PXIe modules continuously replay signals at high output rate
Arbitrary waveform generators (AWGs) from Spectrum are designed for automated testing where fast, accurate electronic signal generation is required. The M4x series of PXIe AWGs are based on the modular PXIe instrumentation standard. The M4x series is made up of five modules that provide one, two or four channels.
Each channel is equipped with a 16bit DAC. Depending on the model, maximum clocking rates are 625Msample/s or 1.25Gsample/s. The combination of high resolution and fast clocking rates makes them suitable for generating precise and flexible wave shapes with frequency content from DC to 400MHz, claims the company.
The dual width, 3U AWGs feature a PXIe x4 Gen2 interface that allows waveform data to be transferred to the module’s 4Gbyte of on-board memory at speeds up to 1.4Gbyte/s. They are PXIe-compliant and can be used in any PXIe or PXI hybrid chassis. Support is also provided for chassis distribution features such as the PXIe/PXI reference clock, star-trigger and trigger bus.
To generate long and complex waveforms, the AWGs include operating modes such as single-shot, loop, FIFO, gating and sequence replay. In FIFO mode, the instruments can stream data continuously from PC memory to the AWG memory over the PXIe interface. According to the company, the generators can even output signals while new waveform data is being sent to the on-board memory. The combination of operating modes, fast data transfer and the large on-board memories, make the M4x series among the most flexible on the market, the company believes.
Each channel is clocked using a precision PLL control system that can be generated internally or from an external clock or reference. Three front-panel, multi-purpose I/O connectors allow access to synchronous marker outputs, asynchronous digital I/O lines, the trigger output, the run and arm status and the PLL reference clock.
The M4x AWGs are designed to output signals that emulate those found in the real world, delivering programmable output levels from ±200mV to ±4V (±5V for 625Msample/s models) into high-impedance and ±100mV up to ±2V (±2.5V for 625Msample/s models) for 50Ohm termination. Using 16bit DAC, the AWGs also allow fine signal details to be generated. They deliver dynamic performance with SNR up to 72dB, spurious free dynamic range (SFDR) up to 98dB and noise spectral density (NSD) at -150dBm/Hz.
The generators are shipped with a host of software tools so users can create control programs with almost any popular programming language, including C++, Visual Basic, VB.NET, C#, VisualJ#, Delphi, Java and Python code. Third party software support is also provided for LabVIEW, LabWindows and MATLAB for users not wanting to write software.
The company also offers its SBench6-Pro software that lets users control all of the AWG’s operating modes and hardware settings from a simple, easy-to-use, GUI. The software has a host of built-in features for waveform creation, data analysis and documentation. These include the EasyGenerator function for producing standard wave shapes such as sine, rectangular, triangle, saw-tooth, SINC and DC. Waveforms can also be created from equations, imported from other devices (such as digitisers and oscilloscopes) or other software programs. SBench6 allows data import and export in the most popular formats such as ASCII, binary and WAV.