For the L6235Q: What is the maximum PWM frequency for the FWD/REV pin or EN pin if I wish to use them for motor control?

[JMure.1]

I would like to use a PWM to control motor speed in our particular design (like what is described in DT0001), but I could not find in the datasheet where a maximum PWM frequency, minimum high time, and minimum low time are specified for EN or FWD/REV. What is the maximum PWM frequency to the FWD/REV pin on the L6235Q for using a PWM to drive speed and direction per DT0001? For EN, it seems it must be longer than TD(off)EN + TD(on)EN times...

[Cristiana SCARAMEL]

Hello @JMure.1​ and welcome to the ST Community.

Considering the target of not having distortion of the output signals compared to the input PWMs, I would advise not to exceed a few tens of kHz (take into account that the contribution of the dead time is about 1 us for each commutation to which the other timing are added).

Let me know if these info are useful to you, if yes please "Select as Best" label to close the topic.

[JMure.1]

Cristiana,

Thank you for you're reply. When you write "a few tens of kHz", is that up to 20kHz or 30kHz? Can you give me a harder number for which the PWM frequency is definitely safe?

Regards,

John

[Cristiana SCARAMEL · Accepted solution]

Hi @JMure.1​,

both 20 or 30 kHz are safe, depends on the resolution you want to achieve with your control.