difference between analog and digital board designing?

[honey 77]

Anybody tell me what is the difference between analog and digital boards designing? In single board why separating analog circuit and digital circuit.

 

[mf1364]

Hi
the main different beetween the analog and digital circuit refer to voltage level of data signal. in the digital boards the lowest value is zero and the highest level is 5v (TTL standard) but in the analog circuit data value can have values between the zero or 5v but in frankly speaking I think there is no difference between analog and digital board designing

 

[GUMY]

There is a lot of difference. For analog circuits You have to consider small voltage drops on ground line, capacitive coupling, inductive coupling, noise, offset voltage, bias current,.. All of these contribute to error in analog circuity. Digital circuits are imune to parasitic efects to a certain level. In general analog circuits require more knowlege and experience to design than digital. Exeption are high frequency (above 100MHz) digital circuits which are in some cases even harder to design.

 

[dehati]

Analog board is more difficult than the Digital board.

 

[marce]

Do a search on this forum for analogue digital layout and on google. It is such a basic question, that I would reccomend some study into both analogue and digital layout practices and also how to combine the two on one board.
www.hottconsultants.com/pdf.../june2001pcd_mixedsignal.pdf
The text file contains numerous links to PCB design related stuff.