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Where to get high speed ADC's and DACs

Started by RobertMacy September 1, 2013
Where do I get 24 bit high speed ADC and DAC systems out to 10MHz?

Or, turn around how much digitization can I get out to 100MHz today? 20  
bits?
On Sun, 01 Sep 2013 09:33:15 -0700, RobertMacy <robert.a.macy@gmail.com> wrote:

>Where do I get 24 bit high speed ADC and DAC systems out to 10MHz? > >Or, turn around how much digitization can I get out to 100MHz today? 20 >bits?
This is about right: http://www.linear.com/designtools/hsadcs.php We use their 250 MHz, 12-bit LVDS ADC and it's pretty good. https://dl.dropboxusercontent.com/u/53724080/PCBs/ESM_rev_B.jpg A 20 or 24-bit ADC, at 100 MHz, probably isn't useful. Wideband noise would trash a lot of LSBs. -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links VME analog, thermocouple, LVDT, synchro, tachometer Multichannel arbitrary waveform generators
On 9/1/2013 12:33 PM, RobertMacy wrote:
> Where do I get 24 bit high speed ADC and DAC systems out to 10MHz? > > Or, turn around how much digitization can I get out to 100MHz today? 20 > bits?
Sure thing. Just use two 10-bit ADCs and put a 60 dB pad in front of one of them. ;) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 USA +1 845 480 2058 hobbs at electrooptical dot net http://electrooptical.net
On Sun, 01 Sep 2013 13:23:55 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

>On 9/1/2013 12:33 PM, RobertMacy wrote: >> Where do I get 24 bit high speed ADC and DAC systems out to 10MHz? >> >> Or, turn around how much digitization can I get out to 100MHz today? 20 >> bits? > >Sure thing. Just use two 10-bit ADCs and put a 60 dB pad in front of >one of them. ;) > >Cheers > >Phil Hobbs
It's cheaper to concatenate the output of a 10-bit ADC with a 10-bit random sequence generator. -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links VME analog, thermocouple, LVDT, synchro, tachometer Multichannel arbitrary waveform generators
On Sun, 01 Sep 2013 09:44:40 -0700, John Larkin  
<jjlarkin@highnotlandthistechnologypart.com> wrote:

> On Sun, 01 Sep 2013 09:33:15 -0700, RobertMacy <robert.a.macy@gmail.com> > wrote: > >> Where do I get 24 bit high speed ADC and DAC systems out to 10MHz? >> >> Or, turn around how much digitization can I get out to 100MHz today? 20 >> bits? > > This is about right: > > http://www.linear.com/designtools/hsadcs.php > > > We use their 250 MHz, 12-bit LVDS ADC and it's pretty good. > > https://dl.dropboxusercontent.com/u/53724080/PCBs/ESM_rev_B.jpg > > A 20 or 24-bit ADC, at 100 MHz, probably isn't useful. Wideband noise > would > trash a lot of LSBs. > >
John, You have no idea how much I respect Linear and their products. but I was talking about 20+bits not the insignificant 12 bit range. [I recently did 18 bits at 500MHz - Jim Williams would have been proud, NEVER AGAIN!!! From simulations, I need 20+ bits, else quantization noise eats me alive!
On Sun, 01 Sep 2013 10:23:55 -0700, Phil Hobbs  
<pcdhSpamMeSenseless@electrooptical.net> wrote:

> On 9/1/2013 12:33 PM, RobertMacy wrote: >> Where do I get 24 bit high speed ADC and DAC systems out to 10MHz? >> >> Or, turn around how much digitization can I get out to 100MHz today? 20 >> bits? > > Sure thing. Just use two 10-bit ADCs and put a 60 dB pad in front of > one of them. ;) > > Cheers > > Phil Hobbs >
PHIL! Not funny! well maybe, a bit, still LOL
On 9/1/2013 1:47 PM, RobertMacy wrote:
> On Sun, 01 Sep 2013 10:23:55 -0700, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > >> On 9/1/2013 12:33 PM, RobertMacy wrote: >>> Where do I get 24 bit high speed ADC and DAC systems out to 10MHz? >>> >>> Or, turn around how much digitization can I get out to 100MHz today? 20 >>> bits? >> >> Sure thing. Just use two 10-bit ADCs and put a 60 dB pad in front of >> one of them. ;) >> >> Cheers >> >> Phil Hobbs >> > > PHIL! Not funny! well maybe, a bit, still LOL
Well, if we generously assume that an ADC that fast could have a 5V input range, 1 LSB at 20 bits is 5 uV, and the quantization noise is 1/sqrt(12) times that, or 1.4 uV. In a 100 MHz bandwidth, that's 140 pV/sqrt(Hz). In real life, the input structure would have to be several times faster than that in order to settle to that accuracy in the time available, putting the maximum input noise down in the 50 pV/sqrt(Hz) range, not counting the effects of input capacitance. Good luck with that. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 USA +1 845 480 2058 hobbs at electrooptical dot net http://electrooptical.net
On Sun, 01 Sep 2013 13:23:55 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

>On 9/1/2013 12:33 PM, RobertMacy wrote: >> Where do I get 24 bit high speed ADC and DAC systems out to 10MHz? >> >> Or, turn around how much digitization can I get out to 100MHz today? 20 >> bits? > >Sure thing. Just use two 10-bit ADCs and put a 60 dB pad in front of >one of them. ;) > >Cheers > >Phil Hobbs
But not nearly as sexy. Way back in the design days for the L1011, I suggested a seat-audio system made up of two 8-bit DAC's, one basically volume riding, and the other the "detail". Demonstrated it. Sounded great. Rejected in spite of how inexpensive it was. They went with a much more expensive 12-bit DAC. ...Jim Thompson -- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | San Tan Valley, AZ 85142 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.
On 9/1/2013 11:33 AM, RobertMacy wrote:
> Where do I get 24 bit high speed ADC and DAC systems out to 10MHz? > Or, turn around how much digitization can I get out to 100MHz today? 20 > bits?
You can get true 24 bit performance in a bandwidth of somewhat like 50Hz (current state of art). For 100 MHz bandwidth, you just have to parrallel 2000000 frequency split channels. VLV
On Sun, 01 Sep 2013 11:20:55 -0700, Jim Thompson  
<To-Email-Use-The-Envelope-Icon@on-my-web-site.com> wrote:

>> ..snip... > Way back in the design days for the L1011, I suggested a seat-audio > system made up of two 8-bit DAC's, one basically volume riding, and > the other the "detail". > > Demonstrated it. Sounded great. Rejected in spite of how inexpensive > it was. They went with a much more expensive 12-bit DAC. > > ...Jim Thompson
Don't get me started on 'closed mindedness'! Back around 1966, I designed the hardware computer interface for L1011. Going from that environment [aerospace and autopilots] to HP' RF/Microwave Lab, noted for their conservative designs, was like being thrust into the sloppiest garage designers I'd ever seen! Imagine what it was like to go from that into coin-opeated electronic games!