I want to use this part https://www.mouser.ca/ProductDetail/TE-Connectivity/1776244-2?qs=vnwGVgFuQiYN9Kdzo4mAWw%3D%3D on my PCB. However the schematic and PCB footprint mouser provides is unclear to me. Why are there 4 pins and what is my signal and ground pin? The data sheet does not provide any detail either.