TI DS125BR800A SAS－3协议中继器解决方案

TI公司的S125BR800A是能驱动SAS-3协议的8路信号调理器,支持最新的SCSI标准的最快数据速率,高达12.5Gbps,并和目前的3Gbps和6Gbps SAS链接速率兼容,同时支持PCIe Gen-1, Gen-2, Gen-3和SATA 1.5-Gbps, 3-Gbps与6-Gbps接口标准,具有业界最高的信号调理性能,最低的功耗和系统成本,多种配置选择方便使用,主要用在企业服务器,存储设备和路由系统的中继器.本文介绍了DS125BR800A主要特性,框图和应用框图,以及评估板DS125BR800AEVM 主要特性,电路图,材料清单和PCB元件布局图.
The DS125BR800A is an extremely low-power high-performance multi-protocol repeater/redriver designed to support eight channels of PCIe, SAS, and other high-speed interface serial protocols up to 12.5 Gbps. The receiver＇s continuous time linear equalizer (CTLE) provides a boost of up to +30 dB at 6.25 GHz (12.5 Gbps) in each of its eight channels and is capable of opening an input eye that is completely closed due to inter symbol interference (ISI) induced by interconnect medium such as 30in+ backplane traces or 8m+ copper cables, hence enabling host controllers to ensure an error free end-to-end link. The strong linear equalization maximizes interconnect channel extension when the DS125BR800A is placed with the majority of channel loss on the devices input side. Adjustable transmit de-emphasis and output voltage amplitude help to compensate for the remaining channel attenuation on the output side.
When operating in SAS-3 and PCIe Gen-3 mode, the DS125BR800A transparently allows the host controller and the end point to optimize the full link and negotiate transmit equalizer coefficients. This seamless management of the link training protocol ensures system level interoperability with minimum latency. With a low power consumption of 65 mW/channel (typ) and option to turn-off unused channels, the DS125BR800A enables energy efficient system design. A single supply of 3.3 V or 2.5 V is required to power the device.
The programmable settings can be applied easily via pins, software (SMBus or I2C) or loaded via an external EEPROM...