HYUNDAI MicroElectronics
GMS90 Series
AC Characteristics for GMS90 series (24MHz version)
VCC= 5V + 10%, −15%; VSS= 0V; TA= 0°C to 70°C
(CL for port 0. ALE and PSEN outputs = 100pF; CL for all other outputs = 80pF)
External Program Memory Characteristics
24 MHz Oscillator
Variable Oscillator
1/tCLCL = 3.5 to 24MHz
Parameter
Symbol
Unit
Min.
43
17
17
-
Max.
Min.
Max.
tLHLL
-
-
2tCLCL-40
-
ALE pulse width
ns
ns
ns
ns
ns
ns
ns
ns
tAVLL
tLLAX
tLLIV
tCLCL-25
-
Address setup to ALE
-
tCLCL-25
-
Address hold after ALE
ALE low to valid instruction in
ALE to PSEN
80
-
-
4tCLCL-87
tLLPL
tPLPH
tPLIV
tPXIX
22
95
-
tCLCL-20
-
-
3tCLCL-30
-
PSEN pulse width
60
-
-
0
-
3tCLCL-65
-
PSEN to valid instruction in
Input instruction hold after PSEN
Input instruction float after PSEN
0
†
-
32
tCLCL-10
ns
ns
tPXIZ
†
37
-
tCLCL-5
-
Address valid after PSEN
Address to valid instruction in
Address float to PSEN
tPXAV
tAVIV
tAZPL
-
148
-
-
5tCLCL-60
-
ns
ns
0
0
†
Interfacing the GMS90 series to devices with float times up to 35 ns is permissible. This limited bus contention will not cause
any damage to port 0 Drivers.
36
Oct. 2000 Ver 3.1a