--- title: "SiMD, Software in a Medical Device | MedTech Terms" description: "Software embedded in or required to operate a hardware medical device. Plain-English Software & AI definition for MedTech teams, with examples and related terms" lang: en json-ld: | { "@context": "https://schema.org", "@graph": [ { "@type": "DefinedTerm", "@id": "https://medtechterms.com/terms/simd#term", "name": "Software in a Medical Device", "alternateName": "SiMD", "description": "Software in a Medical Device (SiMD) refers to software that is embedded within, or required for, the operation of a hardware medical device - such as firmware controlling an infusion pump or imaging system.", "url": "https://medtechterms.com/terms/simd", "termCode": "simd", "inDefinedTermSet": { "@type": "DefinedTermSet", "name": "MedTech Terms", "url": "https://medtechterms.com/terms" } }, { "@type": "Article", "@id": "https://medtechterms.com/terms/simd#article", "headline": "SiMD, Software in a Medical Device", "description": "Software embedded in or required to operate a hardware medical device.", "url": "https://medtechterms.com/terms/simd", "mainEntityOfPage": { "@type": "WebPage", "@id": "https://medtechterms.com/terms/simd" }, "about": { "@id": "https://medtechterms.com/terms/simd#term" }, "articleSection": "Software & AI", "inLanguage": "en", "keywords": "Software in a Medical Device, SiMD, Software & AI, medical device, MedTech", "author": { "@type": "Person", "name": "Christian Espinosa", "jobTitle": "Founder, Blue Goat Cyber", "url": "https://bluegoatcyber.com" }, "publisher": { "@type": "Organization", "name": "MedTech Terms", "url": "https://medtechterms.com" }, "isPartOf": { "@type": "WebSite", "name": "MedTech Terms", "url": "https://medtechterms.com" }, "datePublished": "2026-05-05", "dateModified": "2026-05-05", "citation": [ { "@type": "CreativeWork", "name": "FDA Software Functions", "url": "https://www.fda.gov/medical-devices/digital-health-center-excellence/device-software-functions-including-mobile-medical-applications", "publisher": { "@type": "Organization", "name": "FDA" } }, { "@type": "CreativeWork", "name": "FDA - AI/ML-Enabled Medical Devices", "url": "https://www.fda.gov/medical-devices/software-medical-device-samd/artificial-intelligence-and-machine-learning-aiml-enabled-medical-devices", "publisher": { "@type": "Organization", "name": "FDA" } }, { "@type": "CreativeWork", "name": "IMDRF - Software as a Medical Device", "url": "https://www.imdrf.org/working-groups/software-medical-device-samd", "publisher": { "@type": "Organization", "name": "IMDRF" } } ], "mentions": [ { "@type": "DefinedTerm", "@id": "https://medtechterms.com/terms/samd#term", "name": "Software as a Medical Device", "alternateName": "SaMD", "url": "https://medtechterms.com/terms/samd" }, { "@type": "DefinedTerm", "@id": "https://medtechterms.com/terms/iec-62304#term", "name": "IEC 62304", "url": "https://medtechterms.com/terms/iec-62304" } ] }, { "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://medtechterms.com/" }, { "@type": "ListItem", "position": 2, "name": "Terms", "item": "https://medtechterms.com/terms" }, { "@type": "ListItem", "position": 3, "name": "Software & AI", "item": "https://medtechterms.com/terms?cat=Software%20%26%20AI" }, { "@type": "ListItem", "position": 4, "name": "Software in a Medical Device", "item": "https://medtechterms.com/terms/simd" } ] }, { "@type": "FAQPage", "@id": "https://medtechterms.com/terms/simd#faq", "mainEntity": [ { "@type": "Question", "name": "How does SiMD differ from Software as a Medical Device (SaMD)?", "acceptedAnswer": { "@type": "Answer", "text": "SiMD is integral to the functioning of a hardware medical device and is regulated as part of that device. SaMD, in contrast, is software that itself constitutes a medical device and performs a medical function without being part of a hardware medical device." } }, { "@type": "Question", "name": "Is SiMD subject to IEC 62304?", "acceptedAnswer": { "@type": "Answer", "text": "Yes, SiMD is subject to IEC 62304, " } }, { "@type": "Question", "name": "Does SiMD need to comply with cybersecurity regulations?", "acceptedAnswer": { "@type": "Answer", "text": "Yes, SiMD must comply with applicable cybersecurity regulations and guidance, such as FDA's " } } ] } ] } --- [ MedTech Terms The authoritative reference ](/) Browse Learn [Latest](/latest) About 1. [Home](/) 2. / 3. [Terms](/terms) 4. / 5. [Software & AI](/terms?cat=Software%20%26%20AI) 6. / 7. Software in a Medical Device [All terms](/terms) Software & AI [Software Lifecycle](/ecosystems/software-lifecycle)SiMD /sim-dee/ # Software in a Medical Device Software embedded in or required to operate a hardware medical device. Reviewed by [Christian Espinosa, Founder, Blue Goat Cyber](/authors/christian-espinosa) Last reviewed May 5, 2026 ## Definition Software in a Medical Device (SiMD) refers to software that is embedded within, or required for, the operation of a hardware medical device - such as firmware controlling an infusion pump or imaging system. What the regulation says Software in a Medical Device (SiMD) is considered a component of a hardware medical device and is regulated as such, rather than as a standalone medical device. The FDA addresses this in its guidance on " [Software as a Medical Device](/terms/samd) (SaMD): Clinical Evaluation," clarifying that SiMD falls under the regulatory framework of the device it enables. Similarly, under the [EU Medical Device Regulation](/terms/mdr) (EU [MDR](/terms/mdr-reporting)) 2017/745, SiMD is subject to the [general safety and performance requirements](/terms/gspr) (GSPRs) applicable to the overall medical device, as outlined in Annex I. ## What this means in practice Unlike [SaMD](/terms/samd), SiMD is regulated as part of the parent device. It is still subject to [IEC 62304](/terms/iec-62304), cybersecurity requirements, and [design controls](/terms/design-controls). ## Examples - Firmware that controls the delivery mechanism and dosage calculations of an insulin pump is an example of SiMD. - Software embedded in an MRI machine that processes imaging data and controls the scanner's operations is considered SiMD. - The operating system and user interface software on a patient monitor that displays vital signs is an instance of SiMD. Common pitfalls - • Failing to integrate SiMD development and maintenance into the overall medical device's lifecycle management processes can lead to regulatory non-compliance. - • Overlooking the specific cybersecurity risks associated with integrated software can compromise the safety and effectiveness of the medical device. - • Treating SiMD with less rigor than standalone software regarding design controls and validation activities is a common mistake. - • Assuming that general software development practices are sufficient without adapting them to medical device regulations is a pitfall. - • Neglecting to update SiMD in response to new cybersecurity threats or operating system changes can lead to vulnerabilities and regulatory issues. ## Frequently asked questions How does SiMD differ from Software as a Medical Device (SaMD)? SiMD is integral to the functioning of a hardware medical device and is regulated as part of that device. [SaMD](/terms/samd), in contrast, is software that itself constitutes a medical device and performs a medical function without being part of a hardware medical device. Is SiMD subject to IEC 62304? Does SiMD need to comply with cybersecurity regulations? ## Cross-references ### Governed by Regulations or standards this term must comply with. - [ IEC 62304 ](/terms/iec-62304) ### Often confused with Distinct concept frequently mistaken for this one. - [ Software as a Medical Device(SaMD) SaMD is standalone software; SiMD is software inside a device. ](/terms/samd) ## Related terms Grouped by theme ### Editor's picks · Hand-selected related concepts [ Software & AI Software as a Medical Device(SaMD) Software intended for medical purposes that performs without being part of a hardware device. ](/terms/samd)[ Standards IEC 62304 Lifecycle requirements for medical device software. ](/terms/iec-62304) ### SaMD & AI/ML Devices · From this learning path [ Software & AI Clinical Decision Support(CDS) Software providing healthcare professionals with knowledge and patient-specific information. ](/terms/cds?from=samd-and-ai)[ Software & AI Predetermined Change Control Plan(PCCP) FDA mechanism to pre-authorize specific modifications to AI/ML-enabled devices. ](/terms/ai-ml-pccp?from=samd-and-ai)[ Software & AI Software of Unknown Provenance(SOUP) Software not developed for medical device use, or lacking adequate development records, incorporated into a device. ](/terms/soup?from=samd-and-ai)[ Software & AI Software Safety Classification IEC 62304 classes A, B, C reflecting potential harm from software failure. ](/terms/software-safety-class?from=samd-and-ai) ### Software Team Onboarding · From this learning path [ Cybersecurity Section 524B of the FD&C Act(524B) The federal statute that gives FDA explicit premarket authority over cybersecurity for cyber devices. ](/terms/section-524b?from=software-team-onboarding)[ Cybersecurity Secure Product Development Framework(SPDF) A documented, risk-based set of processes that build cybersecurity into a medical device across its full lifecycle. ](/terms/spdf?from=software-team-onboarding)[ Cybersecurity Software Bill of Materials(SBOM) A machine-readable inventory of all software components, including open-source and third-party libraries, used to build a medical device. ](/terms/sbom?from=software-team-onboarding)[ Cybersecurity Threat Modeling A structured analysis that identifies how an attacker could compromise a medical device and what controls mitigate each threat. ](/terms/threat-modeling?from=software-team-onboarding) Cited by Where this term appears across MedTech Terms. Learning paths (2) - [SaMD & AI/ML Devices](/paths/samd-and-ai)Lesson 2 of 9 - [Software Team Onboarding](/paths/software-team-onboarding)Lesson 2 of 12 Ecosystems (1) - [Software Lifecycle](/ecosystems/software-lifecycle) Comparisons (1) - [SaMD vs SiMD](/compare/samd-vs-simd)vs Software as a Medical Device ## Primary references 3 sources Link health: 3 verified · last checked 2026-06-20 FDA· 2 IMDRF· 1 1. [1 FDA Software Functions Verified FDA · fda.gov ](https://www.fda.gov/medical-devices/digital-health-center-excellence/device-software-functions-including-mobile-medical-applications) 2. [2 FDA - AI/ML-Enabled Medical Devices Verified FDA · fda.gov ](https://www.fda.gov/medical-devices/software-medical-device-samd/artificial-intelligence-and-machine-learning-aiml-enabled-medical-devices) 3. [3 IMDRF - Software as a Medical Device Verified IMDRF · imdrf.org ](https://www.imdrf.org/working-groups/software-medical-device-samd) Inline markers like \[1\] jump to the matching reference above. Sponsor note ### Building software-as-a-medical-device? We help SaMD and AI/ML device teams meet IEC 62304 and the FDA's evolving expectations for software cybersecurity. [Book a 30-minute discovery session](https://go.bluegoatcyber.com/meetings/blue-goat-cyber/discovery-session) - No obligation - Expert-led from minute one - NDA available on request MedTech Terms is a community resource sponsored by [Blue Goat Cyber](https://bluegoatcyber.com). Definitions are independent of any vendor. On this term Category Software & AI Acronym SiMD Sources 3 Updated 5/5/2026 [Compare with another term](/compare?a=simd) Learn in 60 seconds Card Lesson Quiz Software embedded in or required to operate a hardware medical device. - · Unlike SaMD, SiMD is regulated as part of the parent device. - · It is still subject to IEC 62304, cybersecurity requirements, and design controls. Remember this Watch out: Failing to integrate SiMD development and maintenance into the overall medical device's lifecycle management processes can lead to regulatory non-compliance. Related terms - [Software as a Medical Device(SaMD) ](/terms/samd) - [IEC 62304 ](/terms/iec-62304) You may also need Auto-suggested from Software & AI and shared keywords. - [Hardcoded Credentials ](/terms/hardcoded-credentials) - [Algorithm Change Protocol(ACP) ](/terms/algorithm-change-protocol) - [Medical Device Data System(MDDS) ](/terms/mdds) - [Medjacking ](/terms/medjacking) - [AAMI TIR45(TIR45) ](/terms/aami-tir45) - [Clinical Decision Support(CDS) ](/terms/cds) [All Software & AI terms](/terms?cat=Software%20%26%20AI) From the Blue Goat network Related resources and services on this topic. - [ AI SaMD Insights How AI is changing SaMD - risk, regulation, and good machine-learning practice. ](https://ai-samd.com) - [ Med Device Cyber Podcast Conversations with medical device cybersecurity practitioners. ](https://mdcpodcast.com) MedTech Terms An authoritative, plain-language reference for the regulatory, quality, cybersecurity, and software terms that shape modern medical devices. 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