Electronic concepts, chosen.
Also called: Control concept · Electronics architecture · Electrical scheme · Circuit approach
Deciding the control approach, the sensing, the heater driver, the user interface and the power, picking the simplest reliable parts that meet the spec.
Choose the electronics, not gadgets. Five decisions: control, sensing, heater drive, interface, power and safety. Pick the simplest part that meets the spec and stop. Over-specify and you pay in cost, certification and parts that can fail. The worked board is below.
What electronic concepts are
The electronic concept is the answer to one question: what electronics does this product actually need to do its job? Not what it could have. What it needs. You work through five decisions in turn, and for each one you pick the simplest part that meets the written spec, then move on.
The discipline is restraint. Every part you add has to be sourced, soldered, powered, tested and certified, and every part can fail. A microcontroller you half-use is a microcontroller you fully pay for. The spec is the filter: if a requirement does not name it, the electronics should not carry it. The job is to hold the line at “enough”, because “enough” is the cheapest thing that still works.
The five decisions
- Control. What runs the logic? A fixed-function controller, a small microcontroller, or no processor at all.
- Sensing. What does the product need to measure, where, and how accurately?
- Heater drive (or actuator drive). How is the load switched, and how is it kept safe?
- Interface. How does the user set and read the thing?
- Power and safety. Where does the energy come from, and what keeps it inside the rules?
Here is the concept for the proofing box, the one that ran through our pilot, so you can see the shape of a good answer rather than a generic template.
Five decisions, five simplest-that-works answers. None of them reaches for a part the spec did not ask for. That is the whole skill.
How it fits the bigger picture
Electronic concepts is activity 06.10.05 in the framework: the last of five Design-stage activities. It sits alongside the mechanical and aesthetic concepts that come before it, and it closes Stage 06 Design. What it hands forward is the architecture that Stage 07 Engineer turns into a real schematic, a real board layout, and a real bill of materials.
What it can do
It sets the electrical direction before any detailed engineering money is spent. Choose the simplest reliable parts here and every later decision, schematic, layout, sourcing and certification, inherits a smaller, cheaper, more robust starting point. I have seen a clean concept save weeks of engineer time that a bloated one would have burned.
What it can’t do
It can’t prove the electronics work. That is Stage 07 Engineer, where the controller gets tuned, the board gets laid out, and the heater drive gets tested against BS EN 61010 for real. The concept is a committed direction, not a finished design; Engineer either confirms it or sends a part back for a rethink.
See the full 10-stage process →
Try it yourself
Take your spec. For each of the five decisions, control, sensing, drive, interface, power, write the simplest part that meets the requirement, then ask: “does the spec actually demand more than this?” If it doesn’t, stop. If you reached for a microcontroller and connectivity, check whether a fixed-function part would have done. The cheapest thing that meets the spec wins.
Want a structured first pass? Start the Free Sprint → and the GPT will help you frame the control approach before you commit to parts.
Your electronic-concept checklist
▸ From the notebook · optional reading
Project notes: the Manchester PCB partner
The proofing box’s electronics came down to one small board, one sensor and a controller. The temptation to add a chip we’d half-use was the real fight.
3 min read · click to open
Dan came to the electronics meeting with a sketch and a worry. The sketch had a capable microcontroller, Wi-Fi, and a header for “future features”. The worry was that a board without any of that would look unfinished next to the kitchen gadgets at the show.
I asked one question: “What in the spec needs the Wi-Fi?” Nothing did. The product’s whole promise was “holds the temperature, no app, no thinking.” A radio it never used would still need certifying, still need a stack to maintain, still cost parts, and still be a thing that could fail in a customer’s kitchen. We struck it.
What we settled on
A small low-voltage control board, assembled by a partner in Manchester who could do short runs without a minimum-order fight. One temperature sensor in the air space. A simple closed-loop controller driving the resistive element, capped well under 30W. A rotary encoder and a small OLED for the whole interface. Mains in through a safe low-voltage supply, the lot designed against BS EN 61010 for UKCA marking.
The bill of materials landed at £38–55. A microcontroller-plus-connectivity concept would have pushed parts cost up, dragged the certification scope out, and added firmware we would have owned forever, all to support features the spec never asked for.
The honest part: a fixed-function controller would have been simpler still, but the small microcontroller earned its place because the closed-loop tuning was cleaner in firmware than in fixed logic, and it left one safe door open for a future preset without a redesign. That was the only “future” part we kept, and only because it cost nothing now. Everything else went in the V2 backlog. Dan still wanted the Wi-Fi for the photos. We kept it out of the product and put it in a render instead.
— Design stage, project notes, 2026
— Next in Design → Concept 3D CAD