Jitter Transceivers from National Semiconductor Deliver 30 Percent More Backplane and Cable Reach

(Product News, 2 Jul 2009)

National Semiconductor Corp. introduced two highly energy-efficient, quad transceivers that extend backplane and cable reach up to 30 percent farther than competitive devices. These PowerWise signal conditioning devices drive high-speed signals in data center servers and storage area networks (SANs). The DS50PCI401 is PCI-SIG-approved to the PCI Express (PCIe) Gen1 (2.5 Gbps) and Gen2 (5 Gbps) specifications, while the DS64BR401 supports both 3 Gbps and 6 Gbps SATA/SAS specifications, along with other high-speed signaling standards such as XAUI, serial Rapid IO (sRIO) and Fibre Channel.

The DS50PCI401 four-lane, bidirectional PCIe transceiver provides both adjustable receive equalization and transmit de-emphasis, along with the industry’s lowest power at 190 mW typical per lane. In addition, it supports a selectable low-power state as well as power-down of individual lanes. The DS50PCI401 compensates for transmission medium losses, reducing deterministic jitter on eight transmission channels. It equalizes more than 10 meters of PCIe cable or 40 inches of FR-4 printed circuit board (PCB) at transmission rates up to 5 Gbps. At seven meters of PCIe cable equalization, the DS50PCI401 achieves less than 0.10 unit intervals (UI) of residual jitter at the equalizer output. This extended reach enables the use of lower-cost, thinner (higher gauge) PCIe cable.

The DS50PCI401 offers a unique automatic rate detect feature that adjusts the output signal conditioning to achieve the maximum benefit at Gen1 and Gen2 data rates. In addition, the DS50PCI401 supports PCIe specific out-of-band (OOB) signaling such as transmit idle, receive detect and beacon signal pass through.
The DS64BR401 four-lane, bidirectional SATA/SAS transceiver provides both adjustable receive equalization and transmit de-emphasis, and has undergone extensive interoperability testing with third-party host and target devices. It equalizes up to 10 meters of SATA/SAS cable or 40 inches of FR-4 printed circuit board (PCB) at transmission rates up to 6.4 Gbps, with less than 0.25 UI of residual jitter at the equalizer output.

With a typical power consumption of 200 mW typical per lane, the DS64BR401 supports OOB signaling with approximately 3 ns typical of envelope distortion, ensuring compatibility with the SATA/SAS specification. It also offers an adjustable voltage output differential of 600 mV peak-to-peak (p-p) to 1200 mV p-p. The DS64BR401 provides automatic power management on an individual lane basis via an SMBus interface.

The DS50PCI401 and DS64BR401 are the latest additions to National’s growing family of quad-, dual- and single-channel signal conditioning products. National fabricates these devices on its high-performance silicon-germanium (SiGe) BiCMOS-8 process technology.