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ST72521B
154/198
11.2 ABSOLUTE MAXIMUM RATINGS
Stresses above those listed as “absolute maxi-
mum ratings” may cause permanent damage to
the device. This is a stress rating only and func-
tional operation of the device under these condi-
11.2.1 Voltage Characteristics
tions is not implied. Exposure to maximum rating
conditions for extended periods may affect device
reliability.
11.2.2 Current Characteristics
Notes:
1. Directly connecting the RESET and I/O pins to V
or V
could damage the device if an unintentional internal reset
is generated or an unexpected change of the I/O configuration occurs (for example, due to a corrupted program counter).
To guarantee safe operation, this connection has to be done through a pull-up or pull-down resistor (typical: 4.7k
for
RESET, 10k
for I/Os). For the same reason, unused I/O pins must not be directly tied to V
DD
or V
SS
.
2. I
must never be exceeded. This is implicitly insured if V
IN
maximum is respected. If V
maximum cannot be
respected, the injection current must be limited externally to the I
value. A positive injection is induced by V
>V
while a negative injection is induced by V
<V
. For true open-drain pads, there is no positive injection current, and the
corresponding V
IN
maximum must always be respected
3. All power (V
DD
) and ground (V
SS
) lines must always be connected to the external supply.
4. Negative injection disturbs the analog performance of the device. See note in
“ADC Accuracy” on page 184
.
For best reliability, it is recommended to avoid negative injection of more than 1.6mA.
5. When several inputs are submitted to a current injection, the maximum
Σ
I
is the absolute sum of the positive
and negative injected currents (instantaneous values). These results are based on characterisation with
Σ
I
INJ(PIN)
maxi-
mum current injection on four I/O port pins of the device.
6. True open drain I/O port pins do not accept positive injection.
Symbol
Ratings
Maximum value
Unit
V
DD
- V
SS
Supply voltage
Input Voltage on true open drain pin
Input voltage on any other pin
Variations between different digital power pins
Variations between digital and analog ground pins
Electro-static discharge voltage (Human Body Model)
Electro-static discharge voltage (Machine Model)
6.5
V
V
IN 1) & 2)
V
SS
-0.3 to 6.5
V
SS
-0.3 to V
DD
+0.3
50
50
|
V
DDx
| and |
V
SSx
|
|V
SSA
- V
SSx
|
V
ESD(HBM)
V
ESD(MM)
mV
see
Section 11.8.3 on page 168
Symbol
Ratings
Maximum value
Unit
I
VDD
I
VSS
Total current into V
DD
power lines (source)
3)
Total current out of V
SS
ground lines (sink)
3)
Output current sunk by any standard I/O and control pin
Output current sunk by any high sink I/O pin
Output current source by any I/Os and control pin
Injected current on RESET pin
Injected current on OSC1 and OSC2 pins
Injected current on any other pin
5) & 6)
Total injected current (sum of all I/O and control pins)
5)
150
150
25
50
- 25
± 2
± 5
± 5
± 25
mA
I
IO
mA
I
INJ(PIN) 2) & 4)
Σ
I
INJ(PIN) 2)