MA818
TRIANGLE WAVE AT
CARRIER FREQUENCY,
SAMPLING ON
1VE
AND
2VE
PEAKS
PWM SWITCHING
INSTANTS
11
0
POWER WAVEFORM
AS READ FROM
EXTERNAL
PROM/EPROM
21
11
RESULTING
PWM
WAVEFORM
0
21
Fig. 3 Asynchronous PWM generation with‘double-edged’ regular sampling as used by the MA818
t
1
ALE
AS
t
1
t
2
RD
t
4
t
3
t
5
t
7
t
2
WR
t
3
t
4
DS
t
6
t
8
t
9
R/W
CS
t
8
t
10
t
11
CS
t
9
AD
0
-AD
7
t
10
t
11
t
15
LATCH ADDRESS
t
12
LATCH DATA
AD
0
-AD
7
t
15
LATCH ADDRESS
t
12
LATCH DATA
Fig. 4 Intel bus timing definitions
Parameter
ALE high period
Delay time, ALE to WR
WR low period
Delay time, WR high to ALE high
CS setup time
CS hold time
Address setup time
Address hold time
Data setup time
Data hold time
Symbol
t
1
t
2
t
3
t
4
t
8
t
9
t
10
t
15
t
11
t
12
Min.
70
40
200
40
20
0
30
30
100
30
Units
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
Fig. 5 Motorola bus timing definitions
Parameter
AS high period
Delay time, as low to DS high
DS high period
Delay time, DS low to AS high
DS low period
DS high to R/W low setup time
R/W hold time
CS setup time
CS hold time
Address setup time
Address hold time
Write data setup time
Write data hold time
Symbol
t
1
t
2
t
3
t
4
t
5
t
6
t
7
t
8
t
9
t
10
t
15
t
11
t
12
Min.
90
40
210
40
200
10
10
20
0
30
30
110
30
Units
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
Table 1 Intel bus timings at V
DD
= 5V, T
AMB
=
1
25°C
Table 2 Motorola bus timings at V
DD
= 5V, T
AMB
=
1
25°C
4