Hi,
I am using the BQ51050B in my design and I have problems figuring out the correct capacitor values to use with my coil.
First I tried 760 308 101 303 with the values seen in the schematic. Next I tried the 760308102207 with C1=150nF, C2=1.9nF and also C1=340nF, C2 3.5nF (capacitors have 10% tolerances). Nothing seemed to work.
I measured the signals with oscilloscope and input voltage seems ok (signal is similar to what the charger sends), but the voltage on RECT pin is only about 100mV. I have attached pictures from my measurements. Measurements were taken with 760308102207 coil and C1=340nF, C2=3.5nF. Load is a single cell lipo battery with 1200mAh.
R29 in schematic is not populated so the CHG pin is currently floating.
Ideally I would like to use the first (smaller) coil but I am aware of potential problems due to size so the second one is also an option.