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High-speed digitizers acquire analog and digital signals simultaneously | Spectrum

Addition module helps with mixed signal testing
Spectrum Instrumentation has announced a new digital input option (M4i.44xx-DigSMA) for its popular high-speed and high-resolution series of PCIe digitizers. The option consists of an additional module that sits beside the existing digitizer card to provide 8 additional digital input lines. The digital input module shares a common clock and trigger with the base card so that both the digital and analog inputs are fully synchronous. This makes the combination ideal for a wide variety of mixed signal testing applications. The option is available for all digitizer models of the "44"-series with up to 500 MS/s and two or four analog inputs. More analog channels can also be acquired by linking up to eight digitizers together with Spectrum's unique Star-Hub clock and trigger distribution system.

Flexible Digital Inputs

The new M4i.44xx-DigSMA digital input option has a separate PCIe faceplate, occupying an additional PCIe slot, with 8x SMA type connector. Designed for versatility, each input has an impedance of 10 kOhms (to 3.3 V). This allows the inputs to handle 3.3 V LVTTL signals with input voltage levels between -0.5 V and +4.0 V. The digital input bandwidth is 125 MHz and software selection enables both synchronous and asynchronous acquisition modes.

When using the digital input option, the digital data is stored inside the analog samples by reducing a channel's resolution. This allows phase synchronization of both the analog and digital signals, as the one-bit digital signals are placed in the high order bits of the analog waveforms. As an example, if eight digital channels are in use, then the resolution of the analog channels would be reduced from 16 to 14 bits and two of the digital signals would be appended to each analog channel of a four-channel digitizer.

Match the digitizer to your application

The Spectrum M4i.44xx series of PCIe digitizer cards consists of eight different models. Users can select from versions that have either two or four analog channels and sampling rates of 180 or 250 MS/s, with 16-bit resolution, or higher speeds of 400 or 500 MS/s, with 14-bit resolution. The digitizer cards of the "44" series are fully equipped with extensive analog signal conditioning (6 input ranges, selectable input impedance, offset, etc.) and advanced triggering capabilities. The acquired data can be stored in a generous 2 GSamples of on-board memory or transferred to a PC in a variety of memory efficient read-out modes, including FIFO streaming, at rates up to 3.4 GB/s.

The cards are also packed with features to make them easy to integrate into any test setup. For example, they have additional front panel connections that include two external trigger inputs, an external clock reference input, clock output and three general purpose I/O lines that are available for asynchronous I/O operations. They come complete with software as well as all the tools necessary to work in virtually any system; whether it be embedded in an automated testing rig for electronic components or utilized as the key data acquisition device in science, communications, power, aerospace or medical applications.

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