Different Techniques Of Designing For Rework

1. Different Techniques Of Designing For Rework

2. The term “circuit board rework process” is commonly used to describe any additional steps taken after the initial printed circuit board assembly processes have been finished. Even though it is obvious that reworks are nearly always essential during prototyping, many designers of PCBs don’t give thought to how their design choices can affect the future rework of products. The fact that a substantial amount of potential rework can be cut down merely by adopting certain design practices should also be kept in mind. This article will explore several approaches to designing for rework, all of which will ultimately streamline your work processes. Let’s take a look at how we may redesign your circuit board such that it’s not just possible to modify, but also easy to do so. Increase The SizeOf Your PCB Make the prototype larger than necessary because it is rarely as small as the final design. Because of the reduced need for intricate and intrinsic labor, the design may be released sooner, and a larger PCB is considerably simpler to modify. A larger PCB size provides for more PCB test points if space is available in the design. When using an oscilloscope or voltmeter to inspect your designs, you’ll need to insert test probes into PCB test points. Time and money can be saved because of the test points’ simplified error detection. It also has a slimmer design than conventional components, much like SMT parts. Test methods, such as J-TAG,should be considered in addition to PCB test points in such cases.

3. Increase the Size of Individual Parts In spite of how appealing micro BGA and QFN components may be, you can forego using them on your prototype. Note that reworking components smaller than a granule of sugar is a very labor- intensive task. For the same reason, exposed-lead ICs are recommended over BGA or QFN packagingwherever possible. Ensure Adequate Space Is Left For Parts The proximity of components, or the fact that some components are obscured by others, can make reworking more difficult than it has to be. When there is more space between parts, maintenance is simplified. Determine, given the available space, how an operator can get to the part to be swapped out. When working with BGA, QFN, or other packages that don’t have exposed leads, extra room between circuits will make localized rework much easier. If you’re doing any kind of rework that requires reflow heating, remember that any time you apply heat, it can harm nearby components, so more space is always better. Components close by can also be warped by the soldering iron’s heat. There will inevitably be additional labor to do because of this collateral damage. There are still more important design limitations to consider despite all this clearance. To maintain the purity of the signals, it may be necessary to pack the components close together.

4. Give Some Room For Tools Even if components are spaced out properly, soldering irons and other tools need easy access to all of them. The rework of a circuit board can be impeded, for instance, if a tall tantalum capacitor is positioned next to a small passive component with a footprint of 0603, making it impossible to reach the component with a soldering iron. It’s not just the parts that have to fit snugly together. Equipment that leverages against the PCB, such as those used for high-density or even press-fit connectors, require clearance. Tools like pliers, which require more space, may necessitate even more space. Keep this in mind as you work on the design. Alternatives for Resistors and Jumpers in the Strap Layout You can easily adjust the height of your setting pins during rework by using strapping resistors, which can be built into your design. You may also include a number of other alternatives in your prototype by doing things like adding extra filter circuits around your power regulators. If you wanted, you could even build a secondary circuit that could be realized by connecting two headers together with a jumper. Utilize Definable Components

5. Using programmable parts gives you some leeway in terms of redesigns, since you may make changes to your designs without endangering your hardware and the relatively low cost of programmableparts. The process of making significant modifications to programmable components is sometimes reduced to only modifying the firmware, rather than requiring more laborious measures like cutting traces or Desoldering. Compile and Place All Required Headers Many PCB engineers feel bad about passing up this opportunity. Yet many designers have paid the price for ignoring this in perspective. Don’t skimp now to save money later; your future self will thank you for installing every available programming header. Substitute Components It’s never ideal to have to do rework, but having the necessary spare parts on hand can make the job go much more smoothly and quickly if you ever find yourself in that position.

6. SOURCE URL https://dailytaker.com/different-techniques-of-designing-for- rework/