
Preliminary
GS8662Q08/09/18/36E-300/250/200/167
72Mb SigmaQuad-II
Burst of 2 SRAM
300 MHz–167 MHz 
1.8 V V
DD
1.8 V and 1.5 V I/O
165-Bump BGA
Commercial Temp
Industrial Temp
Rev:  1.01  9/2005
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
1/35
 2005, GSI Technology
Features
 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 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 pin for programmable output drive strength
 IEEE 1149.1 JTAG-compliant Boundary Scan
 Pin-compatible with present 9Mb, 18Mb, and 36Mb and 
future 144Mb devices 
 165-bump, 15 mm x 17 mm, 1 mm bump pitch BGA package
 RoHS-compliant 165-bump BGA package available
SigmaQuad
 Family Overview
The GSQ8662Q08/09/18/36E   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 GSQ8662Q08/09/18/36E  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. 
Clocking and Addressing Schemes
The GSQ8662Q08/09/18/36E 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. 
Because Separate I/O SigmaQuad-II B2
RAMs always transfer 
data in two packets, A0 is internally set to 0 for the first read or 
write transfer, and automatically incremented by 1 for the next 
transfer. Because the LSB is tied off internally, the address 
field of a SigmaQuad-II B2 
RAM is always one address pin 
less than the advertised index depth (e.g., the 4M x 18 has a 
2048K addressable index).
Parameter Synopsis
-300
-250
-200
-167
tKHKH
3.3 ns
4.0 ns
5.0 ns
6.0 ns
tKHQV
0.45 ns
0.45 ns
0.45 ns
0.5 ns
165-Bump, 15 mm x 17 mm BGA
1 mm Bump Pitch, 11 x 15 Bump Array
Bottom View