Details of 3-bit flash ADC (CMOS technology)

[sivamit]

Hi,
can anyone please give me the details of any 3 bit flash ADC(CMOS technology) ?
itz very urgent...
Thank you...

 

[rsrkrishna]

Re: 3 bit flash CMOS ADC

wot exactly u want ??

 

[satyasiva]

Re: 3 bit flash CMOS ADC

wat do u want to know abt it?

 

[dwayne22]

Re: 3 bit flash CMOS ADC

A flash converter is just comparators for each discrete level (for your 3-bit that would mean 7 comparators), and usually a resistor string divider to provide the reference levels for comparison.

The output of the 7 comparators then goes through "thermometer-to-binary" conversion logic to go from the 7 levels to the 3 binary outputs.

If you think a bit about the nature of the output of the comparators as the input analog level varies, you will see why the name of "thermometer."

 

[sunnyee]

Re: 3 bit flash CMOS ADC

hope this can help

 

[micheal_han2000]

Re: 3 bit flash CMOS ADC

sorry, what's the 3 bit flash adc?

 

[yutian]

3 bit flash CMOS ADC

the paper is very good when i read

 

[qqic]

3 bit flash CMOS ADC

some paper in ISSCC is OK

 

[satyasiva]

3 bit flash CMOS ADC

see the book "system design" by wolf. it iwll help u.

 

[isong]

Re: 3 bit flash CMOS ADC

Can you tell me the full name of the book?

see the book "system design" by wolf. it iwll help u.

 

[chocolate85]

3 bit flash CMOS ADC

refer data conversion system design by razavi

 

[satyasiva]

Re: 3 bit flash CMOS ADC

Can you tell me the full name of the book?

see the book "system design" by wolf. it iwll help u.

it is vlsi system design by wolf

 

[Aritra17]

Re: 3 bit flash CMOS ADC

what is the "thermometer-to-binary conversion logic" ??
should i use a xor gate?

---------- Post added at 05:21 ---------- Previous post was at 05:16 ----------

hope this can help

in this .doc file
what kind of encoder is being used??
generally a 8 to 3 bit encoder means

00000100 == 101

but the encoder in this doc shows different results

 

[Aritra17]

Re: 3 bit flash CMOS ADC

for a 3 bit flash adc use 8 resistors(the 1st and the last resistors should be half of the resistance of the rest resistors)
then connect 7 comparators with the reference input through the resistors
the 7comparators outputs should then be feed to thermometer output(xor gates)
the xor outputs should then be feed to encoder inputs
the encoder outputs are the ultimate result for the 3bit flash adc