized as 4,096 rows by 512 columns by 16 bits.
The 64 MB DDR SDRAM uses a double data rate architecture
to achieve high-speed operation. The double data rate ar-
chitecture is essentially a 2
n-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
64MB DDR SDRAM effectively consists of a single 2
n-bit wide,
one-clock-cycle data tansfer at the internal DRAM core and
two corresponding
n-bit wide, one-half-clock-cycle data
transfers at the I/O pins.
A bidirectional data strobe (DQS) is transmitted externally, along
with data, for use in data capture at the receiver. DQS is a
8Mx72 DDR SDRAM
n High Frequency = 200, 250, 266MHz
n Package:
219 Plastic Ball Grid Array (PBGA), 32 x 25mm
n 2.5V ±0.2V core power supply
n 2.5V I/O (SSTL_2 compatible)
n Differential clock inputs (CLK and CLK)
n Commands entered on each positive CLK edge
n Internal pipelined double-data-rate (DDR) architecture;
two data accesses per clock cycle
n Programmable Burst length: 2,4 or 8
n Bidirectional data strobe (DQS) transmitted/received
with data, i.e., source-synchronous data capture (one
per byte)
n DQS edge-aligned with data for READs; center-aligned
with data for WRITEs
n DLL to align DQ and DQS transitions with CLK
n Four internal banks for concurrent operation
n Two data mask (DM) pins for masking write data
n Programmable IOL/IOH option
n Auto precharge option
n Auto Refresh and Self Refresh Modes
n Commercial, Industrial and Military Temperature Ranges
n Organized as 8M x 72
n Weight: WEDPND8M72S-XBX - 2.5 grams typical
FEATURES
Advanced*
n 40% SPACE SAVINGS
n Reduced part count
n Reduced I/O count
34% I/O Reduction
n Reduced trace lengths for lower parasitic capacitance
n Suitable for hi-reliability applications
n Laminate interposer for optimum TCE match
n Upgradeable to 16M x 72 density (contact factory for
information)
* This data sheet describes a product that is developmental, is not qualified
and is subject to change or cancellation without notice.
GENERAL DESCRIPTION
BENEFITS
25
32
66
TSOP
66
TSOP
66
TSOP
66
TSOP
66
TSOP
11.9
22.3
Monolithic Solution
Actual Size
WEDPND8M72S-XBX
S
A
V
I
N
G
S
Area
I/O
Count
5 x 265mm2 = 1328mm2
5 x 66 pins = 330 pins
800mm2
40%
219 Balls
34%
WEDPND8M72S-XBX