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I plan to use the L6472 step motor driver but I'm not sure if I should use flyback diodes connected to the driver output side.

The step motor will be bipolar with the following specs: enter image description here

The L6472 has internal source-drain diodes with these specs: enter image description here

Usually there are always flyback diodes but not on the evaluation boards of the L6472. So is it safe not to use these diodes? Or might the L6472 be damaged? The datasheet doesn't say more about the diodes...

Thanks!

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You don't need to add flyback diodes to an H-bridge because the source-drain diodes will perform that function, however if you parallel the internal source-drain diodes with external Schottky diodes, the chip will run cooler. The voltage drop of the internal diodes is relatively large.

enter image description here

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Indeed, nothing mentioned about flyback diodes in the datasheet. The application diagram also does not show them. Since the IC can supply motors with up to 7 A the output MOSFETs must be quite large and this means the source-drain (in reality source-bulk but the bulk and drain are shorted) will be quite large also.

I think it's safe to assume that you don't need to place flyback diodes.

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After seeing the datasheet of the L6472 component, i assume you don't have to use the flyback diodes, since the component is protected by a overcurrent detection see §6.9, which can turnoff the MOSFETs in case of overcurrent. But you can place the flyback diodes (shotky diodes for exemple) at the outputs to add another level of protection to your circuit. For the diodes in your table are the diodes of the MOSFETS
MOSFET Diode

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