GS8662DT20/38CGD-633/550/500
633 MHz–500 MHz
165-Bump BGA
Commercial Temp
Industrial Temp
72Mb SigmaQuad-II+
Burst of 4 SRAM
1.8 V V
DD
1.8 V or 1.5 V I/O
Features
Clocking and Addressing Schemes
• 2.5 Clock Latency
The GS8662DT20/38CGD 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.
• 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
• Dual-Range On-Die Termination (ODT) on Data (D), Byte
Write (BW), and Clock (K, K) intputs
• 1.8 V +100/–100 mV core power supply
• 1.5 V or 1.8 V HSTL Interface
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 4M x 18 has a
1M addressable index).
• 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
SigmaQuad™ Family Overview
The GS8662DT20/38CGD 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 GS8662DT20/38CGD 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.
Parameter Synopsis
-633
-550
-500
2.0 ns
0.45 ns
tKHKH
tKHQV
1.58 ns
0.45 ns
1.81 ns
0.45 ns
Rev: 1.01 9/2019
1/26
© 2019, GSI Technology
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.