[sci.electronics] Needed: 4 bit D/A IC, low sample rate

smiller@wet.UUCP (Gregory Shane Miller) (03/15/91)

14 Wednesday March 1991

I'm looking for a simple 4 bit D/A IC.  I have a 24 bit digital I/O card
of which 4 (output) lines would be connected to the 4 bit D/A IC.  Each
line is driven with standard TTL values.  I want to feed the analog output
into the speed control unit for a varible 40K RPM brushless DC spindle motor.
Since I'm controlling a spindle motor, high "sampling" rates are not needed.

I'm hoping that when the 4 output lines are:

              4 3 2 1 <- Line number
              | | | |
Line value -> 0 0 0 0 -> the spindle motor is OFF
0 -> 0V       0 0 0 1 -> the spindle motor runs at 2.6K RPM
1 -> +5V      0 0 1 0 -> the spindle motor runs at 5.2K RPM
              0 0 1 1 -> the spindle motor runs at 7.8K RPM
                 .
                 .
                 .
              1 1 1 1 -> the spindle motor runs at 40K RPM

Does such an IC exist?  I need commerical quanities.  I can be reached at
smiller@wet.UUCP.  Thankyou very much.
-- 
--
G. Shane Miller [ smiller@wet.UUCP ]  out!