Initial situation:
Q1
is HIGH,Q3
is HIGH,Q5
is LOWD1
is forward biased,D2
is forward biased,D3
is reverse biased- Therefore,
Q3
is protected against shorting byD2
Next step:
Q1
is changed to LOW,Q3
remains HIGH,Q5
remains LOW- Nothing changed with
Q3
andQ5
, so, of courseD2
is still forward biased andD3
is still reverse biased Q1
did change, however, since only a very short period of time has passed,D1
didn't switch yet and is still forward biased as well- Therefore, for a very short period of time, current can flow from
Q3
HIGH, through forward biasedD1
intoQ1
LOW.
Is this true? Is this a problem? If not, why not?
I thought about setting every output pin to LOW for the necessary switching time according to the diodes' data sheet.