GS8662Q20/38CGD-500/450/400
500 MHz–400 MHz
165-Bump BGA
Commercial Temp
Industrial Temp
TM
72Mb SigmaQuad-II+
Burst of 2 SRAM
1.8 V V
DD
1.8 V and 1.5 V I/O
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.
Features
• 2.5 clock Latency
• Simultaneous Read and Write SigmaQuad™ Interface
• JEDEC-standard pinout and package
• Dual Double Data Rate interface
• Byte Write controls sampled at data-in time
• On-Die Termination (ODT) on Data (D), Byte Write (BW),
and Clock (K, K) inputs
• Burst of 2 Read and Write
• 1.8 V +100/–100 mV core power supply
• 1.5 V or 1.8 V HSTL Interface
Clocking and Addressing Schemes
The GS8662Q20/38CGD 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.
• Pipelined read operation
• Fully coherent read and write pipelines
• ZQ pin for programmable output drive strength
• Data Valid Pin (QVLD) Support
• IEEE 1149.1 JTAG-compliant Boundary Scan
• RoHS-compliant 165-bump BGA package
Each internal read and write operation in a SigmaQuad-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
SigmaQuad-II+ B2 RAM is always one address pin less than
the advertised index depth (e.g., the 4M x 18 has an 2M
addressable index).
SigmaQuad™ Family Overview
The GS8662Q20/38CGD 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 GS8662Q20/38CGD SigmaQuad SRAMs are
Parameter Synopsis
-500
2.0 ns
0.45 ns
-450
2.2 ns
0.45 ns
-400
2.5 ns
0.45 ns
tKHKH
tKHQV
Rev: 1.01 9/2019
1/24
© 2019, GSI Technology
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.