{"id":169,"date":"2008-09-02T11:34:41","date_gmt":"2008-09-02T16:34:41","guid":{"rendered":"http:\/\/www.circuitdesign.info\/2008\/09\/example-simulink-model-scripts\/"},"modified":"2008-11-19T06:12:16","modified_gmt":"2008-11-19T11:12:16","slug":"example-simulink-model-scripts","status":"publish","type":"post","link":"https:\/\/www.circuitdesign.info\/blog\/2008\/09\/example-simulink-model-scripts\/","title":{"rendered":"Example Simulink model &amp; scripts for continuous-time sigma-delta ADC"},"content":{"rendered":"<p>Response to EDABoard question: <a href=\"http:\/\/www.edaboard.com\/ftopic326495.html\">ADC in Matlab simulink<\/a><\/p>\n<p>I&#8217;ve put together a 2nd order continuous sigma-delta Simulink model as a starting point. This is the multi-port feedback configuration (feeds back into input of 1st and 2nd integrators). I tried a 1st-order sigma-delta, but it&#8217;s hard to demonstrate noise-shaping with a 1st order, since they are not chaotic enough. Even the 2nd order shows some limit cycles. The simulink model has these features:<\/p>\n<ul>\n<li>Parameters<br \/>\nF1 : gain of 1st integrator<br \/>\nF2: gain of 2nd integrator<br \/>\nA1\/A2 (optional): models finite circuit gain of integrators<br \/>\nfmod: frequency of input (sinusoid)<br \/>\nacmag: amplitude of input<br \/>\ntQ: sampling period of quantizer<br \/>\nncyc: number of cycles (of input) to analyze for FFT<br \/>\nkcyc: number of cycles (of input) to leave for startup<\/li>\n<li>single-bit quantizer<\/li>\n<li>multi-point feeeback (requires 2 DAC&#8217;s)<\/li>\n<\/ul>\n<p>I&#8217;ve also created a matlab file that runs this model and does an FFT on the output. This file runs the simulink model and plots an FFT of the output. I haven&#8217;t messed with the coefficients or anything, but it is a good starting point.<\/p>\n<p><a href=\"http:\/\/www.circuitdesign.info\/wp-content\/uploads\/2008\/09\/simulinkadcexample.tar\">SimulinkADCExample<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>I&#8217;ve put together a 2nd order continuous sigma-delta Simulink model as a starting point. This is the multi-port feedback configuration (feeds back into input of 1st and 2nd integrators).<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[3],"tags":[19,104,47,49,46,50,44,45],"class_list":["post-169","post","type-post","status-publish","format-standard","hentry","category-analog-pro","tag-adc","tag-continuous-time-sigma-delta","tag-example","tag-feedback","tag-matlab","tag-quantizer","tag-sigma-delta","tag-simulink"],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/poCEy-2J","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.circuitdesign.info\/blog\/wp-json\/wp\/v2\/posts\/169","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.circuitdesign.info\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.circuitdesign.info\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.circuitdesign.info\/blog\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.circuitdesign.info\/blog\/wp-json\/wp\/v2\/comments?post=169"}],"version-history":[{"count":13,"href":"https:\/\/www.circuitdesign.info\/blog\/wp-json\/wp\/v2\/posts\/169\/revisions"}],"predecessor-version":[{"id":420,"href":"https:\/\/www.circuitdesign.info\/blog\/wp-json\/wp\/v2\/posts\/169\/revisions\/420"}],"wp:attachment":[{"href":"https:\/\/www.circuitdesign.info\/blog\/wp-json\/wp\/v2\/media?parent=169"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.circuitdesign.info\/blog\/wp-json\/wp\/v2\/categories?post=169"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.circuitdesign.info\/blog\/wp-json\/wp\/v2\/tags?post=169"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}