Global Sources
EE Times-Asia
Stay in touch with EE Times Asia
EE Times-Asia > T&M

LeCroy's scopes get unique mixed-signal outboard pods

Posted: 04 Mar 2005 ?? ?Print Version ?Bookmark and Share

Keywords:oscilloscope? lecroy? ms-32? mixed signal optionsScorpion? wavesurfer 400?

Oscilloscope vendor LeCroy Corp. is dishing up a technically innovative product with the release of its MS-32 Mixed Signal Option, code named The Scorpion. Although the Scorpion plug-in adjunct is suitable only for LeCroy oscilloscopes, it does give the company's existing 350MHz and 500MHz 4-channel WaveSurfer 400 and 4-channel 500MHz to 2GHz waverunner 6000a instruments 32 channels of digital input.

With that, LeCroy competes with agilent technologies' recently introduced 6000 Series mixed-signal portable scopes with their 16 digital input channels and (deeper, i.e. longer) 8-Mpoint memories, as well as competing scopes from Tektronix (with its TDS3000B series) and competitor Yokogawa (with its DL7400 mixed-signal scopes).

Uses USB
Not immediately gleaned from LeCroy's press statement is that the MS-32 is an outboard unit that relies on USB 2.0. Contemplating peripherals such as the MS-32 digital fixture, LeCroy equipped its Windows XP-based WaveSurfer 400 and WaveRunner 6000A scopes with 480Mbps serial USB 2.0 ports on their front panels.

The MS-32 makes use of those ports, as well as the separate trigger input BNC connectors right next to the USB ports. Connection is rather straightforward, and the pod's small size (it measures 9.6-by-16-by-3cm in size less input leads) complements the host oscilloscopes' slender footprints.

Module packs memory
Significantly, the MS-32 brick also packs the digital subsystem's deep memory of 1Mpoint/channel. The 32Mb that reside in the MS-32 complement the 24MB/channel already in the host oscilloscope's analog channels (assuming a WaveRunner 6000A in its 2-channel mode with very long memory).

Although not as long as Agilent's 8-Mpoint deep memory, LeCroy says that most of the purchasers of its scopes want more channels, not necessarily deeper memories. "Although many users say that 1-Mpoint per channel is capture is great," notes LeCroy director of product management Dr. Michael Lauterbach, "more important to them is to have 32 digital channels."

Most users of moderate bandwidth mixed-signal scopes are working with designs using embedded controllers, and that's where mixed-signal instruments such as LeCroy's new MS-32 Scorpion give you the ability to observe multiple analog signals that are time-coincident with a system's numerous lines of digital I/O.

"With 32 digital channels," adds Lauterbach, "you can make one connection and capture everything. A lot of users say that with only 16 digital channels, they can't see all the signals needed to in order to understand a mixed-signal problem."

The MS-32 will let you look at linear signals from amplifiers, comparators and sensors, for example, at the same time that you're scrutinizing address, control, and data lines, or peripheral serial signals. The MS-32 will let you capture up to 125MHz digital clocks, too. You can capture these signals into the MS-32's memory, or set up digital or analog trigger conditions.

Sampling at 1kS/s to as fast as 500MS/s, logic threshold levels can be set to accommodate TTL, ECL and CMOS logic (including CMOS operating at 2.5V, 3.3V and 5V), as well as PECL. As you'd expect, you can also define your own logic thresholds.

Digital channel grouping can also be defined. Each of four digital groups can use any combination of the 32 digital input lines. Groups can be displayed as individual lines, or collapsed into a bus view.

For triggering, you can either choose the analog section's trigger or establish a digital trigger. For the latter, you can set up your triggering as logic type, logic bus, or interval triggering. Logic setup can accommodate up to 32 digital lines, with any combination of 0, 1 or X.

Individual line trigger set up
In addition, a rising edge, falling edge or Either Edge condition can be set up (multiple edges are OR combined). This gives you the ability to create simple or complex digital trigger conditions. Each digital line can be individually set up.

If you choose the MS-32's logic bus format, the digital lines can be defined in hex.

If you go with interval triggering, you can define a single digital line, or the slope, condition, and time period in which a second occurrence of that digital line should occur. You can set the conditions to be greater or less than, in-range, or out-of-range. Accuracy is within 1 digital sample (based on the sample rate).

The Scorpion's sting
If you consider the reasonable price tag of the MS-32, and especially the fact that LeCroy's 4-channel WaveRunner 6000A can work out to 2GHz, it's apparent that the company is going to give Agilent, Tektronix, and Yokogawa a runs for their money in the moderate bandwidth mixed-signal category.

- Alex Mendelsohn

Article Comments - LeCroy's scopes get unique mixed-sig...
*? You can enter [0] more charecters.
*Verify code:


Visit Asia Webinars to learn about the latest in technology and get practical design tips.

Back to Top