
W78958B
- 18 -
DC Characteristics, continued
PARAMETER
SYM.
TEST CONDITIONS
SPEC.
UNIT
MIN.
2.4
TYP.
-
MAX.
-
O/P High Voltage
V
OH2
I
OH2
= -400
μ
A
Note 3
(ALE,
PSEN
, P0, DP4, EMU)
I
OL2
= 2 mA
(AP5, AP6, AP7,
ESEL
, CLKS1)
I
OH2
= -100
μ
A
(AP5, AP6, AP7,
ESEL
, CLKS1)
V
DD
= 5V
±
10%
V
DD
= 5V
±
10%
V
DD
= 5V
±
10%, XTAL1
Note 5
V
DD
= 5V
±
10%, XTAL1
Note 5
V
DD
= 5V
±
10%, RESET
Note 5
V
DD
= 5V
±
10%, RESET
Note 5
V
O/P Low Voltage
V
OL3
-
-
0.45
V
O/P High Voltage
V
OH3
2.4
-
-
V
Input Voltage
Input Voltage
Input Voltage
Input Voltage
Input Voltage
Input Voltage
V
ILT
V
IHT
V
ILC
V
IHC
V
ILR
V
IHR
0
-
-
-
-
-
-
0.8
V
V
V
V
V
V
2.4
0
3.5
0
2.4
Note 4
0.8
Note 4
0.8
Note 4
Notes:
1. 0 < V
IN
< V
DD
, for ENSTD, INT 2 , INT 3 , RESET, EA , ICESET, Port 0, DP4, P1, P2, P3, and P8 inputs in leakage.
2. Using an internal pull low/high resistor (approx. 30K).
3. ALE, PSEN , P0 and DP4 in external program or data access mode.
4. The maximum input voltage is V
DD
+0.2V.
5. XTAL1 is a CMOS input and RESET is a Schmitt trigger input.
AC CHARACTERISTICS
AC specifications are a function of the particular process used to manufacture the product, 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
CP
), and actual parts will usually
experience less than a
±
20 nS variation. The figures below represent the performance expected from
a 0.8 micron CMOS process.
Refer to the W78C52 data sheet for further AC specifications.
Clock Input Waveform
PARAMETR
SYMBOL
F
OP
T
CP
T
CH
T
CL
MIN.
0
25
10
10
TYP.
-
-
-
-
MAX.
40
-
-
-
UNITS
MHz
nS
nS
nS
NOTES
1
2
3
3
Operating Speed
Clock Period
Clock High
Clock Low
Notes:
1. The clock may be stopped indefinitely in either state.
2. The T
CP
specification is used as a reference in other specifications.
3. There are no duty cycle requirements on the XTAL1 input.