Taking Another Look At ISO 13485
ISO 13485 is about potential risks involved and mitigating them during and after the building of medical products. It is a specific ISO standard serving as a comprehensive management system for the design and manufacture of medical devices.
Like other ISO standards, its focus is on continuous improvement in process and quality systems. Also, a main emphasis is placed on cleanliness procedures clearly listed as a medical product undergoes various development and production stages, as well as tracking the lots as they get built over time.
A number of critical factors must be taken into account at PCB design layout stage. The most prominent are checks and balances during the layout phase, component selection and cross referencing when needed, complete fabrication and assembly drawings, and test coverage on the board for either ICT or flying probe testing.
Find out more by checking out our article on this important aspect of medical electronics products.
In the meantime, here are some tips and hints to get a good handle on PCB design and manufacturing when it comes to complying with ISO 13485.
- Proper splitting of power and ground planes, as shown in Fig. 1, is vital to reduce noise and crosstalk.
- High or relatively high signal-to-noise ratios (SNR) are undesirable in medical electronics designs. SNR can adversely affect signals, preventing correct medical device readings and subsequent patient diagnosis.
- It’s best to use ample ground layers as needed. Those layers help to suppress noise and keep SNR in check to a desirable level.
- It’s a good idea for the experienced PCB designer to collaborate with OEM designers to review the BOM and assure they’re using components with the correct level of tolerances, and their availability is not an issue.
- When it comes to the design-for-test (DFT) of a medical electronics design, the savvy PCB designer ensures an ample amount of test points are assigned for a board to ensure DFT, as well as for adequate test coverage.
- The prudent OEM works together with its EMS provider or to define a battery of tests to make a medical PCB foolproof and safe in the field.
Also, ISO 13485 requires a large amount of traceability in terms of medical products. PCBs must be serialized and allocated in terms of batches. This means these products being build can be traced in the lot codes and batch codes. Further emphasis is placed on component traceability. If a component or set of components encounter a problem or slightest issue at assembly stages or even in the field, then there must exist a formal, well-documented paper trail leading back to suppliers and manufacturers associated with those component lots should be in place.