GMS90C320
34
OCT. 2000 Ver 1.2
AC Characteristics for 50MHz version
V
C C
= 5V + 10%,
−
15%; V
S S
= 0V; T
A
= 0
°
C to 70
°
C
(C
L
for port 0. ALE and PSEN outputs = 100pF; C
L
for all other outputs = 80pF)
Variable Clock : V
C C
= 5V, 1/
t
C LC L
= 3.5MHz to 50 MHz
External Program Memory Characteristics
Parameter
Symbol
50 MHz Oscillator
Variable Oscillator
1/t
C LCL
= 3.5 to 50MHz
Unit
Min.
Max.
Min.
Max.
ALE pulse width
t
LH LL
25
-
2t
C LC L
−
15
-
ns
Address setup to ALE
t
A VLL
5
-
t
C LC L
−
15
-
ns
Address hold after ALE
t
LLA X
5
-
t
C LC L
−
15
-
ns
ALE low to valid instruction in
t
LLIV
-
40
-
4t
C LC L
−
40
ns
ALE to PSEN
t
LLP L
5
-
t
C LC L
−
15
-
ns
PSEN pulse width
t
P LP H
45
-
3t
C LC L
−
15
-
ns
PSEN to valid instruction in
t
P LIV
-
20
-
3t
C LC L
−
40
ns
Input instruction hold after PSEN
t
P XIX
0
-
0
-
ns
Input instruction float after PSEN
t
P XIZ
1)
1)
Interfacing the GMS90C320 to devices with float times up to 20 ns is permissible. This limited bus contention will not cause any damage
to port 0 Drivers.
-
10
-
t
C LC L
−
10
ns
Address valid after PSEN
t
P XA V
1)
15
-
t
C LC L
−
5
-
ns
Address to valid instruction in
t
A VIV
-
45
-
5t
C LC L
−
55
ns
Address float to PSEN
t
A ZP L
-5
-
-5
-
ns