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Presents application use cases such as particle size analyzers, barcode readers, UV sensing, rotary encoders, and color sensing, supported by device lineup overview and package options.",{"@graph":14,"@context":72},[15,34,55],{"@type":16,"itemListElement":17},"BreadcrumbList",[18,23,27,31],{"item":19,"name":20,"@type":21,"position":22},"https://docshare.wps.com","Home","ListItem",1,{"item":24,"name":25,"@type":21,"position":26},"https://docshare.wps.com/document/","Document",2,{"item":28,"name":29,"@type":21,"position":30},"https://docshare.wps.com/document/technology/","Technology",3,{"item":32,"name":10,"@type":21,"position":33},"https://docshare.wps.com/document/si-photodiodes-technical-note/670037/",4,{"url":32,"name":10,"@type":35,"image":36,"author":41,"headline":10,"publisher":44,"fileFormat":47,"inLanguage":8,"description":12,"dateModified":48,"datePublished":49,"encodingFormat":47,"isAccessibleForFree":50,"interactionStatistic":51},"DigitalDocument",{"url":37,"@type":38,"width":39,"height":40},"https://docshare.wps.com/thumbnails/si-photodiodes-technical-note/670037.png","ImageObject",300,407,{"name":42,"@type":43},"Stanford","Person",{"url":19,"name":45,"@type":46},"DocShare","Organization","application/pdf","2026-11-02","2026-11-01",true,{"@type":52,"interactionType":53,"userInteractionCount":22},"InteractionCounter",{"@type":54},"ViewAction",{"@type":56,"mainEntity":57},"FAQPage",[58,64,68],{"name":59,"@type":60,"acceptedAnswer":61},"What happens in a Si photodiode when illuminated by light?","Question",{"text":62,"@type":63},"When incident light has energy greater than the band gap energy, it creates electron-hole pairs in the P-layer, depletion layer, and N-layer. The electric field in the depletion layer drives electrons toward the N-layer and holes toward the P-layer, producing a measurable current when electrodes are connected to an external circuit.","Answer",{"name":65,"@type":60,"acceptedAnswer":66},"Which characteristics are covered for evaluating Si photodiode performance?",{"text":67,"@type":63},"The document covers current vs. voltage characteristics, linearity, spectral response, noise characteristics, sensitivity uniformity, and response speed. These are used to judge how the device responds to light level and frequency content.",{"name":69,"@type":60,"acceptedAnswer":70},"How can Si photodiodes be used with an op amp?",{"text":71,"@type":63},"The note provides guidance for connecting the photodiode to an op amp and includes application circuit examples. These circuits support signal amplification and practical measurement in different systems.","https://schema.org",{"og:url":32,"og:type":74,"og:title":10,"og:site_name":45,"og:description":12},"article",{"robots":76,"canonical":32},"index,follow",{"doc_id":78,"site_id":7},670037,1793566145,{"code":4,"msg":81,"data":82},"success",[83,87,91,95,100,104,109,114,119,122,126],{"id":22,"doc_module":4,"doc_module_name":25,"category_name":84,"show_sort_weight":85,"slug":86},"Story & Novel",90,"story-novel",{"id":26,"doc_module":4,"doc_module_name":25,"category_name":88,"show_sort_weight":89,"slug":90},"Literature",80,"literature",{"id":33,"doc_module":4,"doc_module_name":25,"category_name":92,"show_sort_weight":93,"slug":94},"Exam",70,"exam",{"id":96,"doc_module":4,"doc_module_name":25,"category_name":97,"show_sort_weight":98,"slug":99},5,"Comic",60,"comic",{"id":101,"doc_module":4,"doc_module_name":25,"category_name":29,"show_sort_weight":102,"slug":103},6,50,"technology",{"id":105,"doc_module":4,"doc_module_name":25,"category_name":106,"show_sort_weight":107,"slug":108},7,"Healthcare",40,"healthcare",{"id":110,"doc_module":4,"doc_module_name":25,"category_name":111,"show_sort_weight":112,"slug":113},8,"Research & Report",30,"research-report",{"id":115,"doc_module":4,"doc_module_name":25,"category_name":116,"show_sort_weight":117,"slug":118},9,"Religion & Spirituality",20,"religion-spirituality",{"id":117,"doc_module":4,"doc_module_name":25,"category_name":120,"show_sort_weight":117,"slug":121},"World Cup","world-cup",{"id":123,"doc_module":4,"doc_module_name":25,"category_name":124,"show_sort_weight":123,"slug":125},10,"Lifestyle","lifestyle",{"id":127,"doc_module":4,"doc_module_name":25,"category_name":128,"show_sort_weight":96,"slug":129},19,"General","general",{"code":4,"msg":81,"data":131},{"doc_id":78,"user_id":132,"nickname":42,"user_avatar":133,"doc_module":4,"category_id":101,"category_name":29,"doc_title":10,"doc_description":12,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":22,"is_deleted":4,"is_public":22,"is_downloadable":22,"audit_status":22,"page_count":139,"language":140,"language_code":8,"site_id":7,"html_lang":8,"table_of_contents":141,"faqs":142,"seo_title":143,"seo_description":12,"update_tm":79,"read_time":144},2336477552062,"https://ap-avatar.wpscdn.com/davatar_994ba38a5ba835b3df7d355c54d3ed8d","Si photodiodes  \nTechnical note  \nContents  \n1.  \nP.02  \n2.  \nP.03  \nOperating principle 1-1 Structure  \n1-2 Equivalent circuit  \nCharacteristics  \n2-1 Current vs. voltage characteristics 2-2 Linearity  \n2-3 Spectral response  \n2-4 Noise characteristics 2-5 Sensitivity uniformity  \n2-6 Response speed  \n3.  \nP.09  \n4.  \nP.16  \nHow to use  \n3-1 Connection to an op amp 3-2 Application circuit examples  \nApplications  \n4-1 Particle size analyzers (laser diffraction and scattering method)  \n4-2 Barcode readers  \n4-3 UV sensors  \n4-4 Rotary encoders  \n4-5 Color sensors  \nPhotodiodes are photosensors that generate a current or voltage when the PN junction in the semiconductor is irradiated by light. The term photodiode can be broadly defined to include even solar batteries, but it usually means sensors that accurately detect changes in light level. Si photodiodes provide the following features and are widely used to detect the presence or absence, intensity, and color of light, etc.  \n Excellent linearity with respect to incident light  Mechanically rugged  Low noise  \n Compact and lightweight  Wide spectral response range  Long life  \nThe lineup of Si photodiodes we manufacture utilizing our own advanced semiconductor process technologies covers a broad spectral range from the near infrared to ultraviolet and even to high-energy regions, and features highspeed response, high sensitivity, and low noise. Hamamatsu Si photodiodes are used in a wide range of applications including medical and analytical fields, scientific measurements, optical communications, and general electronic products. These photodiodes are available in various packages such as metal, ceramic, and plastic packages, as well as in surface mount types. Hamamatsu also offers custom-designed devices to meet special needs.  \n Hamamatsu Si photodiodes  \n\n| Type | Features | Product examples |\n| --- | --- | --- |\n| Si photodiode | These photodiodes feature high sensitivity and low noise, and they are specifically designed for precision photometry and general photometry in the visible range. | •For UV to near infrared range\u003Cbr>•For visible to near infrared range •For visible range\u003Cbr>•RGB color sensor\u003Cbr>•For vacuum ultraviolet (VUV) detection •For monochromatic light detection •For electron beam detection |\n| Si PIN photodiode | Si PIN photodiodes deliver high-speed response when operated with a reverse voltage applied and are suitable for use in optical fiber communications, optical disk pickups, etc. | •Cutoff frequency: 10 MHz or more |\n| IR-enhanced\u003Cbr>Si PIN photodiode | These photodiodes have improved sensitivity in the near infrared region above 900 nm . | •For YAG laser monitoring |\n| Multi-element\u003Cbr>Si photodiode | Si photodiode arrays consist of multiple elements formed in a linear or two-dimensional arrangement in a single package. These photodiode arrays are used in a wide range of applications such as light position detection and spectrophotometry. | •Segmented photodiode\u003Cbr>•One-dimensional photodiode array |\n| Si photodiode with preamp, thermoelectrically cooled Si photodiode | Si photodiodes with preamp incorporate a photodiode and a preamplifier into the same package, so they are highly immune to external noise and allow compact circuit design. Thermoelectrically cooled types offer drastically improved S/N. | •For analysis and measurement |\n\n01  \n1-1 Structure  \nFigure 1-1 shows a cross section example of a Si photodiode. The P-type region (P-layer) at the photosensitive surface and the N-type region (N-layer) at the substrate form a PN junction which operates as a photoelectric converter. The usual P-layer for a Si photodiode is formed by selective diffusion of boron to a thickness of approx. 1 μm or less, and the intrinsic region at the junction between the P-layer and N-layer is known as the depletion layer. By controlling the thickness of the outer P-layer, N-layer, and bottom N+-layer as well as the dopant concentration, the spectral response and fr","cbCaiacmEqeW2ASF","https://ap.wps.com/l/cbCaiacmEqeW2ASF","pdf",2970195,17,"English","# Operating principle\n## Structure\n## Equivalent circuit\n# Characteristics\n## Current vs. voltage characteristics\n## Linearity\n## Spectral response\n## Noise characteristics\n## Sensitivity uniformity\n## Response speed\n# How to use\n## Connection to an op amp\n## Application circuit examples\n# Applications\n## Particle size analyzers (laser diffraction and scattering method)\n## Barcode readers\n## UV sensors\n## Rotary encoders\n## Color sensors","[{\"question\":\"What happens in a Si photodiode when illuminated by light?\",\"answer\":\"When incident light has energy greater than the band gap energy, it creates electron-hole pairs in the P-layer, depletion layer, and N-layer. The electric field in the depletion layer drives electrons toward the N-layer and holes toward the P-layer, producing a measurable current when electrodes are connected to an external circuit.\"},{\"question\":\"Which characteristics are covered for evaluating Si photodiode performance?\",\"answer\":\"The document covers current vs. voltage characteristics, linearity, spectral response, noise characteristics, sensitivity uniformity, and response speed. These are used to judge how the device responds to light level and frequency content.\"},{\"question\":\"How can Si photodiodes be used with an op amp?\",\"answer\":\"The note provides guidance for connecting the photodiode to an op amp and includes application circuit examples. These circuits support signal amplification and practical measurement in different systems.\"}]","Si photodiodes - Technical note | PDF",43]