The MAX5959/MAX5960 quad hot-plug controllers are designed for PCI Express (PCIe) applications. These devices provide hot-plug control for the main 12V, 3.3V, and 3.3V auxiliary supplies of four PCIe slots. The MAX5959/MAX5960's logic inputs/outputs allow interfacing directly with the system hot-plug management controller or through an SMBusTM with an external I/O expander such as the MAX7313. An integrated debounced attention switch and present-detect signals simplify system design.