My working desk is constantly in a mess. It takes minutes to hunt for a missing pen and it’s not surprising to find my mug buried under a mountain of documents. Definitely not the best example for someone who’s tasked to be neat and meticulous in PCB design.
Thankfully, the exact opposite is true when it comes to my design process. I’m a bit of a stickler for documentation and I’ll ensure that each of the components are placed where they belong before I start routing any traces. With that said, I’ve come across my share of awkwardly designed PCBs (and, usually, the grumbles of technicians right behind trying to install them).
The technicians seem like the least of your problems, though, if you have improper component placement that’s affecting the functionality of the PCB. Through the optimization of electronic component placement, you’ll rest easy knowing your design will function exactly as intended.
How do you Achieve the Optimization of Electronic Component Placement?
If you’re starting fresh in your design process, you’ll have just finished your schematic transfer into PCB layout. Rather than placing the components at your whims, there are certain aspects to be considered.
Electronics component placement optimization is a process where the components are arranged in a manner of observing all the major considerations of functionality, fabrication, assembly, service, maintenance and cost.
Whether it is understanding that certain areas of the device will be under higher levels of duress, and thus require more careful attention on their component interactions or trying to finagle a high component density in a tight circuit board form factor, you’ll be sure to run into most of these factors, perhaps even at the same time.
Why It’s Important To Optimize Electronics Component Placement
You’ll want to consider noise coupling and heat dissipation issues when placing the components. Failing to observe these means you’ll have functionality issues when the PCB is produced. For instance, not separating analog and digital high-speed components is bound to introduce noise from one to another.
Optimized components placement increases serviceability.
If you’re producing enclosed consumer products, you have little to worry about maintenance and support. But if you’re working on industrial or commercial electronics, you’ll want to consider serviceability, because the harsh truth is, clients may prefer competitor products simply because it’s easier to service.
Consideration must also be given to the PCB assembly process. Sometimes, there may be some issues with assembly when some basic practices are not obeyed during component placement. For example, if you’re not aligning ICs with the same orientation, be prepared to get into trouble with the PCB assembler.
How to Optimize Electronics Components Placement on a PCB
To ensure your own design success, prior to design finalization, you might want to run through the following items as a checklist for your own component placement process.
1. Module Compartmentalization
When you have a complex design, you’ll want to keep analog, digital, audio and power components apart. The components have to be grouped and confined to a specific area in the PCB. This helps to minimize noise from cross-coupling between the parts. Of course, you’ll need to keep the ground separated and connected with a single point to ensure signal integrity.
2. Place Connectors at the Edge
If you’re designing a PCB that uses wire-to-board connectors and requires the technician to insert the cable manually, you’ll want to have them at the edge of the PCB. It makes the technician’s job easier and reduces the risk of damaging surrounding components.
3. Place Components on Only One Layer (if possible)
It’s understandable that PCBs are getting smaller and space is an expensive commodity. But if that’s not the case, you’ll want to place all the components on a single layer. It reduces the time spent on placing the components and thus, the cost of assembly.
4. Don’t Overcrowd the PCB
You have physical constraints to adhere to. But that doesn’t mean squeezing all the components to the point where there are hardly gaps is a good idea. Consider leaving some spaces for the traces to pass through.
Leave some space for traces to pass through.
5. Ensure Components Edge Clearance
It’s wise to keep small and fragile components from the edge of the PCB. The assembly process requires the PCB to be fabricated with a dummy strip for support. When all the components are assembled, the dummy strip will be detached and may damage SMD components placed along the edge.
Getting component placement right on a PCB may seem overwhelming but it doesn’t have to be when you’re using the right PCB tool. The interactive component placement on Cadence OrCAD will drastically reduce the time in doing so.
If you’re looking to learn more about how Cadence has the solution for you, talk to us and our team of experts.