UCC24624: Questions

Hello,

Your inquiry is under evaluation and I will get back to you shortly.

Regards,

Hello,

Could you tell me what Vref and VDD capacitor values are?

Regards,

Hello,

Your inquiry is under review and I will get back to you shortly.

Regards,

Hello,

Theoretically this should work.  What is the total gate capacitance that the driver is driving?

It should be at least 1/10 the VDD capacitor.  If it is not every time you drive the FET the VDD capacitor will discharge.

Regards,

Mike O'-san

Thank you for your reply.

The gate capacitance of the FET is about 2,500pF per system, for a total of 5,000pF for both systems.

VDD is 1uF, so the customer believes that there will be plenty of margin.

Regards,

Kura

Hello,

Your inquiry is under  review and  I will get back to you shortly.

Regards,

Hello,

So the VCC capacitor, VREF capacitor are sized well enough to handle the gate drive voltage.

I would have them double check the VCC voltage during operation to make sure it is above the UVLO threshold during operation? 

I would suggest they probe Vds, Ids of one of the FETs; as well as, VCC and VREF.  This will give you an indication of why the driver is not working?

Regards,