The typical usage model is to locate the ECE1119/ECE1117 in the keyboard assembly. By mounting the ECE1119/ECE1117 onto the keyboard assembly, the keyboard and touchpad/point stick PS/2 signals and the backlight PWMs are routed from the keyboard to the motherboard over a single BC-Link connection. In all other notebook designs without BC companion device, the signals from the keyboard matrix, PS/2 and LED are routed to the motherboard via a wide ribbon extension for the keyboard switch circuit. ECE1119 communicates to the upstream host via BC-Link or SMBus and provides up to three downstream BC-LinkTM or SMBus ports to permit communication between the upstream host and downstream companion devices. Family parts ECE1117-HZH ECE1117-HZH-1 ECE1117-HZH-1-TR ECE1117-HZH-TR ECE1117-Y3-1-TR