
6
8Mb: 512K x 18, 256K x 32/36 Pipelined ZBT SRAM
Micron Technology, Inc., reserves the right to change products or specifications without notice.
MT55L512L18P_C.p65 – Rev. 2/02
2002, Micron Technology, Inc.
8Mb: 512K x 18, 256K x 32/36
PIPELINED ZBT SRAM
TQFP PIN DESCRIPTIONS
x18
x32/x36
SYMBOL TYPE
DESCRIPTION
37
SA0
Input
Synchronous Address Inputs: These inputs are registered
36
SA1
and must meet the setup and hold times around the rising
32-35, 44-50,
SA
edge of CLK. Pin 84 is reserved as an address bit for
80-83, 99, 100
81-83, 99, 100
higher-density 18Mb ZBT SRAMs. SA0 and SA1 are the
two least significant bits (LSB) of the address field and
set the internal burst counter if burst is desired.
93
BWa#
Input
Synchronous Byte Write Enables: These active LOW inputs
94
BWb#
allow individual bytes to be written when a WRITE cycle is
–
95
BWc#
active and must meet the setup and hold times around the
–
96
BWd#
rising edge of CLK. BYTE WRITEs need to be asserted on
the same cycle as the address. BWs are associated with
addresses and apply to subsequent data. BWa# controls
DQa pins; BWb# controls DQb pins; BWc# controls DQc
pins; BWd# controls DQd pins.
89
CLK
Input
Clock: This signal registers the address, data, chip enables,
byte write enables, and burst control inputs on its rising
edge. All synchronous inputs must meet setup and hold
times around the clock’s rising edge.
98
CE#
Input
Synchronous Chip Enable: This active LOW input is used to
enable the device and is sampled only when a new
external address is loaded (ADV/LD# is LOW).
92
CE2#
Input
Synchronous Chip Enable: This active LOW input is used to
enable the device and is sampled only when a new
external address is loaded (ADV/LD# is LOW). This
input can be used for memory depth expansion.
97
CE2
Input
Synchronous Chip Enable: This active HIGH input is used to
enable the device and is sampled only when a new
external address is loaded (ADV/LD# is LOW). This
input can be used for memory depth expansion.
86
OE#
Input
Output Enable: This active LOW, asynchronous input
(G#)
enables the data I/O output drivers. G# is the JEDEC-
standard term for OE#.
85
ADV/LD# Input
Synchronous Address Advance/Load: When HIGH, this
input is used to advance the internal burst counter,
controlling burst access after the external address is
loaded. When ADV/LD# is HIGH, R/W# is ignored. A LOW
on ADV/LD# clocks a new address at the CLK rising edge.
87
CKE#
Input
Synchronous Clock Enable: This active LOW input permits
CLK to propagate throughout the device. When CKE# is
HIGH, the device ignores the CLK input and effectively
internally extends the previous CLK cycle. This input must
meet setup and hold times around the rising edge of CLK.
64
ZZ
Input
Snooze Enable: This active HIGH, asynchronous input
causes the device to enter a low-power standby mode in
which all data in the memory array is retained. When ZZ is
active, all other inputs are ignored.
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