Hi,
several times we recommended
not to use 12V signals. But you are free to do what you want.
I´d reduce the voltage level to decrease EMI. The same time I´d make the signal line low ohmic.
But the problem with single ended signals is, that the signal current needs a return path. In your case GND. The current causes a voltage drop on the GND line. But with high frequencies the GND line is high impedance and thus the voltage drop is high. Not to compare with a volage drop caused by DC current.
The voltage drop reduces signal integrity.
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The signals i want to transmit are data and permanent clock
You want to change more than one signal? How many?
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Bandwidth:
A square wave signal has overtones. A lot of overtones. And the frequency (in theory) is unlimited. Therefore a 2MHz signal may send out overtones above the 100MHz region.
This is called EMI. The radiated energy may harm electronic devices nearby. You are responsible to comply with EMI standards of your country.
The solution is to suppress the overtones at the transmitter side with low pass filters. But the signal is no square wave anymore. The more you suppress the overtones the signal becomes shaped like a sine.
Usually it´s no problem to use a schmitt trigger (or comparator) at the receiver side to generate a square wave from the sine.
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You talk about delay. If this is an issue you have to tell us the specifications.
You talk about duty cycle. If this is an issue you have to tell us the specifications.
Klaus