AnsweredAssumed Answered

ADC Speed

Question asked by Lothar Eichelberger on Nov 1, 2012
Latest reply on Dec 11, 2012 by Lothar Eichelberger

Hi there


I' m using a tower modul with a K20 72MHz MCU and i would like to use the ADC.

I've got the following questions:


CFG2[ADHSC] is used to configure a higher clock input frequency. This will allow

faster overall conversion times. To meet internal ADC timing requirements,

CFG2[ADHSC] adds additional ADCK cycles. Conversions with CFG2[ADHSC]=1 take

two more ADCK cycles. CFG2[ADHSC] must be used when the ADCLK exceeds the

limit for CFG2[ADHSC]=0.

From which ADCK upwards it must be set? I didnt found that in the manual


After a reset what is the normal clock speed of everything?

Something like that:

Option 2:

Clock Frequency

Core clock 72 MHz

System clock 72 MHz

Bus clock 36 MHz

FlexBus clock 36 MHz

Flash clock 24 MHz


Am I right with that? Thanks in advance for your answer.


best regards