hi,
“No negative current injection allowed on PB0 pin.” means we can block the IC pins?
Thanks,
Can you give more detail , information as what part you are looking at ?
The datasheet is not very clear about the intended meaning of that note, but it likely refers to driving current through the pin using voltages that are outside the range of what is supplied to the part.
I’m not sure what is meant by “block the IC pins” but if by that you mean leaving it unconnected or using a resistance to pull it to either supply voltage, any of these should be acceptable.
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Thank you, zeinab.gerami1.
Today I learned something new.
The answer may be found in this application note:
Here is an excerpt:
4.6 EFFECT OF INJECTION CURRENT
ST microcontrollers have robust tolerance of additional leakage current introduced on analog
input signals as an effect of negative injection current. Negative injection current on any analog pin (or closely placed digital input pin) may introduce leakage current into the ADC input.
The worst case is the adjacent analog channel. Negative injection current is introduced when
VIN<VSS. Therefore current flows out from the I/O pin.
Analog pins can be protected against negative injection by adding a Schottky diode (pin to
ground).
The application note goes on to present an example and this helpful picture:
Best Wishes,
APDahlen
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