Design Con 2015
Breaking News
Comments
Newest First | Oldest First | Threaded View
mcscopes
User Rank
Rookie
re: Industry View: LeCroy's CTO on the strategic advantage you might be missing
mcscopes   7/30/2012 2:49:43 PM
NO RATINGS
More on the "55db" dynamic range. Assuimg this number means 20*log(largest rms signal/rms noise floor), which is not really explained anywhere, then the rms noise floor in bits is vn_rms=vmax_rms/10**(55/2) or (4096/(2*sqrt2))/10**(55/2)=2.57bits rms. So there will be 2.57bits of rms noise in the baseline. Assuming the pk-pk value is somewhat betwee 8 and 10 times the rms (very arguable) then using 8 the pk-pk bits of noise seen will be 20.6bits. So, with 20+ bits of pk to pk noise, can you resolve (i.e. "see") a perturbation that is only a few bits in amplitude in a single shot aquisition? I couldn't. If you can't, then the noise is not low enough for a 12bit a/d. QED

_hm
User Rank
CEO
re: Industry View: LeCroy's CTO on the strategic advantage you might be missing
_hm   7/28/2012 10:09:52 PM
NO RATINGS
Very interesting interview. I wish to see more high speed 12 and 16 bit oscilloscopes from LeCroy.

mcscopes
User Rank
Rookie
re: Industry View: LeCroy's CTO on the strategic advantage you might be missing
mcscopes   7/27/2012 7:01:23 PM
NO RATINGS
My bad; 16:1 is right. However, it's an overstatement to say that a "normal" 8 bit scope has about 40db of SNR because this is a huge function of bandwidth. Many 2 to 4 GHz oscilloscopes have a SNR better than 40db, and when used in high resolution mode that limits the BW down to HRO BW's, can easily equal the 55db of the HRO. Now you have effectively a "12 bit" scope at lower BW and a higher BW scope at "8 bits". Additionally, I think you'd find that 55db SNR for a 12bit system is still kind of marginal; you'd get something like 20+ bits of pk-pk noise in the baseline.

dave57
User Rank
Rookie
re: Industry View: LeCroy's CTO on the strategic advantage you might be missing
dave57   7/27/2012 10:57:35 AM
NO RATINGS
You are absolutely correct that more bits without a better signal path design could be useless. By my calculation 4 extra bits would mean 1/16 of the noise, not 1/32. A factor of 16 is about 24db. A "normal" 8 bit scope has about 40db SNR - although a few are somewhat better. The LeCroy HROs have about 55db SNR. That's just about what you'd expect for 4 extra bits. You should take a look at one... I think you'll be impressed.

mcscopes
User Rank
Rookie
re: Industry View: LeCroy's CTO on the strategic advantage you might be missing
mcscopes   7/26/2012 10:00:23 PM
NO RATINGS
There is undoubtedly a certain knee jerk appeal to more bits in an oscilloscope. However, more bits without a comensurate lower noise floor is not useful. Realistically for every bit increase in a digitizer, there ought to be a 2:1 decrease in noise level, so check to see if a 12 bit scope has 1/32 of the noise floor of an 8 bit scope. I think you'll be disappointed....

sharps_eng
User Rank
Rookie
re: Industry View: LeCroy's CTO on the strategic advantage you might be missing
sharps_eng   7/26/2012 6:46:56 PM
NO RATINGS
Hear hear for the PSU designers! (If you know how to design PSUs and your bosses don't appreciate you then go work for a PSU design company). More than 12 bits at any speed is a threshold, suddenly you have to consider temperature and component variations. Not everyone needs to go at Croy speeds but they themselves have to so you can trust what their instrument is telling you. Engineers generally work better with instruments and tools they can be proud of - and vice versa. I am seeing some good value Croys on sale right now, maybe its time for a treat!



Most Recent Comments
sempaiscuba
 
mithrandir
 
sempaiscuba
 
sempaiscuba
 
sempaiscuba
 
sempaiscuba
 
sempaiscuba
 
sempaiscuba
 
sempaiscuba
Top Comments of the Week
Flash Poll
Like Us on Facebook

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
EE Life
Frankenstein's Fix, Teardowns, Sideshows, Design Contests, Reader Content & More
Max Maxfield

Max's BADASS Display: A Comedy of Errors
Max Maxfield
5 comments
Good grief -- where does the time go? I first determined to build my Bodacious Acoustic Diagnostic Astoundingly Superior Spectromatic (BADASS) display way back in the mists of time we used ...

<b><a href=Betajet">

The Circle – The Future's Imperfect in the Present Tense
Betajet
5 comments
The Circle, a satirical, dystopian novel published in 2013 by San Francisco-based writer Dave Eggers, is about a large, very powerful technology company that combines aspects of Google, ...

Martin Rowe

Make This Engineering Museum a Reality
Martin Rowe
Post a comment
Vincent Valentine is a man on a mission. He wants to make the first house to ever have a telephone into a telephone museum. Without help, it may not happen.

Rich Quinnell

Making the Grade in Industrial Design
Rich Quinnell
16 comments
As every developer knows, there are the paper specifications for a product design, and then there are the real requirements. The paper specs are dry, bland, and rigidly numeric, making ...

Special Video Section
The LT8640 is a 42V, 5A synchronous step-down regulator ...
The LTC2000 high-speed DAC has low noise and excellent ...
How do you protect the load and ensure output continues to ...
General-purpose DACs have applications in instrumentation, ...
Linear Technology demonstrates its latest measurement ...
10:29
Demos from Maxim Integrated at Electronica 2014 show ...
Bosch CEO Stefan Finkbeiner shows off latest combo and ...
STMicroelectronics demoed this simple gesture control ...
Keysight shows you what signals lurk in real-time at 510MHz ...
TE Connectivity's clear-plastic, full-size model car shows ...
Why culture makes Linear Tech a winner.
Recently formed Architects of Modern Power consortium ...
Specially modified Corvette C7 Stingray responds to ex Indy ...
Avago’s ACPL-K30T is the first solid-state driver qualified ...
NXP launches its line of multi-gate, multifunction, ...
Doug Bailey, VP of marketing at Power Integrations, gives a ...
See how to ease software bring-up with DesignWare IP ...
DesignWare IP Prototyping Kits enable fast software ...
This video explores the LT3086, a new member of our LDO+ ...
In today’s modern electronic systems, the need for power ...