Flyback diodes for l298n

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Hello all,
I'm working on some project using l298n to drive two DC motors. I got to schematics using different arrange of flyback diodes( attached, marked 1 and 2 inside). Can I know which is the suitable one?

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Last Edited: Fri. Nov 29, 2019 - 05:01 PM
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Refer to the l298 datasheet!

#2 is electrically wrong methinks.

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#2 is wrong! In particular, the two diodes from motor terminals  to ground are backwards.

 

As far as snubber/flyback diodes, use them. While motors are mostly resistive in normal operation, if a motor has a high inertia load (e.g. flywheel or equivalent), the motor can generate a back EMF which can get quite high with that kind of drive. Also, there can be problems if the motor is stalled (then, it appears heavily inductive). Both situations can cause failures without the diodes.

 

Jim

 

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thank you for this explanation mister,

just for curiosity upon this question, if i used the l298 as for a fast stop do i still need the diodes ?

 

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If there is ANY chance that the motor can be stalled, then, YES, add the diodes.

 

Jim

 

Until Black Lives Matter, we do not have "All Lives Matter"!

 

 

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Forget the L298...it is rather pathetic, especially if you are operating at low voltage.

use something decent like, DRV8801  or  TB6612

 

What voltages/currents are you dealing with?

 

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