HDMP-0422 Datasheet | Hewlett-Packard

Features - Supports 1.0625 GBd Fibre Channel operation - Supports 1.25 GBd Gigabit Ethernet (GE) operation - Single PBC/CDR in one package - CDR location determined by choice of cable input/output - Amplitude valid and data valid detection (Fibre channel rate only) on FM_NODE[0] input - Equalizers on all inputs - High-speed LVPECL I/O - Buffered Line Logic (BLL) outputs (no external bias resistors required) - 0.46 W typical power at VCC = 3.3 V - 24 Pin, low-cost SSOP package Applications - RAID, JBOD, BTS cabinets - One 2:1 muxes - One 1:2 buffers - 1 ≥ N Gigabit serial buffer - N ≥ 1 Gigabit serial mux Description The HDMP-0422 is a Single Port Bypass Circuit (PBC) with Clock and Data Recovery (CDR) capability included. This integrated circuit provides a low-cost, lowpower physical-layer solution for Fibre Channel Arbitrated Loop (FC-AL) disk array configurations. By using a PBC such as the HDMP0422, hard disks may be pulled out or swapped while other disks in the array are available to the system. A PBC consists of multiple 2:1 multiplexers daisy chained along with a CDR. Each port has two modes of operation: “disk in loop” and “disk bypassed.” When the “disk in loop” mode is selected, the loop goes into and out of the disk drive at that port. For example, data goes from the HDMP-0422’s TO_NODE[n]± differential output pins to the Disk Drive Transceiver IC’s (e.g. an HDMP-1636A) Rx differential input pins. Data from the Disk Drive Transceiver IC’s Tx differential outputs goes to the HDMP-0422’s FM_NODE[n]± differential input pins. Figures 2 and 3 show connection diagrams for disk drive array applications. When the “disk bypassed” mode is selected, the disk drive is either absent or non-functional and the loop bypasses the hard disk. The “disk bypassed” mode is enabled by pulling the BYPASS[n]pin low. Leave BYPASS[n]floating to enable the “disk in loop” mode. HDMP-0422s may be cascaded with other members of the HDMP-04XX/HDMP-05XX family through the appropriate...