All IC you used do the same thing; protect the USB port from overcurrents. There is nothing special with G545A1. All that differ from them is the enable pin active on high or low, overcurrent protection setting and current limit. according to
this it's equiv are:AP2191AMPG, TPS2069DGN, RT9711APF/RT9715CGF. This IC should be found in: HP Mini 700, LENOVO G410(LA-3691), G550(LA-5082), N200(LA-3451), G450(5081), N500, Y430, F41... Just for test connect pins 2,3 to output 6,7 and 8 and check if it's working without IC...