Do I understanding the ADC behavior wrong? ACQT too big
Posted: Thu Nov 26, 2015 8:38 am
In the table 21-1 of datasheet 39775c (PIC18F87J50) at page 307 recommends a TAD of Fosc/64 and TACQ of TAD*16 for 48MHz operation.
So if I'm correct that means a TACQ of 21.333µS
TosC = 1/48MHz= 0.02083µS
TAD = TosC * 64= 1.333µS
TACQ = TAD * 16 = 21.333µS
But according to the equation 21-3 at page 306 of the same datasheet the minimum TACQ is 2.45µS, so, as far I can understand that means that I can set a TACQ multiplier of 2*TAD.
Is my reasoning correct?
If the TACQ is too big I get less conversions per time unit but there's no other negative consequences, Right? _________________ Electric Blue
Ttelmah
Joined: 11 Mar 2010 Posts: 19381
Posted: Thu Nov 26, 2015 9:37 am
I don't see anywhere where it suggests TAD*16 for Tacq?.
E_Blue
Joined: 13 Apr 2011 Posts: 417
Posted: Thu Nov 26, 2015 11:09 am
You are right, my mistake I saw the ADCs2:0 column as ACQT2:0 _________________ Electric Blue
Ttelmah
Joined: 11 Mar 2010 Posts: 19381
Posted: Thu Nov 26, 2015 3:29 pm
I had a faint suspicion when I looked at the table.
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum