{"id":1163,"date":"2013-12-01T15:22:31","date_gmt":"2013-12-01T14:22:31","guid":{"rendered":"http:\/\/www.sciencetronics.com\/greenphotons\/?p=1163"},"modified":"2025-06-16T18:38:13","modified_gmt":"2025-06-16T16:38:13","slug":"mosfets-what-the-datasheet-doesnt-tell-you","status":"publish","type":"post","link":"https:\/\/www.sciencetronics.com\/greenphotons\/?p=1163","title":{"rendered":"MOSFETs &#8211; what the datasheet doesn&#8217;t tell you"},"content":{"rendered":"<p><strong>I am planning<\/strong> to construct a logarithmic current meter and were yesterday doing some simulations with <a href=\"http:\/\/www.linear.com\/designtools\/software\/\" target=\"_blank\">LTspice<\/a>. Using a logarithmic converter you can span a wide range of currents with a single readout without the necessity to switch ranges. Of course this has disadvantages as well, but if you know what you are doing it is well worth the effort.<\/p>\n<p><strong>Essentially <\/strong>you have three options<\/p>\n<ul>\n<li>using an integrated logarithmic amplifier or converter<\/li>\n<li>using a bipolar transistor<\/li>\n<li>using a field-effect transistor in deep sub-threshold<\/li>\n<\/ul>\n<p><strong>You will<\/strong> find plenty of ideas on the internet for the conversion &#8211; but most for those are aimed at quite low currents. My project would require a current range of up to 200 mA which exceeds the capability of all integrated logarithmic amplifiers I found so far, at the same time I can sacrifice some accuracy in the low ranges.<\/p>\n<p><strong>After a while<\/strong> I came across the idea to utilize the sub-threshold of a MOSFET. In this region the drain current depends exponentially on the gate-source voltage, not quadratic as for higher currents. Entering a corresponding test circuit into the LTspice simulator nothing happened, as I suspected and then found out as well, sub-threshold behavior is in general not reliably implemented in the device models! <\/p>\n<p><strong>Looking<\/strong> into a datasheet of a power MOSFET you well find out that the behavior in this region is also not considered worth while printing. So all you can do is to measure it yourself.<\/p>\n<figure id=\"attachment_1155\" aria-describedby=\"caption-attachment-1155\" style=\"width: 300px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131130_FET_char.png\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131130_FET_char-300x153.png\" alt=\"Measurement circuit for the electrical characteristics of a MOSFET.\" width=\"300\" height=\"153\" class=\"size-medium wp-image-1155\" srcset=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131130_FET_char-300x153.png 300w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131130_FET_char-150x76.png 150w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131130_FET_char-400x204.png 400w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131130_FET_char.png 533w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-1155\" class=\"wp-caption-text\">Measurement circuit for the electrical characteristics of a MOSFET.<\/figcaption><\/figure>\n<p><strong>I quickly wired<\/strong> up a BUZ11 (manufacturer ST, date code A709, Malaysia) to my lab supply with a variable gate voltage and a fixed drain voltage of +5V, one multimeter as an amperemeter  between the drain and the power supply and here is the result:<\/p>\n<figure id=\"attachment_1154\" aria-describedby=\"caption-attachment-1154\" style=\"width: 169px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131130_BUZ11_subthres.png\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131130_BUZ11_subthres-169x300.png\" alt=\"Sub-threshold behavior of a BUZ11 enhancement power MOSFET for VDS=5V\" width=\"169\" height=\"300\" class=\"size-medium wp-image-1154\" srcset=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131130_BUZ11_subthres-169x300.png 169w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131130_BUZ11_subthres-579x1024.png 579w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131130_BUZ11_subthres-84x150.png 84w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131130_BUZ11_subthres.png 686w\" sizes=\"auto, (max-width: 169px) 100vw, 169px\" \/><\/a><figcaption id=\"caption-attachment-1154\" class=\"wp-caption-text\">Sub-threshold behavior of a BUZ11 enhancement power MOSFET for VDS=5V.<\/figcaption><\/figure>\n<p><strong>As you can see<\/strong> the drain current <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-8215b3fd40e5ff7e0a1dd68e3a7cf0ec_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#73;&#95;&#68;\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"15\" style=\"vertical-align: -2px;\"\/> shows at least 4.5 decades of exponential behavior below the threshold voltage of  <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-52824457d2517cc82c3e9b40b013b383_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#86;&#95;&#123;&#71;&#83;&#125;&#61;&#83;&#73;&#123;&#51;&#46;&#48;&#125;&#123;&#118;&#111;&#108;&#116;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"105\" style=\"vertical-align: -2px;\"\/>, which by the way corresponds quite exactly to the typical threshold voltage according to the datasheet.<\/p>\n<p><strong>Fitting the data<\/strong> I was able to extract the behavior of exactly this transistor at <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-9cb45fb0deedf37538e9659c5e6bb7d6_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#86;&#95;&#123;&#68;&#83;&#125;&#61;&#83;&#73;&#123;&#53;&#125;&#123;&#118;&#111;&#108;&#116;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"94\" style=\"vertical-align: -2px;\"\/> as<\/p>\n<p>[I_D  = K left(1-frac{V_{GS}}{V_T} right)^2 ]<\/p>\n<p>with <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-411628467cb4118b8b3460f19a011fb3_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#75;&#61;&#83;&#73;&#123;&#52;&#46;&#54;&#53;&#125;&#123;&#97;&#109;&#112;&#101;&#114;&#101;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"124\" style=\"vertical-align: -3px;\"\/> and <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-506baffa753b39763209bfb8edcaaa8a_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#86;&#95;&#84;&#61;&#83;&#73;&#123;&#51;&#46;&#48;&#52;&#125;&#123;&#118;&#111;&#108;&#116;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"104\" style=\"vertical-align: -2px;\"\/> for <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-f3ed49bfd4989699e99c5eed404d97a6_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#86;&#95;&#123;&#71;&#83;&#125;&#62;&#86;&#95;&#84;\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"61\" style=\"vertical-align: -2px;\"\/> and<\/p>\n<p>[I_D = I_0,e^{sfrac{q,V_{GS}}{n,kT}}}]<\/p>\n<p>with <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-719f2ae45210fbad96e948acd463ec83_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#115;&#102;&#114;&#97;&#99;&#123;&#107;&#84;&#125;&#123;&#113;&#125;&#61;&#83;&#73;&#123;&#50;&#54;&#125;&#123;&#109;&#105;&#108;&#108;&#105;&#118;&#111;&#108;&#116;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"14\" width=\"170\" style=\"vertical-align: -3px;\"\/>, <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-c6fa1ebb80bab6ae3912d0c480701ab1_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#110;&#61;&#51;&#46;&#51;&#54;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"53\" style=\"vertical-align: 0px;\"\/> and <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-e8877956c0938c34bccaa1bdca40ab14_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#73;&#95;&#48;&#61;&#83;&#73;&#123;&#50;&#46;&#53;&#56;&#101;&#45;&#49;&#56;&#125;&#123;&#97;&#109;&#112;&#101;&#114;&#101;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"163\" style=\"vertical-align: -3px;\"\/>.<\/p>\n<p><strong>For any practical use<\/strong> be aware of that the sub-threshold behavior is most likely to vary widely between different specimens and that this behavior also is extremely sensitive to temperature variations.<\/p>\n<figure id=\"attachment_1177\" aria-describedby=\"caption-attachment-1177\" style=\"width: 169px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131201_IRFZ24_subthres.png\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131201_IRFZ24_subthres-169x300.png\" alt=\"Sub-threshold behavior of a IRFZ24 enhancement power MOSFET.\" width=\"169\" height=\"300\" class=\"size-medium wp-image-1177\" srcset=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131201_IRFZ24_subthres-169x300.png 169w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131201_IRFZ24_subthres-579x1024.png 579w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131201_IRFZ24_subthres-84x150.png 84w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131201_IRFZ24_subthres.png 686w\" sizes=\"auto, (max-width: 169px) 100vw, 169px\" \/><\/a><figcaption id=\"caption-attachment-1177\" class=\"wp-caption-text\">Sub-threshold behavior of a IRFZ24 enhancement power MOSFET.<\/figcaption><\/figure>\n<p>An <strong>IRFZ24<\/strong> (manufacturer IR, date code 8842) at <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-9cb45fb0deedf37538e9659c5e6bb7d6_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#86;&#95;&#123;&#68;&#83;&#125;&#61;&#83;&#73;&#123;&#53;&#125;&#123;&#118;&#111;&#108;&#116;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"94\" style=\"vertical-align: -2px;\"\/> gives<\/p>\n<p>[I_D  = K left(1-frac{V_{GS}}{V_T} right)^2 ]<\/p>\n<p>with <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-a1216b392846e3aa6044ad5037d0effd_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#75;&#61;&#83;&#73;&#123;&#51;&#46;&#56;&#52;&#125;&#123;&#97;&#109;&#112;&#101;&#114;&#101;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"124\" style=\"vertical-align: -3px;\"\/> and <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-10023256e8ed00cd51a1012adc679ca3_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#86;&#95;&#84;&#61;&#83;&#73;&#123;&#51;&#46;&#49;&#53;&#125;&#123;&#118;&#111;&#108;&#116;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"104\" style=\"vertical-align: -2px;\"\/> for <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-f3ed49bfd4989699e99c5eed404d97a6_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#86;&#95;&#123;&#71;&#83;&#125;&#62;&#86;&#95;&#84;\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"61\" style=\"vertical-align: -2px;\"\/> and<\/p>\n<p>[I_D = I_0,e^{sfrac{q,V_{GS}}{n,kT}}}]<\/p>\n<p>with <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-719f2ae45210fbad96e948acd463ec83_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#115;&#102;&#114;&#97;&#99;&#123;&#107;&#84;&#125;&#123;&#113;&#125;&#61;&#83;&#73;&#123;&#50;&#54;&#125;&#123;&#109;&#105;&#108;&#108;&#105;&#118;&#111;&#108;&#116;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"14\" width=\"170\" style=\"vertical-align: -3px;\"\/>, <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-17aedb5a63238c67604524e029174106_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#110;&#61;&#52;&#46;&#49;&#57;\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"53\" style=\"vertical-align: -1px;\"\/> and <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-e802f6768bbf473524e9286826c5f77d_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#73;&#95;&#48;&#61;&#83;&#73;&#123;&#49;&#46;&#50;&#51;&#101;&#45;&#49;&#53;&#125;&#123;&#97;&#109;&#112;&#101;&#114;&#101;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"163\" style=\"vertical-align: -3px;\"\/>.<\/p>\n<figure id=\"attachment_1178\" aria-describedby=\"caption-attachment-1178\" style=\"width: 169px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131201_IRFZ46_subthres.png\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131201_IRFZ46_subthres-169x300.png\" alt=\"Sub-threshold behavior of a IRFZ46 enhancement power MOSFET.\" width=\"169\" height=\"300\" class=\"size-medium wp-image-1178\" srcset=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131201_IRFZ46_subthres-169x300.png 169w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131201_IRFZ46_subthres-579x1024.png 579w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131201_IRFZ46_subthres-84x150.png 84w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131201_IRFZ46_subthres.png 686w\" sizes=\"auto, (max-width: 169px) 100vw, 169px\" \/><\/a><figcaption id=\"caption-attachment-1178\" class=\"wp-caption-text\">Sub-threshold behavior of a IRFZ46 enhancement power MOSFET.<\/figcaption><\/figure>\n<p>An <strong>IRFZ46<\/strong> (manufacturer IR, date code 944D) at <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-9cb45fb0deedf37538e9659c5e6bb7d6_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#86;&#95;&#123;&#68;&#83;&#125;&#61;&#83;&#73;&#123;&#53;&#125;&#123;&#118;&#111;&#108;&#116;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"94\" style=\"vertical-align: -2px;\"\/> gives<\/p>\n<p>[I_D  = K left(1-frac{V_{GS}}{V_T} right)^2 ]<\/p>\n<p>with <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-3392a0f875580b4918dc9c95a186d9a4_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#75;&#61;&#83;&#73;&#123;&#49;&#48;&#46;&#50;&#125;&#123;&#97;&#109;&#112;&#101;&#114;&#101;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"124\" style=\"vertical-align: -3px;\"\/> and <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-1b7ff86da3fe118f092ccdb7bcb9c602_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#86;&#95;&#84;&#61;&#83;&#73;&#123;&#51;&#46;&#50;&#54;&#125;&#123;&#118;&#111;&#108;&#116;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"104\" style=\"vertical-align: -2px;\"\/> for <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-f3ed49bfd4989699e99c5eed404d97a6_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#86;&#95;&#123;&#71;&#83;&#125;&#62;&#86;&#95;&#84;\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"61\" style=\"vertical-align: -2px;\"\/> and<\/p>\n<p>[I_D = I_0,e^{sfrac{q,V_{GS}}{n,kT}}}]<\/p>\n<p>with <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-719f2ae45210fbad96e948acd463ec83_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#115;&#102;&#114;&#97;&#99;&#123;&#107;&#84;&#125;&#123;&#113;&#125;&#61;&#83;&#73;&#123;&#50;&#54;&#125;&#123;&#109;&#105;&#108;&#108;&#105;&#118;&#111;&#108;&#116;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"14\" width=\"170\" style=\"vertical-align: -3px;\"\/>, <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-11ba7a4ec010e811516df8090ba4615b_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#110;&#61;&#51;&#46;&#53;&#48;\" title=\"Rendered by QuickLaTeX.com\" height=\"11\" width=\"53\" style=\"vertical-align: 0px;\"\/> and <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/ql-cache\/quicklatex.com-aa840cc017f555e9b49e3cce5e1ee8e2_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#73;&#95;&#48;&#61;&#83;&#73;&#123;&#49;&#46;&#55;&#51;&#101;&#45;&#49;&#56;&#125;&#123;&#97;&#109;&#112;&#101;&#114;&#101;&#125;\" title=\"Rendered by QuickLaTeX.com\" height=\"14\" width=\"163\" style=\"vertical-align: -3px;\"\/>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>I am planning to construct a logarithmic current meter and were yesterday doing some simulations with LTspice. Using a logarithmic converter you can span a wide range of currents with a single readout without the necessity to switch ranges. Of course this has disadvantages as well, but if you know what you are doing it [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":1155,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"enabled":false},"version":2}},"categories":[11,8,27],"tags":[],"class_list":["post-1163","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-electronics_en","category-everything_en","category-science_en","entry","has-media"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2013\/12\/20131130_FET_char.png","jetpack_shortlink":"https:\/\/wp.me\/p48grL-iL","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/posts\/1163","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1163"}],"version-history":[{"count":16,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/posts\/1163\/revisions"}],"predecessor-version":[{"id":2457,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/posts\/1163\/revisions\/2457"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/media\/1155"}],"wp:attachment":[{"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1163"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1163"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1163"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}