GS8662S08/09/18/36E-250/200/167
165-Bump BGA
Commercial Temp
Industrial Temp
Features
• Simultaneous Read and Write SigmaSIO™ DDR-II Interface
• JEDEC-standard pinout and package
• Dual Double Data Rate interface
• Byte Write controls sampled at data-in time
• DLL circuitry for wide output data valid window and future
frequency scaling
• Burst of 2 Read and Write
• 1.8 V +100/–100 mV core power supply
• 1.5 V or 1.8 V HSTL Interface
• Pipelined read operation
• Fully coherent read and write pipelines
• ZQ mode pin for programmable output drive strength
• IEEE 1149.1 JTAG-compliant Boundary Scan
• Pin-compatible with future 144Mb devices
• 165-bump, 15 mm x 17 mm, 1 mm bump pitch BGA package
• RoHS-compliant 165-bump BGA package available
72Mb Burst of 2
SigmaSIO™ DDR-II SRAM
250 MHz–167 MHz
1.8 V V
DD
1.8 V and 1.5 V I/O
me
nd
ed
for
GS8662S08/09/18/36 are built in compliance with the
SigmaSIO DDR-II SRAM pinout standard for Separate I/O
synchronous SRAMs. They are 75,497,472-bit (72Mb)
SRAMs. These are the first in a family of wide, very low
voltage HSTL I/O SRAMs designed to operate at the speeds
needed to implement economical high performance
networking systems.
Ne
w
Parameter Synopsis
-250
4.0 ns
-200
5.0 ns
0.45 ns
-167
6.0 ns
0.5 ns
tKHKH
tKHQV
0.45 ns
Rev: 1.07 8/2012
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SigmaSIO™ DDR-II Family Overview
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Clocking and Addressing Schemes
A Burst of 2 SigmaSIO DDR-II SRAM is a synchronous
device. It employs dual input register clock inputs, K and K.
The device also allows the user to manipulate the output
register clock input quasi independently with dual output
register clock inputs, C and C. If the C clocks are tied high, the
K clocks are routed internally to fire the output registers
instead. Each Burst of 2 SigmaSIO DDR-II SRAM also
supplies Echo Clock outputs, CQ and CQ, which are
synchronized with read data output. When used in a source
synchronous clocking scheme, the Echo Clock outputs can be
used to fire input registers at the data’s destination.
Each internal read and write operation in a SigmaSIO DDR-II
B2 RAM is two times wider than the device I/O bus. An input
data bus de-multiplexer is used to accumulate incoming data
before it is simultaneously written to the memory array. An
output data multiplexer is used to capture the data produced
from a single memory array read and then route it to the
appropriate output drivers as needed. Therefore, the address
field of a SigmaSIO DDR-II B2 is always one address pin less
than the advertised index depth (e.g., the 8M x 8 has a 4M
addressable index).
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
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© 2005, GSI Technology