Hi all,
First, let me thank everybody who replied on my request.
Probably, I should be more concrete.
I know the basics of D/A conversion, but I am absolute
novice in MCU designed devices.

I need the linear voltage source to control the high power
current source (120 A) which drives the superconducting magnet (9 T).
Well, the old source has 10 bit resolution, and the field steps are
not suitable for me. I think, 16 bit will be ok and let me fine tuning.
About the scales:
 voltage output - -5...0...+5V (and this is ok with MAX542 + MAX495)
 one step duration - >5 msec. (the whole range - not faster then 500 sec)
I just don't know will , for instance, pic16c84 be enough for my purpose?
I need to be able to change both Vend and Tstep from some small keyboard
(and also computer), see the settled values on the LED/LCD 6 digit display,
have some protection (low limit for Tstep, upper - for Vend),
START/STOP control.
I have an idea how to make all of these by means of logic IC's, but may it
be more powerful and simple to use some cheap PIC MCU ?
If somebody has any ideas (experience) in that?
Useful links can also help me.

--
---------------------------------------------------------
|   Roman Dremov                      Na Slovance 2     |
|   Institute of Physics              180 40 Prague 8   |
|   Academy of Sciences               Czech Republic    |
|      phone:  +4202-21912736    fax: +4202-21912567    |
|       home:  +4202-8551040     (extension 794)        |
|     e-mail:   dremov@fzu.cz    ICQ: 13114621          |
|        WWW:   http://www.fzu.cz/~dremov               |
---------------------------------------------------------