Hi,
My attached schematic is to LM25011 to charge supercapacitors.
Input voltage: 9 - 36V
Nominal voltage: 12V
Charging Current: ~1A
Vout: 9.4V
With nominal input 12V, the circuit had to charge up the supercapacitor.
However, with input 9 - 10V, the supercapacitors would still be charged at the early stage. However, I found the VOUT would oscillate when the supercapacitors were fully charged and loading current was low.
The min. off time was shorter than 90ns at that time. As I understand, the boostrap capacitor may not have enough time to be charged up. This may somehow cause the oscillation.
Is is possible to avoid the oscillation? I can accept the lower Vout when Vin is low.
I tried to add some loading current at VOUT so that the the oscillation could be fixed. But the loading current had to be > 100mA, it is too much...
Regards,
Alex Poon
