how to test a flash adc

[niket_jmd]

i have made a flash adc in mentor tools its 6 bit nd flash architecture

so how to check the specification of adc
i mean INL and DNL etc how to make these tests??

 

[dachuan315]

you can input a ramp signal. ideal number is a code display times with ideal condition. active number is a code display times with active condition.
DNL(i)=(ideal number - actvie number)/ideal number
INL(i)=∑DNL(0：i)

 

[niket_jmd]

thnks...............and wht abt sndr and snr ..........i mean dynamic chracterstic

 

[rajashekar333]

Hi niket,
I am working on same design of TIQ flash ADC using mentor graphics tools.how did u find the speed of adc,can you please give me ur specifications ,how speed it is workin.
thaks a lot in advance.
Regards,
Raj

 

[niket_jmd]

finding speed is simple as we can find the code trasition delay.......with respect to clock........generally sndr and snr falls and which defines the max inp frequency........stilll i have to check it

 

[windgone0204]

you can give a sin signal,then you can analyse the output datas with spice-explore:converte the output datas to digital signal,then converte the digital signal to analog signal,finaly u can get the sndr,snr,sfdr,enob,etc. you also can refer to the spice-explore help.

 

[rajashekar333]

Hi, I got Spice simulation results for 6 bit TIQ ADC for sinusoidal input.But i could not get an idea to find INL,DNL,SNR,SNDR and EDOB.How to find all these in Matlab and how can i give spice outputs as input in Matlab.can you please explain for same in Detail.Thanks in adv.

 

[muralicrl]

Hi,

Kindly see the attachment, it may be useful to you,

If you need more details, don't hesitate to contact me.

Regards,

N.Muralidhara
CRL-BEL

 

[southwave]

Can anyone show how to get SFDR an SNDR in detail?

 

[lwjbh]

SFDR:10log(P_signal/P_maxharmonic)
SNDR:10log(P_signal/(P_harmonic+P_niose))

 

[southwave]

SFDR:10log(P_signal/P_maxharmonic)
SNDR:10log(P_signal/(P_harmonic+P_niose))

ThanKs
I mean how to use cadence's DFT function to measure SFDR and SNDR?