Hi All, Happy Christmas
I have another post where I am discussing charging a Li-Poly with a solar panel. I did not want to post this question on the same topic to avoid any confusion. This issue was noticed while experimenting while charging with both benchtop power supplies as well.
My boards all use a simple ST4054 charger ic. The charge current is set to a max 0.66A, and Input Voltage is set to 5.5V.
If I were to limit the current on the power supply to 0.25A or less, I noticed a high pitch noise from the charger IC.
When the ST4054 charger has less current than required, the VIN drops to a little above the battery voltage but continues charging the battery.
This noise will not really have to affect anyone's ears as it is kept in an enclosure and placed outside, but can this have any damage to the IC?