AST-CAN485 I/O Shield only 24V?

It looks like the AST-CAN485 I/O Shield buck converter will handle up to 42 volts. Is there some other reason for limiting the input voltage to 24V max? I would like to use it on a 24V battery based system with a nominal charging voltage of 28-29VDC. Will the 24V inputs also not Handle more than 24V?

thanks,

Austin

Hi Austin.

The allowable input voltage range is 7-16V, however 7-12V is recommended. Anything above 16 volts will definitely damage the board.

TS-Chris, the OP mentioned the AST-CAN485 I/O Shield, but based on your response, I think you’re referring to the AST-CAN485 Dev board.

You’re right mdancer, that one slipped by me. Thanks for the clarification!

Looking at the [schematic, there are other parts on the board other than the buck regulator that are going to limit your max input voltage and were parts designed for 24 volt operation.

We don’t recommend going over 24 volts, but anything over 35 is definitely going to cause problems since there’s a capacitor on the board that maxes out at 35 volts.](https://cdn.sparkfun.com/assets/d/8/a/1/b/AST-CAN485_IO_Shield.pdf)