Hi Team
What is the problem with the following conditions?
Input 24V, output 12V/3A
Input voltage drops slowly to 9V
Whether the output voltage can be maintained above 8.6V
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Hi Team
What is the problem with the following conditions?
Input 24V, output 12V/3A
Input voltage drops slowly to 9V
Whether the output voltage can be maintained above 8.6V
Hi Allen,
I have calculated and think that it can be maintained above 8.6V. As you can see that Fsw will drop to 140kHz in dropout mode.
SoToff=(1-D)⋅T=(1-8.6V/9V)⋅(1/f)=317ns, and it is higher than T-off_min =70ns. We can get that it can be guaranteed.
Thanks
Colin
But FB Pin is set to 12V out
Will the input voltage drop to 9V have any Issue?
Hi Allen,
It is ok when Vin < Vout, this condition we call dropout mode and output voltage will fall with the input voltage until device shut down.
Thanks
Colin