Schreier Tool Set for Delta-Sigma Modulator Design (Dec. 1992)

These   programs   are   available   via   anonymous   ftp   from
next242.ece.orst.edu     (128.193.48.65).    Please    send    me
(schreier@ece.orst.edu) e-mail if you obtain a copy. That way,  I
can  keep  you posted regarding any updates and improvements that
are made.

To compile all the tools, type "make" in this directory. Compila-
tion  has only been verified on HP/Apollo machines. You will have
to change the Makefiles to suit your environment. The bin  direc-
tory  will then contain the executables which constitute the tool
set.

The examples directory contains an example design and  simulation
of  a  4th-order  delta-sigma  modulator. The ntf is synthesized,
simulated, mapped onto the cascade-of-resonators topology,  simu-
lated  again, scaled for dynamic range and resimulated once more.
Just modify your path to include the new programs and type "make"
and  watch  it  happen.   To do all the  simulations takes  about
one  hour.  Also included in this directory  are  NTF  files  for
common single-loop modulators.

The classes directory contains C++ classes  which  were  used  to
build  the  tools. You may find them useful if you intend to code
your own applications. The classes come with demo and help  files
(courtesy Giri Rangan at OSU (gnk@aldur.ece.orst.edu)).

KNOWN BUGS:

Documentation is scant. You get this  README  file,  the  example
directory, the  short PostScript  description  file  Notes.ps and
of course, the source code.

spectralAnalysis  does incorrect calculations for  f0=1 when used
with the -w option. Use another value for the test frequency.

realize  only  works  for  even-order  transfer  functions.    At
present, there is no work-around; you have to do the calculations
yourself.