Heres the Chipworks info on the chip [https://chipworks.secure.force.com/catalog/ProductDetails?sku=BRO-BCM5976A0KUB2G|bcm5976]. Here's ABI research info on the chip [http://www.abiresearch.com/research/product/1014876-brcm-bcm5976-touch-controller/|bcm5976]. Both need payment for there research if that is what you want.
As to getting the part there are many who offer it online.
The problem most people face here is they need to swap out the chip. But do to the tightness of the components on the iPad logic board you really can't replace the chip without killing the logic board.
Bottom line here: its just not economical to replace discreet components like this one on the iPad or iPad mini. Just get a new logic board in the long run it's cheaper.