Specifications
ST72104Gx, ST72215Gx, ST72216Gx, ST72254Gx
118/141
13.8 I/O PORT PIN CHARACTERISTICS
13.8.1 General Characteristics
Subject to general operating conditions for V
DD
, f
OSC
, and T
A
unless otherwise specified.
Figure 78. Two typical Applications with unused I/O Pin
Figure 79. Typical I
PU
vs. V
DD
with V
IN
=V
SS
Notes:
1. Unless otherwise specified, typical data are based on T
A
=25°C and V
DD
=5V.
2. Data based on characterization results, not tested in production.
3. Hysteresis voltage between Schmitt trigger switching levels. Based on characterization results, not tested.
4. Configuration not recommended, all unused pins must be kept at a fixed voltage: using the output mode of the I/O for
example or an external pull-up or pull-down resistor (see
Figure 78). Data based on design simulation and/or technology
characteristics, not tested in production.
5. The R
PU
pull-up equivalent resistor is based on a resistive transistor (corresponding I
PU
current characteristics de-
scribed in Figure 79). This data is based on characterization results, tested in production at V
DD
max.
6. Data based on characterization results, not tested in production.
7. To generate an external interrupt, a minimum pulse width has to be applied on an I/O port pin configured as an external
interrupt source.
Symbol Parameter Conditions Min Typ
1)
Max Unit
V
IL
Input low level voltage
2)
0.3xV
DD
V
V
IH
Input high level voltage
2)
0.7xV
DD
V
hys
Schmitt trigger voltage hysteresis
3)
400 mV
I
L
Input leakage current V
SS
≤V
IN
≤V
DD
±1
µA
I
S
Static current consumption
4)
Floating input mode 200
R
PU
Weak pull-up equivalent resistor
5)
V
IN
=V
SS
V
DD
=5V 62 120 250
kΩ
V
DD
=3.4V 170 200 300
C
IO
I/O pin capacitance 5 pF
t
f(IO)out
Output high to low level fall time
6)
C
L
=50pF
Between 10% and 90%
25
ns
t
r(IO)out
Output low to high level rise time
6)
25
t
w(IT)in
External interrupt pulse time
7)
1 t
CPU
10kΩ
UNUSED I/O PORT
ST72XXX
10kΩ
UNUSED I/O PORT
ST72XXX
V
DD
3.2 3.5 4 4.5 5 5.5
Vdd [V]
0
10
20
30
40
50
60
70
Ipu [µA]
Ta=-40°C
Ta=25°C
Ta=85°C
Ta=125°C