LXI digitizers for multi-channel HF signal capture & analysis

February 27, 2017 // By Graham Prophet
Offering fully synchronous Gsample/sec acquisition on up to 24 channels, Spectrum (Grosshansdorf, Germany) has introduced its DN6.22x series of LXI digitizers, developing the company’s digitizerNetbox products by adding eight models that feature high-channel count, fast sampling rates and wide bandwidth.

The entry-level DN6.221 models offer versions with 12, 16, 20 and 24 channels, with each channel capable of sampling electronic signals at rates up to 1.25 Gsample/sec. The top-of-the-line DN6.225 series increases performance by allowing up to 12 channels to sample at 2.5 Gsample/sec or 6 channels at 5 Gsample/sec.


The digitizerNetbox products are complete instruments that include all the tools necessary to capture, digitize and analyze signals, and operate connected to a host computer (e.g. laptop or workstation) running Spectrum's SBench 6 software. Standard with every unit, SBench 6 allows the user to control all the digitizer’s operating modes and hardware settings from one graphical user interface.


The software has features for waveform display, data analysis and documentation. Acquired and analyzed waveforms can be stored and exported to other devices or other software programs in a variety of formats such as MATLAB, ASCII, binary and wave.


Each channel of a DN6.22x series digitizer features its own ADC, acquisition memory (1 GSample/channel) and independent signal conditioning circuitry. The ADCs are clocked synchronously to ensure that inter-channel timing measurements can be made with the best possible accuracy as well as maintaining a constant phase relationship.


Front-end amplifiers allow input signals to be correctly scaled, so that the digitizers can utilize the ADC’s complete 8-bit dynamic range. Programmable full-scale ranges (into 50Ω termination) go from ±200 mV up to ±2.5V or optionally from ±40 mV up to ±500 mV. Signal conditioning also includes AC/DC coupling and programmable input offset.


The DN6.221 models, with 1.25 Gsample/sec sampling rate, are matched with amplifiers that deliver over 500 MHz of bandwidth, while the DN6.225 models increase this to 1.5 GHz. The combination of fast sampling rate, wide bandwidth and long acquisition memory enables the digitizers to capture long, complex, high frequency signals. It also makes it possible to characterize and measure fast events that go down into the nano- and