5 Electronics Design Mistakes To Avoid At All Cost

electronic circuit design common mistakes

Written by Andrea Rossi

04/12/2021

Developing an electronics product is no walk in the park. It requires much more than building a circuit out of electronic components. Hardware designers need to keep their eyes on various aspects of risk complications when the design is sent for manufacturing.

These are common mistakes that have proved to be costly for designers and their companies.

 

1. Failure To Optimize For DFM

DFM or design for manufacturing refers to approaches in electronics design that optimizes the product for manufacturing. Hardware designers can sometimes be engrossed in getting the circuit to work but neglect the DFM optimization of the design. As a result, manufacturers have trouble fabricating reliable PCBs or getting the assembly done without hiccups. Even if they could, not implementing DFM may result in a higher cost per product. Eventually, the increased cost and possible reliability issues will affect the company’s bottom line.

For example, inexperienced designers may forget to include fiducial markers and tooling strips on the PCB. This can be disastrous if the PCB is mounted with SMD components, particularly QFP or BGA ICs. Assemblers require the fiducial markers to accurately placed fine-pitched SMD components and the tooling strip for securing the PCB on the machine. Even slight mistakes of not aligning ICs to the same orientation can delay the production schedule. It makes the pick-and-place process inefficient as each of the components needs to be rotated at different angles prior to mounting.

If you’re working with a Shenzhen manufacturer, you can confirm if your design is manufacturing-friendly before starting the manufacturing process.

 

2. Committing RF Design Mistakes

Working with RF design is much more challenging than its lower-frequency counterpart. The slightest mistakes can cause post-production issues if they are not detected during testing. Impedance matching is crucial in RF circuits to prevent signal reflection. If the transceiver and the antenna have mismatched impedance, you’ll find that the transmitted signal suffers from degradation due to the reflected signals.

Generally, RF circuits are built to work with 50 Ohm impedance. Therefore, you’ll want to ensure that the components and traces are designed for 50 Ohm. The tough part is keeping the PCB trace at equal impedance to the source and load. The characteristic impedance of PCB traces is influenced by a few factors, including PCB material, trace width, height, and board thickness. Keep trace lengths to the minimum and avoid vias on the traces to ensure uniformity of the impedance.

Besides impedance matching, you’ll also need to ensure that the RF circuit is not creating EMI issues to adjacent circuits. It’s also important to maintain a continuous ground plane below the high-frequency RF trace to prevent a ground loop.

Consider better materials if FR-4 is not suitable for your RF design. You can consult with Szenzhen manufacturers as they are experienced in producing high-frequency RF circuits.

 

New Product Manufacturing in China

3. Cost Estimation Is Done Too Late

Building a functional electronics product and is different from putting a profitable product to the market. The difference lies in getting a cost estimation done before the design even started.

You don’t want to wait until you’ve completed the PCB layout until you start checking out the cost for each component, setup, and assembly. It’s a mistake to assume that you’ll get a favorable cost for all the components when you’re purchasing in bulk.

Some components are expensive, even in a larger quantity. Newly-introduced components which are yet to be manufactured in volume can result in higher cost. Ultimately, it isn’t viable to proceed with a design if it costs more than the selling price.

Therefore, it’s best to get a cost estimate before you kick off with the design. Usually, it’s the IC, PCB fabrication, and assembly that made up a huge portion of the cost. Check out with the IC manufacturer on availability and pricing, or partner with ICS to get high-quality components from Shenzhen while staying within budget.

 

4. Product Enclosure Is Not DFM-Optimized

DFM is not limited to electronics design. If your electronics product involves an enclosure, which most do, you’ll need to ensure that it is optimized for manufacturing too. It’s easy to quickly produce an enclosure prototype with modern 3D printers where you’ll have a fitting enclosure built within hours. However, it’s a mistake to assume that the enclosure built with a 3D printer can be easily reproduced in volume.

3D printing gives you the flexibility to produce any shapes and colors. You may not get such privileges in mass production, where the technology of choice is injection molding. Injection molding involves building the mold for the enclosure, which is then used to mass-produce the plastic parts.

Generally, injection molding is more restrictive in the shapes that it could produce. If you’re trying to produce highly complex shapes, you may not get the desired results, or you’ll need to pay a higher cost for the setups. So, it’s always wise to verify that the prototype enclosure is manufacturable.

Learn More About Prototype: How to Prototype New Electronic Hardware Product

 

5. PCB Is Too Complex For Cost-Effective Manufacturing

The market demands smaller electronic products. For hardware designers, it means squeezing tinier components into a compact PCB. PCB spaces become a luxury, and there’s barely to route the interconnecting traces.

Such circumstances forced designers to use advanced routing strategies, such as blind or buried vias on a multilayer PCB. A blind via connects two middle layers while buried vias connect an outer and a middle layer. Both are difficult to manufacture and result in higher costs.

If you’re designing a flex or rigid-flex PCB, you’ll need to understand the mechanical constraints of such circuits. For example, vias and pads should not be placed on the bending area. Avoid sharp corners on traces along the bend and use teardrops to strengthen trace-to-pad joints. Failing to adhere to the best practices will make the manufacturing process difficult, if not impossible.

 

Your Takeaway

Hardware designers would have their hands full when designing electronics products. There are just too many variables that could go wrong at the design stage. It’s easy to commit mistakes that will prove costly down the line. It helps to collaborate with reliable partners where the designers could offload non-design tasks and focus more on the design itself.

ICS has worked with many hardware designers in electronics component sourcing and connecting them with the best PCB manufacturers in Shenzhen.

 

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