Preliminary
GS8662R08/09/18/36BD-400/350/333/300/250
165-Bump BGA
Commercial Temp
Industrial Temp
Features
• Simultaneous Read and Write SigmaDDR™ Interface
• Common I/O bus
• JEDEC-standard pinout and package
• Double Data Rate interface
• Byte Write (x36, x18 and x9) and Nybble Write (x8) function
• 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 with self-timed Late Write
• 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, 36Mb and 72Mb
devices
• 165-bump, 13 mm x 15 mm, 1 mm bump pitch BGA package
• RoHS-compliant 165-bump BGA package available
72Mb SigmaDDR-II
TM
Burst of 4 SRAM
400 MHz–250 MHz
1.8 V V
DD
1.8 V and 1.5 V I/O
Bottom View
165-Bump, 13 mm x 15 mm BGA
1 mm Bump Pitch, 11 x 15 Bump Array
clock inputs, not differential inputs. If the C clocks are tied
high, the K clocks are routed internally to fire the output
registers instead.
Common I/O x36 and x18 SigmaDDR-II B4 RAMs always
transfer data in four packets. When a new address is loaded, A0
and A1 preset an internal 2 bit linear address counter. The
counter increments by 1 for each beat of a burst of four data
transfer. The counter always wraps to 00 after reaching 11, no
matter where it starts.
Common I/O x8 and x9 SigmaDDR-II B4 RAMs always
transfer data in four packets. When a new address is loaded,
the LSBs are internally set to 0 for the first read or write
transfer, and incremented by 1 for the next 3 transfers.
Because the LSBs are tied off internally, the address field of a
x8/x9 SigmaDDR-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).
SigmaDDR™ Family Overview
The GS8662R08/09/18/36BD are built in compliance with the
SigmaDDR-II SRAM pinout standard for Common I/O
synchronous SRAMs. They are 75,497,472-bit (72Mb)
SRAMs. The GS8662R08/09/18/36BD SigmaDDR-II 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 GS8662R08/09/18/36BD SigmaDDR-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
Parameter Synopsis
-400
tKHKH
tKHQV
2.5 ns
0.45 ns
-350
2.86 ns
0.45 ns
-333
3.0 ns
0.45 ns
-300
3.3 ns
0.45 ns
-250
4.0 ns
0.45 ns
Rev: 1.01 11/2010
1/37
© 2010, GSI Technology
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
京公网安备 11010802033920号
EEWORLD
