A look at a simplified block diagram for one of Gage Applied Technologies's newest CompuScope 14200 PCIbus plug-ins reveals a straightforward system architecture (sans software).
What the block diagram doesn't reveal is Gage's selection of leading-edge components that impart the sparkling specs these products enjoy. It also doesn't imply that you can build up multi-board systems using multiple 14200 boards, nor does it say anything about PC-hosted software. More on all of this in a moment.
Click for larger block diagram
In a multi-board system, the cards can operate either in master/slave modes, or independently. In the former case, you can fit up to eight of these PCI v.2.2 cards. If they're running independently, you're limited only by the size and electrical constraints of the PCIbus backplane in your PC.
Speaking of PCs, you'll need at least a Pentium-II machine, clocking at 500-MHz, with a 33-MHz or 66-MHz bus, to support a full-length 14200 CompuScope. Your machine will need at least 128 Mbytes of DRAM, and 100 Mbytes or so of free hard disk capacity.
A Plug-and-Play Peripheral
Operating as a Windows Plug-and-Play peripheral, a 14200 CompuScope operates in a bus-mastered mode, with scatter-gather supported in driver software.
The card's 14 bits (11.8 bits ENOB) of resolution, and 100-MHz bandwidth is partially attributable to the use of an FPGA to capture a great deal of logic in the back-end datapath. That, coupled with the 32 Msamples of memory, or even the optional 1 Gsample of memory, makes this power-managed digitizer a screamer, to say the least, as well as a very accurate system.
At the front-end of the card, you can feed your signals in either at 50-ohms (as per the press statement), or into a diode-protected high-Z input (1-Mohm shunted by 40-pF), with either AC or DC coupling. In use, the card will give you a spurious-free dynamic range (SFDR) of 71 dB, with a 74-dB signal-to-noise (SNR) ratio spec.
The AC coupled bandwidth extends from 10-Hz to 80-MHz. If you go with direct coupling, you'll see the card's full bandwidth from DC out to 100-MHz (using the 50-ohm input impedance). This response is flat to within ±1-dB over 75% of the bandwidth spec. The card's direct-to-A/D sampling mode, which is DC coupled, provides a bandwidth out to 300 MHz.
With specs like that, you'll also enjoy very low phase distortion. Gage claims that it will be no greater than one percent over 75-percent of the bandwidth, however the company is in the process of characterizing this response right now.
Like A Bench Scope
Operated like a conventional oscilloscope, a Model 14200 gives you six ranges of full-scale inputs. These include ±100-mV, ±200-mV, ±0.5-V, ±1-V, ±2-V, and ±5-V. Analog triggering can be from either channel, from an external source, or from a point in software. As you'd expect with a bench scope, you can set a trigger's slope and sensitivity. You can also invoke a post trigger of up to 256 points.
Gage's press statement mentions the company's existing GageScope oscilloscope software. It's what lets one or more of these 14200 cards acquire, archive, and analyze signals.
The software also lets you readily set up a 14200 though your PC's user interface. Using GageScope, there's no programming, and no need to draw diagrams graphically. You just click your mouse and you're all set to operate just like a bench scope.
GageScope lets you automatically measure and display most waveform parameters, so that you can quickly determine things such as frequency and amplitude, or measure a signal's rise- and fall-times, or pulse width. The software will also do signal averaging. The averaging can extend to an unlimited number of acquisitions, too, which can be used to eliminate the effects of random noise. Co-adding (averaging without dividing the result) is also available.
Thanks to being PC hosted, the software also lets you automatically save your results. GageScope's AutoSave feature is great for unattended transient capture, for example. In that capacity, it will save transients to disk and date- and time-stamp them. The AutoSave feature also saves both pre- and post-trigger data.
The software can also process captured signals to derive frequency domain information from them. Equipped with fast Fourier transform (FFT) algorithms, GageScope can do a 4-million point FFT. With that you can enjoy multi-channel spectral analysis, and get simultaneous views of both the time-domain and frequency-domain.
Finally, GageScope provides lots of math processing. This supports things such numerical differentiation and integration, and auto-correlation and cross-correlation. The number crunching can also support creation of sub-channels based on signal features and triggers.
Of course, you can also transfer data to downstream analysis packages such as MatLab, MathCad, and LabVIEW. You can also export screen images into other popular Windows applications, which can be useful for generating documentation or for doing spreadsheet analyses.
For more information, contact Gage Applied Technologies, Inc., 2000, 32nd Avenue, Lachine, QC, H8T 3H7, Canada. Phone: 1-800-567-GAGE. Fax: 1-800-780-8411.
Learn more at Gage's Web site.