GS8162Z18BB-V Datasheet, PDF (13/33 Pages) GSI Technology – 18Mb Pipelined and Flow Through Synchronous NBT SRAM

Burst Counter Sequences
Linear Burst Sequence
A[1:0] A[1:0] A[1:0] A[1:0]
1st address
00
01
10
11
2nd address
01
10
11
00
3rd address
10
11
00
01
4th address
11
00
01
10
Note:
The burst counter wraps to initial state on the 5th clock.
Preliminary
GS8162ZxxB(B/D)-xxxV
Interleaved Burst Sequence
A[1:0] A[1:0] A[1:0] A[1:0]
1st address
00
01
10
11
2nd address
01
00
11
10
3rd address
10
11
00
01
4th address
11
10
01
00
Note:
The burst counter wraps to initial state on the 5th clock.
BPR 1999.05.18
Sleep Mode
During normal operation, ZZ must be pulled low, either by the user or by its internal pull down resistor. When ZZ is pulled high,
the SRAM will enter a Power Sleep mode after 2 cycles. At this time, internal state of the SRAM is preserved. When ZZ returns to
low, the SRAM operates normally after ZZ recovery time.
Sleep mode is a low current, power-down mode in which the device is deselected and current is reduced to I_SB2. The duration of
Sleep mode is dictated by the length of time the ZZ is in a High state. After entering Sleep mode, all inputs except ZZ become
disabled and all outputs go to High-Z The ZZ pin is an asynchronous, active high input that causes the device to enter Sleep mode.
When the ZZ pin is driven high, I_SB2 is guaranteed after the time tZZI is met. Because ZZ is an asynchronous input, pending
operations or operations in progress may not be properly completed if ZZ is asserted. Therefore, Sleep mode must not be initiated
until valid pending operations are completed. Similarly, when exiting Sleep mode during tZZR, only a Deselect or Read commands
may be applied while the SRAM is recovering from Sleep mode.
Sleep Mode Timing Diagram
tKH
tKC
tKL
CK
tZZS
tZZH
tZZR
ZZ
Designing for Compatibility
The GSI NBT SRAMs offer users a configurable selection between Flow Through mode and Pipeline mode via the FT signal
found on Bump 5R. Not all vendors offer this option, however most mark Bump 5R as V_DD or V_DDQ on pipelined parts and V_SS
on flow through parts. GSI NBT SRAMs are fully compatible with these sockets.
Rev: 1.01a 6/2006
13/33
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2004, GSI Technology