I have a 12V or 24V input system, the MPS buck converter has an EN-Pin max. Rating of 6V, how can I use it?
Answer: EN pin has typical an internal clamp Diode, like a 6.5V Zener-diode. With an EN-Pull-up resistor to Vin, that limits the current into the pin to < 150uA, the Buck converter will start-up when Vin is applied.
The calculation rule for the EN-Pin Pull-Up resistor is: R_EN > (Vin,max – 6.5V)/150uA
Be careful however that a few products don’t have this internal clamp: if it is not clearly stated in the electrical table or shown on the internal schematic, then the clamp is most likely not present. In that case you need to protect the pin externally with a zener diode, and add a series resistor (or a resistor divider) between Vin and EN.