The dropout for all IC regulators is spec'd when the output has dropped -100mV.
The output has dropped because the input voltage is too low for the regulator to regulate the output voltage.
The output has droppes 100mV from 3.3V?
So when i'll insert 4.5V i'll get 3.2V?
If so, then why didnt they just say that for 800mA, there is a 1.3V instead of saying 1.2V dropout?
The output has droppes 100mV from 3.3V?
So when i'll insert 4.5V i'll get 3.2V?
If so, then why didnt they just say that for 800mA, there is a 1.3V instead of saying 1.2V dropout?
For an output current of 800mA, the IC drops out (with its output voltage 100mV too low) when its input voltage is only 3.3V + 1.2V= 4.5V.
The input voltage must be higher than 4.5V for good regulation.
The datasheet spec's warn you that if the current is 800mA and the input voltage is only 4.5V then some of the regulators have an output that is not regulated and the output voltage will drop to 3.2V.