CY7C1049B
Document #: 38-05169 Rev. *A Page 4 of 10
Switching Characteristics
[4]
Over the Operating Range
7C1049B-12 7C1049B-15 7C1049B-17
Parameter Description Min. Max. Min. Max. Min. Max. Unit
Read Cycle
t
power
V
CC
(typical) to the First Access
[5]
111ms
t
RC
Read Cycle Time 12 15 17 ns
t
AA
Address to Data Valid 12 15 17 ns
t
OHA
Data Hold from Address Change 3 3 3 ns
t
ACE
CE LOW to Data Valid 12 15 17 ns
t
DOE
OE LOW to Data Valid 6 7 8 ns
t
LZOE
OE LOW to Low Z
[7]
000ns
t
HZOE
OE HIGH to High Z
[6, 7]
677ns
t
LZCE
CE LOW to Low Z
[7]
333ns
t
HZCE
CE HIGH to High Z
[6, 7]
677ns
t
PU
CE LOW to Power-Up 0 0 0 ns
t
PD
CE HIGH to Power-Down 12 15 17 ns
Write Cycle
[8, 9]
t
WC
Write Cycle Time 12 15 17 ns
t
SCE
CE LOW to Write End 10 12 12 ns
t
AW
Address Set-Up to Write End 10 12 12 ns
t
HA
Address Hold from Write End 0 0 0 ns
t
SA
Address Set-Up to Write Start 0 0 0 ns
t
PWE
WE Pulse Width 10 12 12 ns
t
SD
Data Set-Up to Write End 7 8 8 ns
t
HD
Data Hold from Write End 0 0 0 ns
t
LZWE
WE HIGH to Low Z
[7]
333ns
t
HZWE
WE LOW to High Z
[6, 7]
678ns
Notes:
4. Test conditions assume signal transition time of 3 ns or less, timing reference levels of 1.5V, input pulse levels of 0 to 3.0V, and output loading of the specified
I
OL
/I
OH
and 30-pF load capacitance.
5. This part has a voltage regulator which steps down the voltage from 5V to 3.3V internally. t
power
time has to be provided initially before a read/write operation
is started.
6. t
HZOE
, t
HZCE
, and t
HZWE
are specified with a load capacitance of 5 pF as in part (b) of AC Test Loads. Transition is measured ±500 mV from steady-state voltage.
7. At any given temperature and voltage condition, t
HZCE
is less than t
LZCE
, t
HZOE
is less than t
LZOE
, and t
HZWE
is less than t
LZWE
for any given device.
8. The internal write time of the memory is defined by the overlap of CE
LOW, and WE LOW. CE and WE must be LOW to initiate a write, and the transition of either of
these signals can terminate the write. The input data set-up and hold timing should be referenced to the leading edge of the signal that terminates the write.
9. The minimum write cycle time for Write Cycle no. 3 (WE
controlled, OE LOW) is the sum of t
HZWE
and t
SD
.
