GS8672D20BGE-633 Datasheet, PDF (1/30 Pages) GSI Technology – On-Chip ECC with virtually zero SER

165-Bump BGA
Commercial Temp
Industrial Temp
GS8672D20/38BE-633/550/500/450/400
72Mb SigmaQuad-II+^TM
Burst of 4 ECCRAM^TM
633 MHz–400 MHz
1.8 V V_DD
1.5 V I/O
Features
• 2.5 Clock Latency
• On-Chip ECC with virtually zero SER
• Simultaneous Read and Write SigmaQuad™ Interface
• JEDEC-standard package
• Dual Double Data Rate interface
• Byte Write Capability
• Burst of 4 Read and Write
• On-Die Termination (ODT) on Data (D), Byte Write (BW),
and Clock (K, K) outputs
• 1.8 V +100/–100 mV core power supply
• 1.5 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 36Mb and144Mb devices
• 165-bump, 15 mm x 17 mm, 1 mm bump pitch BGA package
• RoHS-compliant 165-bump BGA package available
SigmaQuad™ ECCRAM Overview
The GS8672D20/38BE are built in compliance with the
SigmaQuad-II+ ECCRAM pinout standard for Separate I/O
synchronous ECCRAMs. They are 75,497,472-bit (72Mb)
ECCRAMs. The GS8672D20/38BE SigmaQuad ECCRAMs
are just one element in a family of low power, low voltage
HSTL I/O ECCRAMs designed to operate at the speeds needed
to implement economical high performance networking
systems.
Clocking and Addressing Schemes
The GS8672D20/38BE SigmaQuad-II+ ECCRAMs 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.
Each internal read and write operation in a SigmaQuad-II+ B4
ECCRAM 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 ECCRAM is always two address
pins less than the advertised index depth (e.g., the 4M x18 has
a 1M addressable index).
On-Chip Error Correction Code
GSI's ECCRAMs implement an ECC algorithm that detects
and corrects all single-bit memory errors, including those
induced by Soft Error Rate (SER) events such as cosmic rays,
alpha particles. The resulting SER of these devices is
anticipated to be <0.002 FITs/Mb — a 5-order-of-magnitude
improvement over comparable SRAMs with no On-Chip ECC,
which typically have an SER of 200 FITs/Mb or more. SER
quoted above is based on reading taken at sea level.
However, the On-Chip Error Correction (ECC) will be
disabled if a “Half Write” operation is initiated. See the Byte
Write Contol section for further information.
tKHKH
tKHQV
-633
1.57 ns
0.45 ns
Parameter Synopsis
-550
1.81 ns
0.45 ns
-500
2.0 ns
0.45 ns
-450
2.2 ns
0.45 ns
-400
2.5 ns
0.45 ns
Rev: 1.03c 8/2017
1/30
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2011, GSI Technology