I want to add a reverse-polarity diode to my design.
It has an input of 24 V (230 Vac to 24 V power supply) which is fed to a 24 to 12 V converter. I plan to draw up to 4 A from the 24 V power supply. The PCB works in a generally room temperature environment and has an SBC, mini pcie port and an RS-485 comm line.
I was planning on adding a diode with a serial fuse too, in parallel to the 24 V in order to prevent reverse-polarity connection damage.
I also want to add a surge protection to the same power terminal.
- Can I just use a TVS (bidirectional or unidirectional) instead of the diode?
- Do I need to have both?
- I know that a TVS adds a substantial amount of input capacitance. Should I be worried about it?
- Do I need to have other things in mind, when designing the circuit?