Pin 1= 0v Pin 2= 0v Pin 3= 0.749V Pin 4= 4.892v Pin 5= 0v Pin 6= 3.417v I’d say it would be an MMIC amp similar to this device. It has the same pin-out so it is a possibility. The Amp In my newer version is an 23 db gain device but 8-pin so I Suspect your version may have similar specs. Here is a Datasheet on the MGA-87563 6-pin device. http://www.efo.ru/components/avago/catalog/files/pdf/AV01_0200EN.PDF