# $Header: README,v 1.6 97/02/27 12:59:22 space Exp $

Demonstration of an attenuator circuit in the bipolar DIMES-01 process.

After extraction, the circuit can be simulated using PSPICE.

See also, 
  "Low-voltage Low-power Controlled Attenuator for Hearing Aids"
  A. van Staveren and A.H.M. van Roermund, Electronic Letters,
  22nd. July 1993, Vol. 29, No. 15, pp. 1355-1356.

STEPS
=====

1.  Make project, use dimes01 technology and lambda = 0.1 (micron)
    % mkpr -p dimes01 -l 0.1 projectname

Rest assumes that you and your files are in the project directory.

2.  Use cgi to put attenuator layout into the database.
    % cgi attenua.gds

3.  Perform a flat extraction of cell attenua.
    % space -vF attenua

4.  Inspect circuit.
    % xspice -a attenua

Try out the options -c, -C, -r and -z for capacitance and resistance 
extraction.  

If you have PSPICE, you can perform a circuit simulation (after 
customizing the script nspice) as follows:

5.  % nspice attenua attenua.cmd


You can compare the extracted circuit against a reference circuit
using match.

6.  First add device descriptions for the bipolar transistors to the 
    database so that the reference circuit can be stored into the database
    using cspice
    % putdevmod pnpWP.dev npnBW.dev
    % cspice att_ref.spc

7.  Extract cell attenua, possibly after an error has been added to the 
    layout.
    % space -vF attenua

8.  Compare the extracted circuit against the reference circuit.
    % match -bindings att_ref attenua 

