National Instruments 785976-01 PXI High-Speed Serial Instrument

The National Instruments 785976-01 is a high speed serial instrument designed for engineers requiring precise serial protocol validation, interfacing, and testing. The model is also known as the PXIe‑6593. It is equipped with a Xilinx Kintex Ultrascale KU040 FPGA that features 242,400 Look-Up Tables (LUTs), 1,920 DSP48 slices and 21.1 Mb of embedded block RAM. This FPGA architecture provides ample computational power for implementing complex serial protocols.

The module includes 4 GB of onboard DRAM split into two banks of 2 GB each with a physical bus width of 32 bits and a DRAM clock rate of 1064 MHz. When programmed in LabVIEW FPGA, the memory operates at 267 MHz with a 256vbit bus width per bank that offers a maximum theoretical data rate of 17 GB/s (8.5 GB/s per bank). This high speed memory capability is essential for handling large data sets and ensuring rapid processing speeds in demanding test environments. The NI 785976-01 provides eight single ended channels for digital I/O with configurable voltage families ranging from 1.2 V to 3.3 V. The module supports a maximum output toggle rate of 60 MHz with a nominal load. The Molex Nano-Pitch I/O connector is used for these digital interfaces that ensure robust and secure connections in high frequency environments.

The 785976-01 also includes multigigabit transceivers (MGT) for high speed serial communication that support data rates from 500 Mb/s to 16.375 Gb/s. The module features four transmit (TX) and four receive (RX) channels each utilizing Xilinx UltraScale GTH technology. These channels are ACvcoupled for TX and DCvcoupled for RX with input and output impedance set at 100 Ω nominal. The device's QSFP ports are SFF-8436 compliant and accommodate both electrical and optical high speed cables. This serial instrument supports a wide range of generated frequencies in terms of clocking resources from 60 MHz to 1000 MHz and provides three MGT reference clocks. It features SMA connectors for clock inputs and outputs with AC coupling and a nominal output impedance of 50 Ω. The device is housed in a PCI Express Gen-3 x8 form factor requiring 58 W of power and is built to operate within a temperature range of 0 °C to 55 °C.