Help with battery charging circuit

hi,
im building this circuit just noticed a strange value resistor that supplys the + to the circuit 0.4 ohms just wondering what this r does? and if i really need it im guessing it may act as a filter of some sort
thanks

low ohm.png

It's probably a polyfuse or fusible resistor to protect your supply if the chip fails.

// Per.

didnt think of that yes your correct poly fuses are really low resistance thanks

Or its to limit inrush current at startup? Its marked as optional and not explained in the DS...

MarkT: Or its to limit inrush current at startup? Its marked as optional and not explained in the DS...

Well, the chip does limit inrush current itself, so i think it's just a fuse.

They probably just thought it would be a good idea adding it to the schematic in the datasheet to keep their ass out of trouble if one of their chips decides to do suicide and destroy something behind it.

// Per.