[goobicii]

is there any thermometer dac that is more than 5bits?          how large will it need to be to get lets say 16bit? can you DIY such thing theoreticaly ifyou had like million dollar budget?

 

[davidsh]

What do you need the DAC for? You mean ADC?

 

[goobicii]

What do you need the DAC for? You mean ADC?

 
PCM music playback..... yes I know what flash ADC is,thing is this technology can work in DAC too its just nobody use it for dac
 
http://www.jameco.com/1/1/39438-ad679jd-1-ch-14-bit-flash-method-adc-parallel-access.html
 
I believe some day I make 16 bit 1 billion khz flash dac

 

[davidsh]

Well, you'd need some 65k comparators and resistors I'd assume?

 

[jcx]

digital potentiometer chips are readily available to 8 bit/256 elements in linear weighting - can get log weighted too for audio volume control
 
 
ADC generally rely on an internal DAC - and for lag a bit in performance because of this dependency
 
and "multibit" delta sigma may add 2^n "unit" sources of I, V, or charge without having a literal "string" of them internally
 
for internals of some "flagship" audio DAC: http://web.archive.org/web/20070118012711/http://www.iet.ntnu.no/~ivarlo/files/School/PhD/Report_audiodac.pdf
 
getting a bit old but then there has been relatively little action at the highest end of monolithic audio DAC in the last few years anyway
 
several chips in that report are ~6 bit
 
one uses "4 bits", 16x? section of dual 8 "unit" IDACs
 
 
the ESS Sabre E9018 in mono mode apparently uses a "9 bit" modulator - but details are sketchy - still 512 unit "somethings" may be involved - if not necessarily a thermometer code ladder
 
 
and there's the ultimate "string" - but requires a unusually low ranging thermometer:

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