W78E58B Winbond, W78E58B Datasheet - Page 20

• Manufacturer Part Number: W78E58B
• Description: 8 BIT MICROCONTROLLER
• Manufacturer: Winbond

10. AC CHARACTERISTICS
The AC specifications are a function of the particular process used to manufacture the part, the ratings
of the I/O buffers, the capacitive load, and the internal routing capacitance. Most of the specifications
can be expressed in terms of multiple input clock periods (T
experience less than a 20 nS variation. The numbers below represent the performance expected
from a 0.6 micron CMOS process when using 2 and 4 mA output buffers.
Clock Input Waveform
Notes:
1. The clock may be stopped indefinitely in either state.
2. The T
3. There are no duty cycle requirements on the XTAL1 input.
Program Fetch Cycle
Notes:
1. P0.0
2. Memory access time is 3 T
3. Data have been latched internally prior to PSEN going high.
4. " " (due to buffer driving delay and wire loading) is 20 nS.
Operating Speed
Clock Period
Clock High
Clock Low
Address Valid to ALE Low
Address Hold from ALE Low
ALE Low to
Data Hold after PSEN High
Data Float after PSEN High
ALE Pulse Width
PSEN
PSEN Pulse Width
CP
P0.7, P2.0
Low to Data Valid
specification is used as a reference in other specifications.
PARAMETER
PARAMETER
PSEN
P2.7 remain stable throughout entire memory cycle.
Low
XTAL1
CP
.
SYMBOL
SYMBOL
T
T
T
T
T
T
T
T
F
T
T
T
PSW
ALW
AAH
PDA
PDH
AAS
PDZ
APL
OP
CP
CH
CL
T
CH
- 20 -
1 T
1 T
1 T
2 T
3 T
MIN.
MIN.
F
25
10
10
OP,
0
CP
CP
CP
0
0
CP
CP
-
-
-
-
-
-
T
CP
T
2 T
3 T
CL
TYP.
TYP.
-
-
-
-
-
-
-
-
-
-
CP
CP
CP
), and actual parts will usually
2 T
1 T
1 T
MAX.
MAX.
40
-
-
-
-
-
-
-
-
CP
CP
CP
UNIT
UNIT
MHz
nS
nS
nS
nS
nS
nS
nS
nS
nS
nS
nS
W78E58B
NOTES
NOTES
1, 4
1
2
3
3
4
4
2
3
4
4