IFX007T Max PWM Frequency

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
User17663
Level 1
Level 1
First solution authored
Hi,

I am looking at using the IFX007 [1] in a BLDC driver setup, the PWM frequency
that the controller generates is about 100kHz. have been looking at what max PWM frequency
the IFX007 supports.

The documents at some place states eg: 20kHz, somewhere else states 25kHz and elsewhere
30kHz. I am unable to find a location where it states the absolute maximum for the device.

Can someone clarify, please ?

[1] https://www.infineon.com/cms/en/product/power/motor-control-ics/intelligent-motor-control-ics/single...

Thanks,
Manu
0 Likes
1 Solution
User17663
Level 1
Level 1
First solution authored
Hi Srivatsa,

Thanks for the details. Much appreciated. Will try the device.

Best Regards,
Manu

View solution in original post

0 Likes
2 Replies
Srivatsa
Moderator
Moderator
Moderator
First comment on blog 10 sign-ins First like received
Hi,

As per page 22 of device datasheet, for the selection of the max. PWM frequency the chosen rise/fall-time and the requirements on the duty cycle have to be taken into account. We recommend a PWM-period at least 10 times the rise-time.
Example:
Rise-time = fall-time = 0.22 µs as per the min. specifications in table 7 of device datasheet.
=> T-PWM = 10 * 0.22 µs = 2.2 µs.
=> f-PWM_max = 450 kHz.

This is a theoretical value. It must be verified in real application. Power dissipation limits of the device should also be considered.

For your switching frequency of 100 kHz, if we back-calculate as per above, rise-time+fall-time = 1 us, which is well within the device specifications.
0 Likes
User17663
Level 1
Level 1
First solution authored
Hi Srivatsa,

Thanks for the details. Much appreciated. Will try the device.

Best Regards,
Manu
0 Likes