HYUNDAI MicroElectronics
GMS90 Series
AC Characteristics for GMS90 series (16MHz version)
VCC= 3.3V + 0.3V, −0.6V; VSS= 0V; TA= 0°C to 70°C
(CL for port 0. ALE and PSEN outputs = 50pF; CL for all other outputs = 50pF)
External Program Memory Characteristics
16 MHz Oscillator
Variable Oscillator
1/tCLCL = 3.5 to 16MHz
Parameter
Symbol
Unit
Min.
85
23
23
-
Max.
Min.
Max.
tLHLL
-
2tCLCL-40
-
ALE pulse width
ns
ns
ns
ns
ns
ns
ns
ns
tAVLL
tLLAX
tLLIV
-
-
tCLCL-40
-
Address setup to ALE
tCLCL-40
-
Address hold after ALE
ALE low to valid instruction in
ALE to PSEN
150
-
-
4tCLCL-100
tLLPL
tPLPH
tPLIV
tPXIX
38
153
-
tCLCL-25
-
-
3tCLCL-35
-
PSEN pulse width
88
-
-
0
-
3tCLCL-100
-
PSEN to valid instruction in
Input instruction hold after PSEN
Input instruction float after PSEN
0
†
-
43
tCLCL-20
ns
ns
tPXIZ
†
55
-
tCLCL-8
-
Address valid after PSEN
Address to valid instruction in
Address float to PSEN
tPXAV
tAVIV
tAZPL
-
198
-
-
5tCLCL-115
-
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.
34
Oct. 2000 Ver 3.1a