Does H bridge driver require back-voltage protection?

Hi

Currently, im trying to use a h-bridge driver to power up my 12 VDC motor. However, after reading from several websites, I found that some h-bridge driver require back voltage protection.

Therefore, what i intend to use is a L298 h-bridge driver. Is back voltage protection required for this IC?

Thx for any advise!!!

fabbie said:

Hi

Currently, im trying to use a h-bridge driver to power up my 12 VDC motor. However, after reading from several websites, I found that some h-bridge driver require back voltage protection.

Therefore, what i intend to use is a L298 h-bridge driver. Is back voltage protection required for this IC?

Thx for any advise!!!

Click to expand...

I dont know about the driver you mentioned but it is in general a good idea to suppress over voltage conditions when running inductive loads like a motor. A usual method is using a zener diode across the bridge output if unidirectional and a series back-to-back zener if bi-directional. Also a zener or transorb on your +12 would be a good idea also. If you have access to an O-scope, take a look at all the hash & spikes the motor injects back into your circuit.

And if zeners are too cheap for you , MOV's and or Transorbs will also do the job nicely.

Yes, you need to add protection.

If you check the datasheet
https://www.electro-tech-online.com/custompdfs/2004/10/LM18298.pdf

page 6 - 'application information' you even see the diodes added in the example circuit.