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Electronics => Beginners => Topic started by: VanillaIceCream on July 11, 2021, 10:35:35 am

Title: PWM Signal Generator in reverse polarity mode
Post by: VanillaIceCream on July 11, 2021, 10:35:35 am
Can I switch the output ports of this PWM motor driver module to get out a negative PWM signal for my motor without destroying anything in the module?
I found no info about it on the sellers page.


PWM Module:

https://www.amazon.com/dp/B07XR9B1RN/ref=cm_cr_arp_d_product_top?ie=UTF8&language=en_US (https://www.amazon.com/dp/B07XR9B1RN/ref=cm_cr_arp_d_product_top?ie=UTF8&language=en_US)
Title: Re: PWM Signal Generator in reverse polarity mode
Post by: Benta on July 11, 2021, 06:21:03 pm
I've no idea what you mean.
0...100% can be reversed to 100...0% PWM for a "negative pulse" PWM, if that's what you need.
Title: Re: PWM Signal Generator in reverse polarity mode
Post by: jpanhalt on July 11, 2021, 06:51:45 pm
In addition, it may depend on whether the motor case/frame is "ground."  In other words, motor ground and your PWM source share a ground.
Title: Re: PWM Signal Generator in reverse polarity mode
Post by: ledtester on July 11, 2021, 06:56:27 pm
Do you mean you want to create a PWM signal between 0 and -5V instead of between 0 and 5V?

Then you might try this which doesn't require a negative rail:

https://electronics.stackexchange.com/a/221425/95488

The output won't be able to provide a lot of current, but into a high impedance input it should work.


Title: Re: PWM Signal Generator in reverse polarity mode
Post by: VanillaIceCream on July 15, 2021, 03:59:15 pm
Do you mean you want to create a PWM signal between 0 and -5V instead of between 0 and 5V?

Then you might try this which doesn't require a negative rail:

https://electronics.stackexchange.com/a/221425/95488

The output won't be able to provide a lot of current, but into a high impedance input it should work.



Yes exactly, thanks.