How do chip design engineers make sure that there is no interference between different circuit modules due to electromagnetic fields, given that every circuit component is very close to each other?
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There are several strategies used.
The first is modeling. The materials and characteristics are actually pretty well defined. You can apply models to calculate this. A little iteration can produce a chip module that has a lot of internal designed protections for all users.
A lot of this has actually already been done and is actually pretty well known. You will find the chip itself has these ‘distances’ already factored in based on its packaging and shielding. They also have comprehensive datasheets about it too for the devices most susceptible to this interference.
There is a lot of ‘reusing’ the old data here too. Reusing old layouts and geometries on new products.
The second methods are more of a strategy for operation.
Digital systems run on analog signals. The old TTL (transistor to Transistor Logic Level) is defined on a nominal 5V scale. It is literally a signal of up to 5V being sent. The standard said anything from 0V to 0.7V would be a logic low. Anything from 3.5V to 5V is logic high. The middle 0.7-3.5V is undefined.
This standard allowed a fair bit of ‘noise’ to be injected without impacting the data being sent. There are different logic standards out there.
In that same line of though, for data transmission between devices a ‘checksum’ can be included. This checksum is merely a quick mathematical operation on the data packet. it is calculated at the sender and receiver device. The receiver compares its calculation to what the sender did to see if data corruption occurred.
In the short, the electronics maker uses simulation and modeling, coupled with manufacturers specification and past use cases to do layouts. The manufacturers also employ different data transmission standards to allow and accommodate some level of interference that is bound to occur as well.
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