EmbDev.net

Forum: Analog Circuits Design ultralow power, narrow band ADC


Author: anhnhamoi ana (Company: hut) (anhnha)
Posted on:

Rate this post
0 useful
not useful
Hi,
I want to design an ADC with these specifications:
Fin = 20MHz
BW= 20MHz
ENOB > 4
Power consumption P < 1mW
Could anyone suggest me some ADC for this kind? I have searched a lot in 
IEEE but there are only two ADC with SAR ADC and time-interleaved ADC.
The ultralow power consumption makes it hard for me to find a 
architecture. I have little experience about this. Kindly help me.

Author: logo (Guest)
Posted on:

Rate this post
0 useful
not useful
Just give the different architectures a try. 4 bits are not that many. 
Start with a flash converter. With 16 comparators and some gates.

Author: Hulk (Guest)
Posted on:

Rate this post
0 useful
not useful
Do you know any logic gate (even an inverter) that operates at 20 MHz 
with
< 1mW??

Probably at 0V supply this is possible...

Author: anhnhamoi ana (Company: hut) (anhnha)
Posted on:

Rate this post
0 useful
not useful
Thanks for the replies!
[QUOTE]Do you know any logic gate (even an inverter) that operates at 20 
MHz
with< 1mW??

Probably at 0V supply this is possible...
[/QUOTE]
That is what I think too. But I have little experience to talk about 
that to my boss. Could you give me a convincing reason for that 
therefore I can pursuade him?
I have searched very much but only found two papers that seem 
appropriate for the requirement.
The requirement about power consumption P< 1mW makes it hard for me.
I attached two papers that I found. Please kindly advise!
http://www.mediafire.com/?bl6bvl3ieesueaa

Author: Hulk (Guest)
Posted on:

Rate this post
0 useful
not useful
With such requirements it seems you have a military customer - that I 
don't like at all.
Otherwise your Boss knows nothing about Electronics!
For Fin = 20MHz you need at LEAST 60M Samples/s ADC!

If you don't want to build your own IC then look for an ADC that you can 
buy. Whatever power it takes you must have!

!! But be aware that you need a high-speed(!) buffer in front of the ADC 
- that consumes a lot more than the ADC itself !!
Try to supply minimal voltage to the converter (~2.5V) and use this for 
reference also.
Look at Analog Devices or Texas Instruments for 4...8 Bit ADC.
See what their power consumption is and tell this your boss.
You won't be a greater genius than this big companies have!

Building something on your own will consume a lot more power.
A solution with descrete comparators will consume 16 x comp. + (20?) x 
logic gates - forget it with 20MHz!!!

Reply

Entering an e-mail address is optional. If you want to receive reply notifications by e-mail, please log in.

Rules — please read before posting

  • Post long source code as attachment, not in the text
  • Posting advertisements is forbidden.

Formatting options

  • [c]C code[/c]
  • [avrasm]AVR assembler code[/avrasm]
  • [code]code in other languages, ASCII drawings[/code]
  • [math]formula (LaTeX syntax)[/math]




Bild automatisch verkleinern, falls nötig
Note: the original post is older than 6 months. Please don't ask any new questions in this thread, but start a new one.