This PCB, like almost all of my PCBs, is a four-layer board. In my opinion, it is not wise to restrict yourself to two layers unless you’re dealing with a very simple circuit or you really need to cut costs. The four-layer arrangement is beneficial in terms of routing and performance: routing, because via connections to internal planes almost completely eliminate power and ground traces; and performance, because the internal planes allow for low-resistance, low-inductance power and ground connections. The extra top-layer and bottom-layer real estate opened up by all the internal-plane connections come in very handy when you need to provide a generous copper area for improved thermal performance (for example, to make sure that your LDO or your motor driver doesn’t overheat and enter thermal shutdown).
The datasheet goes on to say that "the nRESET pin is internally connected to VDD with a pull up resistor of 50 kΩ." So... why are there two options for how to configure the nReset pin when it is not being used? Why not just recommend that it should be left floating (since it is already pulled high internally)? And, if there are indeed technical reasons for when the pin should be externally pulled up to VDD (for better noise immunity, as an example) then let us know what those technical reasons are.
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