stk16ca8 Simtek Corporation, stk16ca8 Datasheet - Page 9

• Manufacturer Part Number: stk16ca8
• Description: 128k Autostoreplus?? Nvsram Quantumtrap?? Cmos Nonvolatile Static
• Manufacturer: Simtek Corporation

valid. After the t
the
WRITE
SOFTWARE NONVOLATILE RECALL
A software
of
ware
the following sequence of
tions must be performed:
Internally,
SRAM
information is transferred into the
the t
ready for
operation in no way alters the data in the nonvolatile
elements. The nonvolatile data can be recalled an
unlimited number of times.
HARDWARE PROTECT
The STK16CA8 offers hardware protection against
inadvertent
ing low-voltage conditions. When V
externally initiated
WRITE
PREVENTING STORES
The AutoStore™ function can be disabled on the fly
by initiating an AutoStore Inhibit sequence. A
sequence of read operations is performed in a man-
ner similar to the software STORE initiation. To ini-
tiate the AutoStore Inihibit sequence, the following
sequence of E controlled read operations must be
performed:
Once the AutoStore™ inhibit has been initiated, it
will remain active until an AutoStore™ inhibit off
September 2003
1. Read address
2. Read address
3. Read address
4. Read address
5. Read address
6. Read address
1. Read address
2. Read address
3. Read address
4. Read address
5. Read address
6. Read address
READ
SRAM
RECALL
STORE
s will be inhibited.
data is cleared, and second, the nonvolatile
operation.
operations in a manner similar to the soft-
READ
RECALL
cycle time the
RECALL
will again be activated for
STORE
initiation. To initiate the
and
STORE
is a two-step procedure. First, the
operation and
cycle is initiated with a sequence
4E38 (hex)
B1C7 (hex)
83E0 (hex)
7C1F (hex)
703F (hex)
4C63 (hex)
4E38 (hex)
B1C7 (hex)
83E0 (hex)
7C1F (hex)
703F (hex)
8B45 (hex)
STORE
WRITE
cycle time has been fulfilled,
SRAM
E
operations. The
controlled
operations and
will once again be
SRAM WRITE
Valid READ
Valid READ
Valid READ
Valid READ
Valid READ
Initiate RECALL cycle
Valid READ
Valid READ
Valid READ
Valid READ
Valid READ
AutoStore Inhibit
SRAM
CCX
RECALL
READ
< V
READ
cells. After
SWITCH
RECALL
opera-
cycle,
SRAM
s dur-
and
, all
9
sequence has been performed, regardless of device
power cycles.
The AutoStore Inhibit can be disabled by initiating
an AutoStore Inhibit Off sequence. A sequence of
read operations is performed in a manner similar to
the software RECALL initiation. To initiate the
AutoStore Inhibit Off sequence, the following
sequence of E controlled read operations must be
performed:
LOW AVERAGE ACTIVE POWER
The STK16CA8 draws significantly less current
when it is cycled at times longer than 50ns. Figure 3
shows the relationship between I
time. Worst-case current consumption is shown for
both
perature range, V
enable). Figure 4 shows the same relationship for
WRITE
than 100%, only standby current is drawn when the
chip is disabled. The overall average current drawn
by the STK16CA8 depends on the following items:
1)
chip enable; 3) the overall cycle rate for accesses;
4) the ratio of
temperature; 6) the V
1. Read address
2. Read address
3. Read address
4. Read address
5. Read address
6. Read address
CMOS
Document Control # ML0023 rev 0.1
CMOS
cycles. If the chip enable duty cycle is less
vs.
and
TTL
READ
TTL
CC
input levels; 2) the duty cycle of
= 3.6V, 100% duty cycle on chip
4E38 (hex)
B1C7 (hex)
83E0 (hex)
7C1F (hex)
703F (hex)
4B46 (hex)
s to
cc
input levels (commercial tem-
level; and 7) I/O loading.
WRITE
s; 5) the operating
CC
Valid READ
Valid READ
Valid READ
Valid READ
Valid READ
AutoStore Inhibit Off
and
STK16CA8
READ
cycle