Power over Ethernet (PoE) offers an easy and reliable solution to combine power and data in one cable with high data rate and long reach. This combination makes PoE ideal for small devices such as machine vision cameras and vision sensors. This reference design implements a complete PoE powered device (PD) including a 1-Gb/s physical layer and a highly efficient: isolated power solution in a very small form factor of 27 x 27 mm.