MDDI Article: Getting the Most Out of Your Design Review
This article originally appeared in MD+DI, written by Product Creation Studio Director of Electrical and Firmware Engineering, Mike Kahn.
Design reviews are a critical part of the product development process. Many organizations unknowingly falter when it comes to preparing for design reviews. The good news is, there are easy steps organizations can take to ensure that a design review provides the most possible value.
Consider these best practices for preparing for a design review and how to get the most out of the process when working with a design team.
Consider the tale of Brad, a talented electrical engineer who developed a complex circuit board on a very tight schedule. In a twist, the marketing team added a last-minute, must-have feature, but after Brad already started his detailed design, and with no schedule relief.
Stressed for time and trying to account for the new feature, Brad raced to complete the changes to the schematic by the deadline. Working up to the last minute, he emailed the completed schematic to the review team late in the evening before the design review the next day. During the meeting, many of Brad’s reviewers were viewing the schematic for the first time and spent much of the time in the meeting reading ahead, trying to understand what was there.
As a result, several other design issues were missed and once the first set of boards were received, Brad ended up spending many late nights and a few weekends tracking down the last set of issues with some issues intermittent and hard to reproduce. In the end, an additional board iteration was required, pushing the date to production out by over a month.
Brad, in a post mortem project review, concluded that the schedule slip and most of the problems uncovered during his initial board bring-up could have been avoided with a better-executed design review.
While it may be tempting to skip or short-cut design reviews, it’s often the case that doing so creates unnecessary chaos. Follow these six easy steps to tune your design review process and save time in product development.
1. Plan ahead and prioritize.
With a tight schedule (as in Brad’s case), adequate time for a review and review updates is often the first thing to go. Depending on the complexity of the item being reviewed, one or more days may be required. Make sure the project schedule includes time for review preparation, time for design review participants to pre-review material, and time to make identified changes.
2. Checklists are your friend.
Many critical review items are completed outside of formal design review meetings. Checklists are a great way to make sure important items are not missed and to capture institutional knowledge to avoid repeating mistakes.
Our electrical team, for example, maintains a set of checklists for review of schematics, layout, and production of fabrication documentation. Checklists enforce best practices. Some are development tool–specific, such as ensuring proper execution of automated design rule checks and CAD exports are configured with the right setting to create outputs for fabrication. Others enforce style and necessary provisions for considerations such as test, debug, risk mitigation, and manufacturability.
If Brad had followed the checklist, he would have saved at least one stressful week in the lab tracking down the last intermittent bug that resulted from a floating signal on a disconnected pin that would have been caught with a properly configured schematic design rule check.
3. Leverage the right people.
Based on the objective of the design review, the right group of people will range from the appropriate mix of disciplines, staff across the organization, or independent reviewers within the same discipline.
A reviewer with a fresh set of eyes on a technical review will not only find issues directly, but also will ask questions that provide a fresh perspective on why requirements are implemented in a certain way. Be sure to include team members who are intimately familiar with the project as well as others who are independent and seeing it for the first time.
Outside resources to consider for the technical review:
Leverage outside consultant(s), if expert or available staff is not available within your company. Brad could have engaged an engineering consulting firm to get instant access to an experienced group of electrical, firmware, and mechanical engineers who have been though many design cycles. Other outside consultants that can be leveraged to support an electrical design, such as in Brad’s case, are electromagnetic compliance specialist and safety specialists.
Leverage component suppliers’ field application engineers. On many complicated integrated circuits, especially for complex peripherals or system on chip processors, dedicated application engineers will review schematics, layout, and firmware. This is a great under-utilized resource.
Internal extended team resources to consider for reviews:
A design review at the architectural level or a technical requirements review will leverage a cross disciplinary team.
A technical requirements review, for example, adds marketing, product management, quality engineering, safety engineering, and compliance.
Take time to think about the right group of people to include in the design review and plan ahead to ensure enough notice is given in advance to provide sufficient time for the review to fit into their schedule.
4. Conduct a review kickoff meeting.
A review kickoff meeting, prior to the actual design review, is an effective strategy to ensure coverage, save overall intake time, and help engage busy reviewers not specifically assigned to the project.
Reviewers new to the project benefit from a project overview to establish context such as review objective, fidelity, constraints, and architecture. It is also important to provide a summary of key requirements that drive implementation and aspects of the design such as power, cost, form-factor, thermal, reliability, and critical performance elements.
Many reviewers who receive review content in advance may not have a chance to closely look at the material prior to the review (and some may not look at it at all!). This targeted meeting introduces the review participant to the design and reduces that chance of procrastination by eliminating common barriers.
In the review kickoff meeting, the responsible designer can provide a design overview, walk through areas of high complexity or concern, and make sure that reviewers can locate supporting material. A reviewer who is new to the design and project will then be less likely to get stuck on basic questions, allowing time to focus on the more complex elements of the design.
Additionally, rather than having everyone focus on every part of the design, reviewers can be assigned to go deep on specific areas to ensure coverage of the more complex and high-risk areas of the design.
5. Assign roles during the review meetings.
In order to get the most productive feedback during the review meetings, it is helpful to assign some critical roles. Here are some key roles:
Design owner: The design owner sets the objective and leads the meeting. The design owner should plan the agenda ahead of time and walk through elements of the design that require specific focus in a logical order.
Note taker: Assign a dedicated note taker who is not the design owner. This allows the design owner to focus on the review and feedback. The note taker should capture all feedback and action items.
Time enforcer: Assign a person to keep the meeting on track (this is often the project manager). It is easy for the meeting to get consumed by too much detail in a specific area or discuss topics that do not support review objectives. This person should have the notes taker add such topics to a “parking lot.” Discussions or meetings can then be later scheduled to specifically address them. It’s best at the start of the meeting to introduce this person’s role along with meeting time constraints and meeting objectives to ensure understanding and acceptance when a refocus is needed.
6. Tune the process.
The designer is ultimately responsible for the work product under review and has final control of how that input should be addressed. After deliberation, the responsible designer should close the loop with the reviewers by reporting how their specific feedback items will be addressed. This also includes inputs and feedback that will not be acted on with rationale provided.
At project milestones or completion, project members should tune the review process by reviewing actual problems and issues uncovered. Adjustments to the review process could be as simple as updating a checklist, including a missed organizational member, or leveraging a specific specialist at the appropriate time in the project.
Brad’s story is common. One of the biggest mistakes made when faced with a time crunch is to short cut design reviews. In fact, discovering and solving issues after fabrication of the design typically ends up costing much more in time and budget than a design review.
And Brad’s next project?
Armed with a process and a plan for communication, Brad successfully completed and delivered his schematic to team members on time, resulting in a well-executed design review, on schedule!