I'm using the LT3741 for a constant current battery charging application. However, when I enable the converter, power seems to flow back into the input side (the input benchtop PSU turns off due to an over voltage fault). It seems that the bottom MOSFET turns on too long perhaps that the load current reverses through the inductor (because the load is a battery). And then when the bottom MOSFET turns off, I think it's acting like a boost converter in the reverse direction. Is this a known issue? Is there a way to avoid this other than by putting a diode on the output path before the battery?