Design: Hardware vs PCB

Many people don’t quite understand the difference between hardware and PCB design, they might ask: Isn't the PCB the hardware? Actually, there is a important difference: in the world of pcb design, hardware is a component of the final finished PCB.  In fact, hardware describes the individual components that populate a fabricated circuit board.  These can be discrete components such as resistors, capacitors, LEDs and diodes and also includes integrated circuits, power regulators, connectors, and standoffs.

They ask questions like “can you design PCB for my battery-based sensor or BMS or data logger?”

What they really mean is “can you design hardware for my product with XYZ functionality?”

I get these kinds of inquiries on daily basis.

Let me try to explain:

Hardware Design

hardware design is the stage where the engineer selects the components and figures out the circuit for each and every functionality required in the product and you do a rough BOM cost analysis so that it meets the target manufacturing cost.

For this stage to be effective you need to have a requirement document that details what is needed on a board or product.

Schematic Capture

After the hardware is frozen in the previous stage, you need to create a schematic using an EDA tool, like Altium® Designer (in my case), KiCAD, Eagle, ORCAD, etc.

This is nothing but a digital form of the circuit with which you can create the PCB design. This stage has 3 parts:

Schematic symbol creation Creating the circuit Optimization/reviews.

What is PCB Designing

In this stage, you design the PCB, basically how each IC, component will be connected on the PCB using the tracks, in its physical form.

This stage has 4 parts:- footprint creation

Actually, schematic capture and PCB designing is also part of over all hardware design only.

Above is just on high level, hope it was easy to understand and helps some of you.

Another thing which is quite challenging for less experience people in the hardware development is how the whole hardware development works.

They think, you design the hardware, prototype it, test it and it should work, 1st time right, yes, every wants this.

But, first-time-right design is a myth, you can only reduce the probability of errors by various levels of reviews and a detailed checklist.

If the product you are designing has nothing new and everything (IC, MCU) you are using is used previously in some of your other projects and you have previous experience, then yes probability of 1st time right design is quite high.

but still, there will be a chance of error.

Not many people will agree to this as they are scared to tell the truth.

This hurts their ego or fame when they accept that their design will have chances of errors in 1st prototype.

This is what I learned hard way