SAF-C502-2R20N Siemens Semiconductor Group, SAF-C502-2R20N Datasheet - Page 35

• Manufacturer Part Number: SAF-C502-2R20N
• Description: 8-Bit CMOS Microcontroller
• Manufacturer: Siemens Semiconductor Group

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Semiconductor Group
Capacitive loading on ports 0 and 2 may cause spurious noise pulses to be superimposed on the
and port 3. The noise is due to external bus capacitance discharging into the port 0 and port 2 pins when these
pins make 1-to-0 transitions during bus operation. In the worst case (capacitive loading > 100 pF), the noise
pulse on ALE line may exceed 0.8 V. In such cases it may be desirable to qualify ALE with a schmitt-trigger,
or use an address latch with a schmitt-trigger strobe input.
Capacitive loading on ports 0 and 2 may cause the
0.9
I
EA = Port0 =
I
XTAL1 driven with
EA = Port0 = RESET =
is used (appr. 1 mA).
I
XTAL1 driven with
RESET = EA =
I
active mode:
idle mode:
where
PD
CC
CC
CC max
(Power Down Mode) is measured under following conditions:
(active mode) is measured with:
(Idle mode) is measured with all output pins disconnected and with all peripherals disabled;
V
CC
at other frequencies is given by:
f
OSC
specification when the address lines are stabilizing.
is the oscillator frequency in MHz.
V
CC
V
I
I
CC max
CC max
SS
; RESET =
t
t
; Port0 =
CLCH
CLCH
= 1.32 x
= 0.40 x
,
,
V
t
t
CHCL
CC
CHCL
; all other pins are disconnected.
V
V
CC
= 5 ns,
= 5 ns,
SS
; all other pins are disconnected;
f
f
; XTAL2 = N.C.; XTAL1 =
OSC
OSC
+ 7.48
+ 2.62
V
V
IL
IL
=
=
V
V
SS
SS
I
CC
+ 0.5 V,
+ 0.5 V,
values are given in mA and measured at
34
V
V
V
OH
IH
IH
on ALE and PSEN to momentarily fall bellow the
V
=
=
SS
V
V
I
CC
; all other pins are disconnected.
CC
CC
would be slightly higher if a crystal oscillator
– 0.5 V; XTAL2 = N.C.;
– 0.5 V; XTAL2 = N.C.;
V
CC
= 5 V.
V
OL
C502
of ALE