{"id":848,"date":"2012-11-11T19:36:42","date_gmt":"2012-11-11T18:36:42","guid":{"rendered":"http:\/\/www.sciencetronics.com\/greenphotons\/?p=848"},"modified":"2025-06-16T18:38:19","modified_gmt":"2025-06-16T16:38:19","slug":"the-best-led-bulb-part-2","status":"publish","type":"post","link":"https:\/\/www.sciencetronics.com\/greenphotons\/?p=848","title":{"rendered":"The best LED bulb? &#8211; part 2"},"content":{"rendered":"<p>Ok, let us continue the reverse engineering of the E27 LED bulb <em>LEDARE<\/em> from <a href=\"http:\/\/www.ikea.com\/se\/sv\/catalog\/products\/10222473\/\" target=\"_blank\">IKEA<\/a>. After describing the actual light emitting diode assembly in the <a href=\"http:\/\/www.sciencetronics.com\/greenphotons\/?p=828\" title=\"The best LED bulb?\">previous post<\/a>, I will today look deeper under the hood into the power supply.<\/p>\n<figure id=\"attachment_849\" aria-describedby=\"caption-attachment-849\" style=\"width: 300px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8046A_1000.jpg\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8046A_1000-300x163.jpg\" alt=\"\" title=\"_IGP8046A_1000\" width=\"300\" height=\"163\" class=\"size-medium wp-image-849\" srcset=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8046A_1000-300x163.jpg 300w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8046A_1000-150x81.jpg 150w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8046A_1000-400x217.jpg 400w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8046A_1000.jpg 990w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-849\" class=\"wp-caption-text\">Disassembling the socket of the clear E27 LED bulb LEDARE from IKEA to reveal the power supply.<\/figcaption><\/figure>\n<p>The power supply itself is located in a plastic cylinder which is screwed to the cast metal housing of the lamp. It is the most elaborate design I have seen so far in any LED or CFL-light. The circuit contains three inductors in the line filter and PFC (power factor correction), two bridge rectifiers, two transformers and only one electrolytic capacitor. Since electrolytic capacitors are the most vulnerable components in these circuits this promises some longevity for the lamp.<\/p>\n<figure id=\"attachment_850\" aria-describedby=\"caption-attachment-850\" style=\"width: 300px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8047A_1000.jpg\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8047A_1000-300x98.jpg\" alt=\"\" title=\"_IGP8047A_1000\" width=\"300\" height=\"98\" class=\"size-medium wp-image-850\" srcset=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8047A_1000-300x98.jpg 300w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8047A_1000-150x49.jpg 150w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8047A_1000-400x131.jpg 400w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8047A_1000.jpg 975w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-850\" class=\"wp-caption-text\">Top-side view of the power supply.<\/figcaption><\/figure>\n<p>The heart of the design can be seen on the bottom side of the circuit board. It is an <a href=\"http:\/\/www.ti.com\/product\/tps92070\" target=\"_blank\">TPS92070 High-Efficiency Integrated Dimming LED Lighting Driver Controller <\/a> from Texas Instruments. Even though the LED light bulb itself is marked as <em>not-dimmable<\/em>, the controller chip itself supports dimming.<\/p>\n<p><figure id=\"attachment_851\" aria-describedby=\"caption-attachment-851\" style=\"width: 300px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8050a_1000.jpg\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8050a_1000-300x112.jpg\" alt=\"\" title=\"_IGP8050a_1000\" width=\"300\" height=\"112\" class=\"size-medium wp-image-851\" srcset=\"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8050a_1000-300x112.jpg 300w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8050a_1000-150x56.jpg 150w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8050a_1000-400x150.jpg 400w, https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8050a_1000.jpg 930w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-851\" class=\"wp-caption-text\">Bottom-side of the circuit board with the power supply of the LED light bulb LEDARE from IKEA. Central part is the TPS92070 from Texas Instruments.<\/figcaption><\/figure> <!--more--><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Ok, let us continue the reverse engineering of the E27 LED bulb LEDARE from IKEA. After describing the actual light emitting diode assembly in the previous post, I will today look deeper under the hood into the power supply. The power supply itself is located in a plastic cylinder which is screwed to the cast [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":850,"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":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"enabled":false},"version":2}},"categories":[11,8,40],"tags":[],"class_list":["post-848","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-electronics_en","category-everything_en","category-leds","entry","has-media"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/11\/IGP8047A_1000.jpg","jetpack_shortlink":"https:\/\/wp.me\/p48grL-dG","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/posts\/848","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=848"}],"version-history":[{"count":5,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/posts\/848\/revisions"}],"predecessor-version":[{"id":2489,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/posts\/848\/revisions\/2489"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/media\/850"}],"wp:attachment":[{"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=848"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=848"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=848"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}