Digital Number Conversion
Suppose you are doing an experiment in which a digital-to-analog (D to A) conversion is
required. That is, your computer generates and stores a triangle wave in digital numbers:
The purpose is to represent a real triangle wave:
We do this for all the usual reasons (one computer can generate this signal and others
efficiently, transmit them to other computers without loss, more or less immune to
broadband noise, etc.)
This problem concerns the “steps” in the digital signal, which are not usually wanted in
the analog signal.
a) Suppose the maximum output of your computer DA card is 5 V. Suppose further
that it is a 12-bit card. Compute the minimum step size in volts.
b) Suppose you want to generate a signal of  4 mV but with a minimum of
“steppiness”. How would you do that?
c) What binary number corresponds to 2.57 V on your card? (Assume -5 V 
000000000000.)