faithz
Newbie level 2

Need help! Automatic switch circuit to choose the cable impedance by using TDR.
I would like to design a TDR that has multi variable output to match the transmission line of copper cable with circuit. E.g. The TDR actually consist of 50, 75, 100, 150, and 300 Ω outputs. What circuit may I choose or any chip that existed?
The circuit also can be used to select input pulse width. The circuit I used just now is simply traditional switch or selector. I need to switch it automatically.
I would like to design a TDR that has multi variable output to match the transmission line of copper cable with circuit. E.g. The TDR actually consist of 50, 75, 100, 150, and 300 Ω outputs. What circuit may I choose or any chip that existed?
The circuit also can be used to select input pulse width. The circuit I used just now is simply traditional switch or selector. I need to switch it automatically.