As far as I know, the input pins to ICs are typically just the gate of a MOSFET. I have always just take stuff for granted (like if you want to control a logic pin, just put a source voltage on it), but recently I have been thinking about how these things actual connect.
How do I estimate the current level going through the signal line? For example,if I have a driver outputing a high frequency control signal to an IC, how do I estimate the instanteous or effective current going through this path so I can size my PCB trace appropiately? In my mind, the MOSFET will ask for as much current possible to charge and discharge the gate, so it could be pretty bad if the driver is capable of high current (1 A) but the trace is not sized properly. If the driver is limited, I don't think it is available in all IC datasheet so I want to understand what people do to ensure the signal trace is appropiately sized for power. I know some people will put a gate resistor to limit current and therefore transition time, but it is not the best to minimize FET power lost.
For signal lines, would the general design consideration is that you want to match impedance for signal integrity while making sure the trace can handle the required current?
Let me know if I am understanding it correctly!