One of my colleagues claims that no matter what frequency the PCB board has, you cannot allow reflections inside the tracks. In this case, it's 1 Hz frequency that is going to turn a relay ON. The control signal to the relay is controlled by one AND-gate and followed by two OR-gates.
He claims that I need to study the reflection between the AND-gate and the OR-gates. He suggests that I should have a resistor between these two gates, to prevent reflections.
I said that it's no speed. And he said that it does not matter. What he said is the rise time that matters. If the rise time is to small, then the system won't work at all, no matter how "slow" the system is or what type of impedance the inputs have.
The relay is going to be turned on constantly, and sometimes the relay is going to act like PWM in 1 Hz.
Question:
What's the idea by having a serial termination between two different gates, if the PCB board is not high speed? According to him, the PCB would not even pass the test if I don't have some kind of termination that prevents reflections and he repeats that "High speed or low speed or 1 Hz...you need to compute the rise time and compute what type of serial resistor you should use to prevent reflections".
So now I'm confused. How can a well experienced engineer (masters degree) claim that? It must be something he has noticed that nobody else has noticed?
Like a pit fall?
Some further details added in comments (now chatroom) which may be relevant:
It's 50 mm between the gate inputs/outputs. [My colleague] claims that it could be reflections there.
There is a "clock" signal that comes from a 555 timer of 1 Hz. He claims that the output must have a serial resistor, if the rise time is to low. He claims that the input of the AND-gate might missunderstanding the input signal from the 555 timer. The distance between the 555 and AND is about 50 mm.
The AND gate is 74LVC1G386GW and the 555 timer is LM555CMMX/NOPB and the OR gate is MC74VHC1GT32DFT1G.