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: 19546
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: 19546
Posted: Thu Nov 26, 2015 3:29 pm
I had a faint suspicion when I looked at the table.
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