A PRD empowers informed, effective development decisions while serving as a goalpost, guide, and reference point throughout the development lifecycle.
Why PRDs Matter: A Perspective from Engineering Leadership
A great Product Requirements Document (PRD) is both powerful and essential, yet often difficult to define and even harder to craft well. In this article, I share my perspective on PRDs, shaped by years of experience as a designer, manager, and director.
At its core, a PRD articulates what a product is and why it matters. It focuses on the problem being solved, the usecases, the target users, the business rationale, and the broader product vision.
Unlike a product specification, which details features and functionalities, the PRD provides strategic context framing the problem space, defining the audience, and aligning with business objectives.
A well-crafted PRD informs the critical go/no-go decision before significant resources are committed.
It’s a tool for clarity: refining and contextualizing a product idea so stakeholders can make confident, informed decisions. Beyond that initial decision, the PRD serves as a guiding reference throughout development of a goalpost, a roadmap, and a touchstone that keeps teams aligned and focused.
Crafting a Product Requirements Document (PRD) for Semiconductor Products: An Engineering Leader’s Journey
Back when I was a young engineer, hunched over a desk debugging RTL code at 2 a.m., I thought the hardest part of building a chip was getting the design right. Years later, as a leader herding teams through tight tape-out schedules and now as a director wrestling with multi-million-dollar product decisions, I’ve learned the real challenge often starts before a single line of Verilog is written: it’s crafting a Product Requirements Document (PRD) that actually works.
A great PRD isn’t just a document it’s a shared vision that keeps everyone, from designers to marketers, pulling in the same direction.
I’ve seen PRDs that sparked brilliant chips and others that led to costly missteps and program cancellations.
Drawing from those lessons, this article outlines how to create a PRD for semiconductor products, with a focus on clarity, structure, and semiconductor-specific examples. It’s a deep dive into what a PRD must include, what it should avoid, and how it fits into the broader development ecosystem.
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The Role of a PRD in Semiconductor Development
A PRD is the heartbeat of a semiconductor project.
It defines what the product is, why it matters, and who it serves, without getting bogged down in how it will be built.
In an industry where a single tape-out can cost millions and take years, the PRD is the linchpin for the go/no-go decision which ensures resources are committed only when the vision is clear and the market need is validated. It’s also a guiding star throughout development, aligning product management, engineering, manufacturing, and marketing teams through the grueling journey from concept to silicon.
Example: PRD for a Low-Power IoT Microcontroller
Imagine a PRD for a low-power microcontroller (MCU) for Internet of Things (IoT) devices. It would highlight the need for a chip that extends battery life in smart sensors, targeting IoT device makers. The PRD might specify 50 MHz performance at <10 µA/MHz power consumption but leave choices like ARM Cortex cores or 22nm process nodes to technical specifications.
Key Components of a Semiconductor PRD
A PRD must be comprehensive yet concise, balancing strategic vision with actionable requirements. Authored by a Product Manager with input from cross-functional stakeholders (e.g., engineering, design, client success, and marketing), it should include the following sections, tailored for semiconductors:
Summary
- What it is: A brief overview of the product and its significance, limited to 2–3 sentences.
- Why it matters: Sets the stage for stakeholders, especially decision-makers, to grasp the product’s purpose quickly.
- Semiconductor Example: “This low-power IoT microcontroller enables year-long battery life in smart sensors, targeting IoT device manufacturers to capture a $500M market opportunity.”
- Do: Keep it concise and compelling, focusing on the product’s core value.
- Don’t: Include technical details or vague statements like “build a great chip.”
Fundamental Problem(s)
- What it is: A clear, focused description of the market or technical problem(s) the product addresses, without proposing solutions.
- Why it matters: Grounds the project in a validated need, ensuring focus and minimizing scope creep.
- Semiconductor Example: “IoT device manufacturers struggle with high power consumption in current MCUs (50 µA/MHz), limiting smart sensor battery life to 6 months. Customers demand <10 µA/MHz at 50 MHz to enable year-long operation, based on 2024 market research and feedback from 10 key OEMs.”
- Do: Use data (e.g., customer feedback, market reports) to quantify the problem and keep the scope tight.
- Don’t: Propose solutions (e.g., “use a 22nm process”) or address multiple unrelated problems.
External Commitments
- What it is: Obligations to external stakeholders, such as promised features, timelines, or certifications.
- Why it matters: Ensures transparency and alignment on non-negotiable deliverables.
- Semiconductor Example:
- Commitment: “Deliver an MCU with BLE 5.2 and AEC-Q100 qualification by Q3 2026.”
- Who/Context: “Promised to key IoT OEM customer in a Q1 2025 contract.”
- Flexibility/Consequences: “Limited flexibility on timeline due to customer product launch; non-fulfillment risks losing $10M contract.”
- References: “Q1 2025 contract, Slack thread #iot-mcu-deals.”
- Do: Specify who made the commitment, its context, and consequences of failure.
- Don’t: Omit references or vaguely state “we promised something.”
Internal Commitments
- What it is: Internal obligations, such as leadership directives or cross-team dependencies.
- Why it matters: Clarifies internal expectations to prevent misalignment.
- Semiconductor Example:
- Commitment: “Use TSMC 22nm process to leverage existing IP portfolio.”
- Who/Context: “Directed by VP of Engineering in Q4 2024 planning.”
- Flexibility/Consequences: “No flexibility due to IP compatibility; deviation requires re-licensing costing $2M.”
- References: “Q4 2024 engineering roadmap, email thread ‘IP Strategy.’”
- Do: Mirror the structure of external commitments for consistency.
- Don’t: Assume internal alignment without documenting commitments.
Additional Impact
- What it is: Broader benefits beyond solving the core problem, such as efficiency gains or strategic advantages.
- Why it matters: Highlights the product’s value to the organization and future opportunities.
- Semiconductor Example:
- Efficiency: “Reduces customer support queries for power issues by 50%.”
- Strategic: “Strengthens our position as a low-power MCU leader, deepening market moat.”
- Opportunities: “Enables future AI-enabled MCU variants for edge computing.”
- Do: Tie impacts to business goals and future potential.
- Don’t: Overpromise unvalidated benefits (e.g., “revolutionizes IoT”).
Scale
- What it is: A rough estimate of time, resources, and complexity, often compared to past projects.
- Why it matters: Informs resource allocation and feasibility.
- Semiconductor Example: “Development requires 18 months and $10M, similar to Project X (12-month MCU) but larger due to BLE 5.2 integration and AEC-Q100 testing.”
- Do: Use past projects as benchmarks and consult engineering for estimates.
- Don’t: Provide overly precise estimates without validation.
Finance
- What it is: A business case covering costs, revenue, and long-term viability.
- Why it matters: Justifies investment and aligns with financial goals.
- Semiconductor Example:
- Build Cost: “$10M for design, IP licensing, and tape-out.”
- Operating Cost: “$1M/year for support and updates.”
- Revenue: “$50M annual revenue from 10% IoT MCU market share.”
- Viability: “5-year product lifecycle, with potential for derivative products.”
- Do: Acknowledge estimate uncertainty and justify figures with stakeholder input.
- Don’t: Overlook indirect costs (e.g., support) or assume guaranteed revenue.
User Profiles
- What it is: Brief descriptions of target users, their problems, and how the product helps.
- Why it matters: Ensures the product is user-centric.
- Semiconductor Example: “Embedded systems engineers at IoT device manufacturers need low-power MCUs with BLE 5.2 to build smart home sensors. OEMs require cost-effective chips (<$2/unit) for high-volume production.”
- Do: Reference existing personas and focus on user-product interaction.
- Don’t: Include full persona details or generic descriptions (e.g., “all engineers”).
Product Vision
- What it is: A high-level statement of the product’s purpose and long-term impact.
- Why it matters: Inspires teams and provides a guiding vision.
- Semiconductor Example: “To empower IoT device manufacturers with a microcontroller that delivers industry-leading power efficiency and seamless connectivity, enabling smarter, longer-lasting smart home and healthcare devices.”
- Do: Focus on user impact and market differentiation.
- Don’t: Include specific features (e.g., “BLE 5.2 support”) or technical details.
Functional Requirements
- What it is: High-level capabilities the product must have to solve the problem.
- Why it matters: Defines what the product does to meet user needs.
- Semiconductor Example:
- “Support BLE 5.2 for reliable smart home hub connectivity.”
- “Enable 50 MHz processing for real-time IoT applications.”
- “Provide configurable I/O for sensor integration.”
- Do: Use user stories (e.g., “As an engineer, I need…”) and prioritize requirements.
- Don’t: Specify implementation (e.g., “use ARM Cortex-M4”) or detailed feature lists.
Non-Functional Requirements
- What it is: Constraints on how the product operates, such as performance, reliability, or cost.
- Why it matters: Defines the quality and boundaries of functionality.
- Semiconductor Example:
- Performance: “<10 µA/MHz in active mode, <1 µA in sleep mode.”
- Reliability: “Meet AEC-Q100 qualification for automotive use.”
- Cost: “Production cost under $2/unit at 1M units.”
- Do: Use measurable metrics and align with user needs.
- Don’t: Include overly specific targets (e.g., “1.2V operating voltage”) that limit engineering.
Features and Use Cases
- What it is: Broad descriptions of how the product delivers functionality and how users interact with it.
- Why it matters: Illustrates how requirements translate to user value, without overlapping with technical specs.
- Semiconductor Example:
- Feature: “Low-power connectivity module.”
- Use Case: “An embedded engineer configures the MCU to connect a motion sensor to a smart home hub via BLE 5.2, enabling real-time alerts with minimal power draw.”
- Do: Keep descriptions high-level (1–2 sentences) and tie to requirements.
- Don’t: Include detailed UI or implementation (e.g., “firmware UI with three tabs”).
Scope and Non-Goals
- What it is: A clear boundary of what’s included and excluded in the product.
- Why it matters: Prevents scope creep and maintains focus.
- Semiconductor Example:
- In Scope: “Low-power MCU with BLE 5.2 and 50 MHz performance.”
- Out of Scope: “5G connectivity or AI acceleration, reserved for future revisions.”
- Do: Explicitly list non-goals to avoid confusion.
- Don’t: Leave scope ambiguous or include speculative features.
Existing Environment
- What it is: Relevant products, standards, tools, or regulations impacting the project.
- Why it matters: Provides context for development and identifies opportunities or challenges.
- Semiconductor Example:
- Help: “Existing BLE 5.2 IP library reduces development time.”
- Hindrances: “AEC-Q100 qualification requires additional testing; mitigated by early validation.”
- Peripheral: “Wi-Fi connectivity seems relevant but is out of scope due to power constraints.”
- Do: Address competitors, standards, and mitigation strategies.
- Don’t: Ignore regulations (e.g., RoHS compliance) or assume a clean slate.
Integration Profiles
- What it is: Systems or tools the product will interact with programmatically.
- Why it matters: Clarifies technical dependencies for engineering.
- Semiconductor Example: “The MCU integrates with IAR Embedded Workbench for firmware development and connects to smart home hubs via BLE 5.2.”
- Do: Summarize key integrations tied to “Help” items in Existing Environment.
- Don’t: Include detailed APIs or protocols (e.g., “use specific BLE stack”).
Dependencies and Risks
- What it is: External factors (e.g., IP licensing, fab capacity) and risks (e.g., supply chain delays).
- Why it matters: Enables proactive planning and risk mitigation.
- Semiconductor Example:
- Dependencies: “Requires BLE 5.2 IP licensing by Q1 2026.”
- Risks: “Potential TSMC 22nm fab delays due to high demand; risk of failing AEC-Q100 qualification.”
- Do: Quantify risks and specify dependencies.
- Don’t: Overlook supply chain or certification challenges.
OKRs (Objectives and Key Results)
- What it is: A framework for defining and measuring success.
- Why it matters: Aligns teams on goals and tracks progress.
- Semiconductor Example:
- Objective: “Establish leadership in low-power IoT MCUs.”
- Key Results: “Achieve 10% market share by Q4 2027; secure 3 major OEM design wins by Q2 2027.”
- Do: Use qualitative objectives with quantifiable key results.
- Don’t: Set vague goals (e.g., “improve market position”).
KPIs (Key Performance Indicators)
- What it is: Quantifiable metrics to monitor performance and support OKRs.
- Why it matters: Provides operational insights and baselines for future goals.
- Semiconductor Example:
- “Power consumption (µA/MHz),” “Customer acquisition cost,” “Design win conversion rate.”
- Baseline: “Current MCU power consumption: 50 µA/MHz; target: <10 µA/MHz.”
- Do: Include metrics tied to OKRs and operational performance.
- Don’t: Use engineering-only metrics (e.g., “gate count”).
Version Control and Change Log
- What it is: A record of PRD updates, with version numbers and change summaries.
- Why it matters: Ensures transparency as requirements evolve.
- Semiconductor Example:
- “v1.0 (Jan 2025): Initial draft with problem statement and requirements.”
- “v1.1 (Mar 2025): Added BLE 5.2 and updated power targets.”
- Do: Use clear versioning and summarize changes.
- Don’t: Treat the PRD as static.
What a PRD Should Not Include
To maintain clarity, avoid these common pitfalls, especially in semiconductors:
- Implementation Details: Don’t specify how to meet requirements (e.g., “use TSMC 22nm” or “ARM Cortex-M4”). These belong in architectural specs.
- Detailed Feature Lists: Avoid exhaustive breakdowns (e.g., “16 GPIO pins, 2 UARTs”). Focus on high-level needs (e.g., “flexible I/O”).
- Unvalidated Assumptions: Don’t assume market needs (e.g., “customers want 20% better power”) without data.
- Overly Prescriptive UX: Avoid dictating firmware UI details (e.g., “configuration tool with three tabs”). Focus on user needs (e.g., “easy configuration”).
- Premature Optimization: Don’t lock in specific targets (e.g., “1.2V voltage”) that limit engineering flexibility.
- Excessive Length: Keep the PRD to 5–10 pages, moving non-critical details to appendices or specs.
Relationship to Other Documents
The PRD is part of a broader ecosystem of documents, each with a distinct role:
- Marketing Requirements Document (MRD):
- Purpose: Defines market opportunity, customer demand, and competitive landscape.
- Relationship to PRD: The MRD provides market context; the PRD translates it into product requirements. For example, an MRD might note “$500M IoT MCU opportunity,” and the PRD specifies “<10 µA/MHz.”
- Key Difference: MRD is market-driven (external); PRD is product-driven (internal).
- Semiconductor Example: MRD highlights “competitors lack BLE 5.2.” PRD requires “BLE 5.2 for smart home connectivity.”
- Architectural Specification:
- Purpose: Outlines system architecture (e.g., block diagrams, IP selection).
- Relationship to PRD: PRD sets requirements (e.g., “50 MHz performance”); architectural spec proposes solutions (e.g., “Cortex-M4 on 22nm”).
- Key Difference: PRD is solution-agnostic; architectural spec is solution-specific.
- Semiconductor Example: PRD demands “real-time processing.” Architectural spec selects “Cortex-M4 with DVFS.”
- Technical Specification:
- Purpose: Details implementation (e.g., circuit designs, pin assignments).
- Relationship to PRD: Translates PRD requirements into engineering deliverables.
- Key Difference: PRD focuses on what and why; technical spec focuses on how.
- Semiconductor Example: PRD requires “AEC-Q100 qualification.” Technical spec details “-40°C to 125°C testing.”
- Test and Validation Plan:
- Purpose: Defines how to verify requirements (e.g., performance, reliability tests).
- Relationship to PRD: PRD success metrics (e.g., “<10 µA/MHz”) inform test criteria.
- Key Difference: PRD defines success; test plan proves it.
- Semiconductor Example: PRD requires “<1 µA sleep mode.” Test plan specifies “measure with Keithley 2450 SourceMeter.”
Structuring for the Audience
- For Decision-Makers: Prioritize Summary, Fundamental Problems, External/Internal Commitments, Additional Impact, Scale, Finance, OKRs, and KPIs to support go/no-go decisions.
- For Development Teams: Emphasize Functional/Non-Functional Requirements, Features and Use Cases, Integration Profiles, and Existing Environment, with Scale and Finance as context.
Best Practices for Crafting a Semiconductor PRD
- Collaborate Early: Engage product management, engineering, manufacturing, and marketing upfront. For example, confirm TSMC 22nm availability with the fab team.
- Keep It Lean: Aim for 5–10 pages, using appendices for supporting data (e.g., market research).
- Ground in Data: Use customer feedback, market reports, or benchmarks (e.g., “80% of IoT OEMs prioritize battery life, per 2024 survey”).
- Prioritize and Iterate: Mark requirements as “must-have” or “nice-to-have” and update with version control.
- Balance Flexibility and Structure: Set boundaries (e.g., “<1.5V operation”) but allow engineering creativity.
- Use Collaborative Tools: Use Confluence or Notion for real-time updates, linking to Jira for traceability.
- Avoid Pitfalls:
- Scope Too Large: Break large problems into smaller projects (e.g., focus on BLE 5.2 now, AI later).
- PRD Too Large/Detailed: Move details to specs or appendices.
- Missing Information: Consult stakeholders to fill gaps (e.g., concurrent user requirements).
The PRD’s Role in the Semiconductor Lifecycle
- Pre-Development: Justifies investment (e.g., “$10M for $500M IoT MCU market”).
- Development: Guides architecture, design, and verification (e.g., power targets shape DVFS).
- Post-Launch: Evaluates success (e.g., “did we hit <10 µA/MHz?”) and informs iterations.
Example PRD Outline for a Semiconductor Product
Product Requirements Document: Low-Power IoT Microcontroller
**Version**: 1.0 (Jan 2025)
**Owner**: [Product Manager Name]
1. Summary
This low-power IoT microcontroller enables year-long battery life in smart sensors, targeting IoT device manufacturers to capture a $500M market opportunity.
2. Fundamental Problem(s)
IoT device manufacturers face high power consumption (50 µA/MHz), limiting smart sensor battery life to 6 months. Customers demand <10 µA/MHz at 50 MHz for year-long operation, per 2024 OEM feedback.
3. External Commitments
- Commitment: Deliver MCU with BLE 5.2 and AEC-Q100 qualification by Q3 2026.
- Who/Context: Promised to key IoT OEM in Q1 2025 contract.
- Flexibility/Consequences: Limited flexibility; non-fulfillment risks $10M contract.
- References: Q1 2025 contract, Slack #iot-mcu-deals.
4. Internal Commitments
- Commitment: Use TSMC 22nm process for IP compatibility.
- Who/Context: Directed by VP of Engineering, Q4 2024.
- Flexibility/Consequences: No flexibility; deviation costs $2M in re-licensing.
- References: Q4 2024 roadmap, email ‘IP Strategy.’
5. Additional Impact
- Efficiency: Reduce power-related support queries by 50%.
- Strategic: Strengthen low-power MCU leadership.
- Opportunities: Enable AI-enabled MCU variants for edge computing.
6. Scale
18 months, $10M, similar to Project X but larger due to BLE 5.2 and AEC-Q100.
7. Finance
- Build Cost: $10M (design, IP, tape-out).
- Operating Cost: $1M/year (support, updates).
- Revenue: $50M/year from 10% market share.
- Viability: 5-year lifecycle, potential for derivatives.
8. User Profiles
Embedded engineers need low-power MCUs with BLE 5.2 for smart sensors. OEMs require cost-effective chips (<$2/unit) for high-volume production.
9. Product Vision
Empower IoT manufacturers with a microcontroller delivering unmatched power efficiency and connectivity for smarter, longer-lasting devices.
10. Functional Requirements
- Support BLE 5.2 for smart home connectivity.
- Enable 50 MHz processing for real-time IoT applications.
- Provide configurable I/O for sensor integration.
11. Non-Functional Requirements
- Performance: <10 µA/MHz active, <1 µA sleep mode.
- Reliability: Meet AEC-Q100 qualification.
- Cost: Production cost < $2/unit at 1M units.
12. Features and Use Cases
- Feature: Low-power connectivity module.
- Use Case: Engineer configures MCU to connect motion sensor to smart home hub via BLE 5.2, enabling real-time alerts with minimal power.
13. Scope and Non-Goals
- In Scope: Low-power MCU with BLE 5.2, 50 MHz.
- Out of Scope: 5G connectivity, AI acceleration.
14. Existing Environment
- Help: BLE 5.2 IP library reduces development time.
- Hindrances: AEC-Q100 requires testing; mitigated by early validation.
- Peripheral: Wi-Fi connectivity out of scope due to power constraints.
15. Integration Profiles
Integrates with IAR Embedded Workbench for firmware and smart home hubs via BLE 5.2.
16. Dependencies and Risks
- Dependencies: BLE 5.2 IP licensing by Q1 2026.
- Risks: TSMC 22nm fab delays, AEC-Q100 qualification issues.
17. OKRs
- Objective: Establish low-power IoT MCU leadership.
- Key Results: 10% market share by Q4 2027; 3 OEM design wins by Q2 2027.
18. KPIs
- Power consumption (µA/MHz), customer acquisition cost, design win conversion rate.
- Baseline: Current MCU at 50 µA/MHz; target <10 µA/MHz.
19. Change Log
- v1.0 (Jan 2025): Initial draft with problem statement and requirements.
A semiconductor PRD is more than paperwork, it’s the foundation for turning a bold idea into a chip that powers the future. By clearly defining the problem, aligning with business goals, and balancing stakeholder needs, it ensures teams stay focused through the complexities of chip design. With collaboration, data-driven clarity, and iterative refinement, a PRD becomes the roadmap that transforms vision into reality, one silicon wafer at a time.
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