{"id":4525,"date":"2024-05-07T02:21:27","date_gmt":"2024-05-07T02:21:27","guid":{"rendered":"https:\/\/beamq.com\/laser\/?p=4525"},"modified":"2024-05-07T02:21:27","modified_gmt":"2024-05-07T02:21:27","slug":"pin-photodiodes-3-db-bandwidth","status":"publish","type":"post","link":"https:\/\/beamq.com\/laser\/pin-photodiodes-3-db-bandwidth\/","title":{"rendered":"PIN photodiode&#8217;s 3 dB bandwidth"},"content":{"rendered":"\n<p>Characterize a PIN photodiode&#8217;s 3 dB bandwidth. The photodiode input is a laser source that is being modulated by an ESA RF output that performs a frequency sweep from 0-1.5 GHz. The output of the photodiode is then connect to a 50 \u03a9 resistor which is connected to ground. The ESA input terminals are connected over the 50 \u03a9 resistor. I have two pertinent questions:<\/p>\n\n\n\n<p>The spec sheet gives a 3 dB BW of 0.7 GHz. Can a regular breadboard be used for the circuit? Currently, I have the legs of the components connected together and the components themselves in air, since I read that the parasitics of the breadboard will interfere with the measurements. I did attempt to measure it with the breadboard and didn&#8217;t notice a large increase in noise.<br>I&#8217;m using a 50 \u03a9 resister since the input of the ESA is also 50 \u03a9. However, I&#8217;m still getting RF reflections in the output spectrum. I&#8217;m unfamiliar with RF circuits and measurement. How would I go about matching the impedance in a better manner?<\/p>\n\n\n\n<p><\/p>\n\n\n\n<figure class=\"wp-block-gallery columns-3 is-cropped\"><ul class=\"blocks-gallery-grid\"><li class=\"blocks-gallery-item\"><figure><img loading=\"lazy\" width=\"800\" height=\"507\" src=\"https:\/\/beamq.com\/laser\/wp-content\/uploads\/2024\/05\/HP-L1500A.png\" alt=\"\" data-id=\"4526\" data-link=\"https:\/\/beamq.com\/laser\/?attachment_id=4526\" class=\"wp-image-4526\"\/><\/figure><\/li><li class=\"blocks-gallery-item\"><figure><img loading=\"lazy\" width=\"800\" height=\"509\" src=\"https:\/\/beamq.com\/laser\/wp-content\/uploads\/2024\/05\/PIN-photodiodes-3-dB-bandwidth-1.png\" alt=\"\" data-id=\"4527\" data-link=\"https:\/\/beamq.com\/laser\/?attachment_id=4527\" class=\"wp-image-4527\"\/><\/figure><\/li><li class=\"blocks-gallery-item\"><figure><img loading=\"lazy\" width=\"800\" height=\"645\" src=\"https:\/\/beamq.com\/laser\/wp-content\/uploads\/2024\/05\/PIN-photodiodes-3-dB-bandwidth-2.png\" alt=\"\" data-id=\"4528\" data-link=\"https:\/\/beamq.com\/laser\/?attachment_id=4528\" class=\"wp-image-4528\"\/><\/figure><\/li><\/ul><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Characterize a PIN photodiode&#8217;s 3 dB bandwidth. The photodiode input is a laser source that is being modulated by an ESA RF output that performs a frequency sweep from 0-1.5 GHz. The output of the photodiode is then connect to a 50 \u03a9 resistor which is connected to ground. The ESA input terminals are connected [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"_links":{"self":[{"href":"https:\/\/beamq.com\/laser\/wp-json\/wp\/v2\/posts\/4525"}],"collection":[{"href":"https:\/\/beamq.com\/laser\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/beamq.com\/laser\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/beamq.com\/laser\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/beamq.com\/laser\/wp-json\/wp\/v2\/comments?post=4525"}],"version-history":[{"count":1,"href":"https:\/\/beamq.com\/laser\/wp-json\/wp\/v2\/posts\/4525\/revisions"}],"predecessor-version":[{"id":4529,"href":"https:\/\/beamq.com\/laser\/wp-json\/wp\/v2\/posts\/4525\/revisions\/4529"}],"wp:attachment":[{"href":"https:\/\/beamq.com\/laser\/wp-json\/wp\/v2\/media?parent=4525"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/beamq.com\/laser\/wp-json\/wp\/v2\/categories?post=4525"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/beamq.com\/laser\/wp-json\/wp\/v2\/tags?post=4525"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}