GS8662D08/09/18/36E-250/200/167
72Mb SigmaQuad-II
Burst of 4 SRAM
165-Bump BGA
Commercial Temp
Industrial Temp
250 MHz–167 MHz
1.8 V VDD
1.8 V and 1.5 V I/O
Clocking and Addressing Schemes
• Simultaneous Read and Write SigmaQuad™ Interface
• JEDEC-standard pinout and package
• Dual Double Data Rate interface
• Byte Write controls sampled at data-in time
• Burst of 4 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 pin for programmable output drive strength
• IEEE 1149.1 JTAG-compliant Boundary Scan
• Pin-compatible with present 9Mb, 18Mb, and 36Mb and
144Mb devices
• 165-bump, 15 mm x 17 mm, 1 mm bump pitch BGA package
• RoHS-compliant 165-bump BGA package available
The GS8662D08/09/18/36E SigmaQuad-II SRAMs are
synchronous devices. They employ two input register clock
inputs, K and K. K and K are independent single-ended clock
inputs, not differential inputs to a single differential clock input
buffer. The device also allows the user to manipulate the
output register clock inputs quasi independently with the C and
C clock inputs. C and C are also independent single-ended
clock inputs, not differential inputs. If the C clocks are tied
high, the K clocks are routed internally to fire the output
registers instead.
Each internal read and write operation in a SigmaQuad-II B4
RAM is four 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 SigmaQuad-II B4 RAM is always two address pins
less than the advertised index depth (e.g., the 8M x 8 has a 2M
addressable index).
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The GS8662D08/09/18/36E are built in compliance with the
SigmaQuad-II SRAM pinout standard for Separate I/O
synchronous SRAMs. They are 75,497,472-bit (72Mb)
SRAMs. The GS8662D08/09/18/36E SigmaQuad SRAMs
are just one element in a family of low power, low voltage
HSTL I/O SRAMs designed to operate at the speeds needed to
implement economical high performance networking systems.
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SigmaQuad™ Family Overview
ct
Features
.
Parameter Synopsis
-200
-167
tKHKH
4.0 ns
5.0 ns
6.0 ns
tKHQV
0.45 ns
0.45 ns
0.50 ns
No
t
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co
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-250
Rev: 1.10 8/2012
1/35
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2005, GSI Technology
