Electronics Engineering Design Report

Proof required

Submit: (1) the design brief with all quantitative requirements listed (supply, output, tolerance, bandwidth, operating conditions — at least five numbered requirements); (2) the functional block diagram with one block per design stage and the signal flow labelled; (3) a component selection table (stage, component/IC selected, key specification from datasheet, selection rationale in 1–2 sentences); (4) links to the free datasheets for all major components.

What gets checked

• Design requirements are quantitative and specific — 'output voltage: 5.0 V ± 2%; output current: 0 to 500 mA; ripple: <50 mV peak-to-peak at full load; efficiency: >75% at 250 mA load; input voltage range: 7 V to 12 V' is a valid requirements list; 'produces 5V output' is not
• Component selection rationale references the relevant datasheet specification — 'selected LM7805 because its output voltage accuracy is ±2% (datasheet Table 1), within the ±2% design requirement; its 1A current rating exceeds the 500 mA design maximum by 2×' is a valid rationale; 'commonly used regulator' is not
• Datasheet links are to free public sources — Mouser, Digikey, Texas Instruments, and STMicroelectronics all host free datasheets; no paywalled document links are acceptable

Common mistakes

• Selecting a design so simple it has only one functional stage — a single voltage divider or a single op-amp with no feedback network does not constitute a design with multiple interdependent stages; the design must have at least three functional blocks
• Listing components without referencing the datasheet specifications that justify the selection — component selection without datasheet evidence is conjecture, not engineering selection

Resources

What a verifier looks for

• Engineering Design Triad: M1 produces a design artifact (block diagram + component selection table with datasheet evidence) — this is the first of three artifact types required across M1–M3.
• Requirements list must be quantitative — check that each requirement has a number and a unit and a tolerance where applicable.
• Component selection table must reference specific datasheet specifications — check that the rationale cites a table, figure, or parameter name from the datasheet, not general knowledge.
• Datasheet links must be to free public sources — check that all links are accessible without a login or payment.
• Reviewer must be an electrical or electronics engineer with analogue circuit design experience — component selection validity requires domain-specific expertise.

Proof required

Submit: (1) the complete schematic with all component values annotated (KiCad or Falstad export/screenshot); (2) the component value calculations for at least two stages, showing the design equations and the derivation of each value; (3) the simulation results for three key parameters as screenshots or exported data — each result must be compared against the corresponding design requirement with a margin statement.

What gets checked

• Component value calculations show the design equation before the substitution — 'C = 1/(2π × f_c × R) = 1/(2π × 1000 × 10000) = 15.9 nF → select 15 nF (E24)' is a valid calculation; '15 nF selected' is not
• Three simulation results are each compared against their design requirement with a numerical margin — 'simulated output voltage: 5.03 V; requirement: 5.0 V ± 2% (4.9 V to 5.1 V); margin: within requirement ✓' is a valid margin statement
• Schematic has all component values annotated — a schematic with blank value fields (R?, C?) has not been designed, only drawn

Common mistakes

• Designing by trial and error in simulation without completing the analytical calculations first — a design that works in simulation but has no calculation derivation cannot be understood, explained, or modified by another engineer; calculations must precede simulation
• Simulating only the nominal case and not checking the boundary conditions — a power supply that works at 5 mA but fails at 500 mA has not been verified against its requirements; simulation must test at or near the design limits

Resources

What a verifier looks for

• Engineering Design Triad: M2 produces a design artifact (annotated schematic) and an analysis artifact (component value calculations + simulation results with margin statements) — both must be present.
• Calculations must show equations before substitution — check a random sample of two calculations; if they present only the final value, the derivation has been omitted.
• Three simulation results must each include a margin statement — check that each result is compared numerically against a design requirement, not just presented as a screenshot.
• Schematic must have all component values annotated — check for blank value fields.
• Reviewer must be an electrical or electronics engineer with analogue circuit design experience — component value calculation validity and simulation interpretation require discipline-specific expertise.

Proof required

Submit: (1) the complete electronics design report (all sections above); (2) the performance summary table (design requirement, simulated value, margin, pass/fail for all requirements); (3) a written record of the reviewer's two technical challenges and your responses (250 words minimum, attributing reviewer by professional role).

What gets checked

• Performance summary table covers all quantitative requirements from M1 — a table that omits some requirements has not fully verified the design; every numbered requirement from the design brief must appear as a row
• Discussion section names a specific design constraint — 'the choice of the LM7805 linear regulator constrained efficiency to approximately 55% at full load because of the high dropout voltage; a switching regulator would achieve >85% but was rejected due to EMI complexity at this design stage' is a valid constraint discussion
• Reviewer challenges are substantive and technical — 'why did you choose this IC?' with the response citing a specific datasheet parameter is substantive; 'does this design work?' is not a technical challenge

Common mistakes

• Omitting the performance summary table — this is the most important section for verifying that the design meets its requirements; a report without it is an incomplete engineering document
• Writing a discussion section that only describes what was done — the discussion must analyse why design decisions were made, what they constrained, and what could be improved; a description of the design belongs in the design approach section

Resources

What a verifier looks for

• Engineering Design Triad check: M1–M3 together produce a design artifact (block diagram + annotated schematic), an analysis artifact (component value calculations + simulation results + performance summary table), and a documentation artifact (electronics design report with discussion and conclusions) — confirm all three types are present.
• Performance summary table must cover all requirements from M1 — cross-check the table rows against the M1 requirements list; missing rows are missing verifications.
• Discussion section must analyse design decisions, not describe the design — check that the constraint and improvement discussions name specific technical reasons.
• Reviewer challenges must be recorded with specific technical content — check that the responses cite component specifications or design equations, not general statements.
• Reviewer must be an electrical or electronics engineer with analogue circuit design experience.
• The Proof Accessibility Rule applies — KiCad, LTspice, Falstad, and TI datasheet library are all free.