XDP™ 4+1 phase dual loop digital multiphase controller The XDP™ XDPE12254C is a digital dual rail 4+1 phase controller to power Intel VR13, VR13HC, IMVP8 and IMVP9 server, workstation & high-end desktop applications. It offers flexible phase assignment between the two loops and can be configured as: 4+1, 3+1, ... ,1+1. Digital technology implements all control functions for flexibility and stability. Advanced control loop features enable optimal response to high slew rate load transients.