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Need help on a d/a and a/d converter

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diegoisra

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I need to design a d/a and a/d converter, and i do not know which is the easyest way to do it.
 

You need find some information about ADC and DAC in this site.

There are some type of signal converter like as oversamples, delta-sigma ....
Read the book: Data converter in communication (download free in this site) or some other book.
Many document discusses about this topic. But
actually, you must determines how many bits for data converter, operation frequency, required SNR,which CMOS technology is used for design ...
If you only need simulation, as my opinion you can use Matlab it is convenience.
 

Refer to Analog IC Design by David Martin.
 

Easiest way? easiest is flash adc (2^n comparators, each comparing Vinput to it's own tap on the resistor divider) easiest dac is R-2R dac. google either of those terms and you will find a lot of info.

both flash adc and r-2r dac have significant drawbacks due to the fact that they are "brute force" approaches. heavy advances have been made in 1) reducing number of ADC comparators from 2^n to much lower. and 2) improving quality of DAC output (INL/DNL) including glitch energy when transitioning codes.

but... each method has it's place. no adc is faster than flash, so the world's fastest adc are still flash (with 65,536 comparators for 16 bit! haha!) and no dac is simpler than r-2r - even maxim and adi use r-2r still.

so it's up to you. a lot of learning is needed to master each new tier of complexity - what performance do you need? your first addac is not going to break any world's records anyway, so the simpler the better i say. at least that way you have a good chance it works first time!
 

also you can find books on the bone hub that discuss adc in detail
 

I am not familiar with this forum,
So can you tell me how to download 'Data converter in communication'.

hoangthanhtung said:
You need find some information about ADC and DAC in this site.

There are some type of signal converter like as oversamples, delta-sigma ....
Read the book: Data converter in communication (download free in this site) or some other book.
Many document discusses about this topic. But
actually, you must determines how many bits for data converter, operation frequency, required SNR,which CMOS technology is used for design ...
If you only need simulation, as my opinion you can use Matlab it is convenience.
 

Multislope intergrator ADC,up-to 28 bits resolution. Does somebody know about it in this forum?
 

I think it should depends on the applciation of ADC you use.

the concept is easy, but te design maynot be so easy.
 

As my friend said in the previous messages , it depends on the application . There are many types of A/D and D/A .They differ in many ways, speed of conversion and the construction .

Speed of conversion is the most important factor to be consider when chosing A/D or D/A. The A/D flash type is the fastest one .

The easy way to undersatand their appliction is the modem in the computer which is used to connect the internet for the dial-up type . It convers the signal from analoge (phone line ) to digital (into the computer ) since the computer deals only with digital signals (clocks) .The vise cersa also applicable .

Many books are availble at amazon.com and too many sites in the internet can be found which have huge information and description about A/D and D/A .
 

Both ADC and DAC are classified as speed and resolution. Flash type is fast but low bits (should be 5-bits or less, since it will use 2^n comparator for comparison to generate the bit. Besides the analog side(comparator/opamp), there are some digital block to decode to the real bit and other block to prevent wrong results. High resolution ADC/DAC (usually 10 bit up) are usaully accoplished through low speed, eg. oversample sigma-delta ADC/DAC. In one word, use time to realize resolution. In this kind of topology, two sections are focused, modulator and decimation filter. Modulator generates the bits streams, decimation to take out the bit for the results. In bewteen there are pipe-line based ADC, current-steering DAC, SAR based ADC, folding based ADC.

To design good ADC/DAC, a good opamp is need. Speed, linearity, and noise should be trade off when designing OPAMP. It's a big topic. Hope someone else continue.
 

Read Razavi's book and some IEEE paper about it.
 

hi electronrancher can u tell me how to join the bone hub because i need the books which have detailed description of adc
 

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