Issue link: https://resources.mouser.com/i/1442796
One can easily identify if their system compliance requirements can be covered by the standards listed in the PortNote Solution. If they aren't, we invite you to check with a local Bourns field team member or customer support line for further clarification. Next, study the recommended protection solution (Box 4). This diagram (also shown in Figure 2) forms the backbone of this PortNote Solution to achieve surge protection for RS-485 at the compliance levels listed in Box 2. The Bourns engineering team that develops PortNote Solutions for a given interface or power system has many years of hands-on experience, helping customers design their individual protection solution to meet or exceed their target protection requirements. If any problem is discovered or a customer has a question during the review or implementation of a protection design, as shown in a PortNote Solution, our field and factory teams are ready to help resolve them. One final, yet important point about a PortNote solution—it is not optimized. The goal is to make sure that our customers start with a solution that meets or exceeds their compliance test requirements. If there is concern on protection cost or board space constraints like in USB or SATA ports, further testing may be needed with other equivalent components. As an example, in the RS-485 port protection, Bourns TBU ® High-Speed Protectors (HSPs) provide excellent current limiting during surge events. However, TBU HSPs are active components, and typically, will occupy more board space than a passive component such as a power resistor. In some cases, a power resistor may be a more cost-effective option and a smaller substitute if surge levels are less severe. It's all about making the right "trade-offs" for a given application, and we leave this to our customers. However, we do make some alternate recommendations that are shown in Box 3. SUMMARY Procrastinating on a port protection design will no doubt continue given the complexity of today's highly integrated applications. To help streamline the task, Bourns has a growing resource library of PortNote Solutions that can really help expedite this often last, but important part of the design process. Please check out our current PortNote Solutions library. If you have request for a protection scheme that is not covered in this list, please do not hesitate to let us know. | 11 | Figure 2 Figure 1