I want to use the following dual diode for the return path with a fuse.

The diode is dual with each diode rated 25A, the cathode is the same, which means I have to connect it like in the figure? Do I have to add something more?


The purpose is to protect a motor controller as explained in this datasheet, pp 10.


simulate this circuit – Schematic created using CircuitLab

  • 2
    \$\begingroup\$ Putting two diodes in parallel is not normally recommended, though it won't hurt anything here; just know that almost all the current is going to go through one of the two diodes and make sure it's rated for that. You could just connect one of the diodes and leave the other pin floating, if you prefer, or use it for some other purpose. \$\endgroup\$
    – Hearth
    Apr 23, 2019 at 14:34
  • \$\begingroup\$ What are you trying to accomplish here? Is the fuse intended be in parallel with the diodes? \$\endgroup\$ Apr 23, 2019 at 14:38
  • \$\begingroup\$ Yes, I want to put a safety circuit for my motor controller, the vendor says you have to put a fuse in parallel with a diode, but I cannot find a diode that covers the requirements. 12V and 40A. I updated the question with the info. \$\endgroup\$
    – Luis
    Apr 23, 2019 at 14:45
  • 4
    \$\begingroup\$ The diode is not there to handle the 40A supply current from the battery (it's reverse biased so it won't conduct). It's there to handle regenerated current from the motors in the event that the fuse blows. So how do you calculate that as 40A? \$\endgroup\$
    – Finbarr
    Apr 23, 2019 at 15:09
  • 1
    \$\begingroup\$ Diodes will normally handle peak currents of 10 times their rated continuous forward current with no problem. I'm sure you can find a single diode that will do the job. \$\endgroup\$
    – Finbarr
    Apr 23, 2019 at 16:22


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