HDMP-0421 Datasheet | Hewlett-Packard

Features - Supports ANSI X3T11 1.0625 Gbps FC-AL Loop Configuration - Supports 802.3z 1.25 Gbps Gigabit Ethernet (GE) Rates - Single PBC, CDR, Dual Signal Detect (SD) in a Single Package - Bidirectional, Symmetric Bypass Capability - CDR in Bypass Path and Loop Path - CDR Location Determined by Wiring Configuration of Pins on PCB (Patent Pending) - Envelope Detect on Cable Input (SD) for Both Directions - Equalizers On All Inputs - High Speed PECL I/Os Referenced to VCC - Buffered Line Logic (BLL) Outputs without External Bias Resistors - 0.4 W Typical Power at VCC = 3.3 V - 5 V Tolerant LVTTL I/O - 24 Pin SSOP Package HDMP-0421 Single PBC & CDR Description The HDMP-0421 is a Single Port Bypass Circuit (PBC) with Clock and Data Recovery (CDR), and dual Signal Detect (SD) capability. This configuration will control jitter accumulation while repeating ining signals. Port Bypass Circuits are used to provide loops that are continuously on in hard disk arrays constructed in Fibre Channel Arbitrated Loop (FC-AL) configurations. Hard disks may be pulled out or swapped while other disks in the array are available to the system. This device may also be used in multi-initiator loop configurations. A Port Bypass Circuit is a 2:1 Multiplexer array with two modes of operation: DISK IN LOOP and DISK BYPASSED. In DISK IN LOOP mode, the loop goes into and out of the disk drive. Data go from the HDMP-0421’s TO_NODE[n]± differential output pins to the Disk Drive Transceiver IC (for example, an HDMP-1536A) Rx± differential input pins. Data from the Disk Drive Transceiver IC Tx± differential output pins go to the HDMP-0421’s FM_NODE[n]± differential input pins. Figures 4 and 5 show connection diagrams for disk drive array applications. In DISK BYPASSED mode, the disk drive is either absent or non-functional and the loop bypasses the hard disk. DISK IN LOOP mode is enabled with a HIGH on the BYPASS[n]- pin and DISK BYPASSED mode is enabled with a LOW on the same pin. Multiple...