{"id":207,"date":"2012-05-07T13:19:38","date_gmt":"2012-05-07T13:19:38","guid":{"rendered":"http:\/\/www.struck.de\/blog\/?p=207"},"modified":"2012-05-14T11:54:35","modified_gmt":"2012-05-14T11:54:35","slug":"suppressed-sampling-clock-sidebands-on-sis3302-digitizer","status":"publish","type":"post","link":"https:\/\/www.struck.de\/blog\/?p=207","title":{"rendered":"Suppressed sampling clock sidebands on SIS3302 digitizer"},"content":{"rendered":"

\u00a0A suppressed contribution from the 230 KHz switching regulators of the 1.2 V and 1.8 V power supply can be seen in the sampling clock spectrum of the SIS3302. Both external and internal clock\u00a0operation are affected.<\/p>\n

While\u00a0no effects are expected in typical detector readout applications,\u00a0phase sensitive applications -as they are typically part of accelerator controls- may be affected by the imperfection unless the below described modifications\u00a0on the SIS3302 are implemented.<\/p>\n

Following three modifications are needed for improved 1.2 V and 1.8 V power supply filtering on the SIS3302 card.<\/p>\n

    \n
  1. Replace choke L600B W\u00fcrth part number 744.560.25\/LF\u00a0 (2,2\u03bcH, Struck part number: 00149) with W\u00fcrth part number 744.77.020\/LF (100\u03bcH, Struck part number: 04517,\u00a0 RS Components part number 617-1596). The replacement choke can be soldered onto the existing pads, the housing touches adjacent parts though.<\/li>\n
  2. Replace \u00a0choke L500B W\u00fcrth part 744.560.25\/LF\u00a0 (2,2\u03bcH, Struck part number: 00149) with W\u00fcrth part 744.56.20\/LF (100\u03bcH, Struck part number: 04512,\u00a0 RS Components part number 396-3099 )<\/li>\n
  3. Change capacitor\u00a0C500A (1206 footprint) from 150pF to 33pF (RS Components part number 669-8527 e.g.)<\/li>\n<\/ol>\n

    SIS3302 boards with serial number 266 and higher ship with the changes implemented already.<\/p>\n

    Below you can see the clock spectra of a SIS3302 sampling at 50 MHz prior and after the modification.<\/p>\n

    \"SIS3302<\/a>

    SIS3302 clock spectrum prior to modification<\/p><\/div>\n

     <\/p>\n

     <\/p>\n

     <\/p>\n

     <\/p>\n

     <\/p>\n

     <\/p>\n

     <\/p>\n

    \"SIS3302<\/a>

    SIS3302 clock spectrum after modification<\/p><\/div>\n

    We would like to thank Lars Soby from CERN and his team members for bringing the power supply induced clock imperfection to our attention.<\/p>\n","protected":false},"excerpt":{"rendered":"

    \u00a0A suppressed contribution from the 230 KHz switching regulators of the 1.2 V and 1.8 V power supply can be seen in the sampling clock spectrum of the SIS3302. Both external and internal clock\u00a0operation are affected. While\u00a0no effects are expected … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-207","post","type-post","status-publish","format-standard","hentry","category-digitizer"],"_links":{"self":[{"href":"https:\/\/www.struck.de\/blog\/index.php?rest_route=\/wp\/v2\/posts\/207","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.struck.de\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.struck.de\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.struck.de\/blog\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.struck.de\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=207"}],"version-history":[{"count":35,"href":"https:\/\/www.struck.de\/blog\/index.php?rest_route=\/wp\/v2\/posts\/207\/revisions"}],"predecessor-version":[{"id":246,"href":"https:\/\/www.struck.de\/blog\/index.php?rest_route=\/wp\/v2\/posts\/207\/revisions\/246"}],"wp:attachment":[{"href":"https:\/\/www.struck.de\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=207"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.struck.de\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=207"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.struck.de\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=207"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}