UCC27524A-Q1: Capacitor of VDD PIN of UCC27524A-Q1

Masami Michino

Part Number: UCC27524A-Q1

Dear, All

Customers are using UCC27524A-Q1.
They are struggling with the supply difficulties of recent multilayer ceramic capacitors.
Therefore, we are investigating whether it is possible to reduce the capacitance of the device's VDD decoupling capacitor.
They connect the IGBTs to OUTA and OUTB of UCC27524A-Q1 via damping resistors. Its resistance is several hundred Ω.
As a result, they want to reduce the capacity from the specified 0.1μF of the decoupling capacitor for VDD, but can they reduce the capacity if their evaluation did not cause problems?
Or does it cause problems if it is less than 0.1μF?
Please tell me.

Thanks, Masami M.

over 5 years ago

0 Don Dapkus over 5 years ago

TI__Guru**** 189399 points

Hi Masami,

Gate driver ICs need to deliver extremely high peak currents in order to charge and discharge the gates of the power transistors. These high peak currents are supplied by the local decoupling capacitors.

I do not recommend trying to use a gate driver without them.

0 Masami Michino over 5 years ago in reply to Don Dapkus

Genius 5070 points

Hi, Don-san,

Thank you for your reply.

However, they do not use local decoupling capacitors.
For example, they are studying whether 0.1μF decoupling capacitors can be changed to 0.022μF.
If they do not have a problem with evaluation, is such a change possible?

Thanks, Masami M.

0 Don Dapkus over 5 years ago in reply to Masami Michino

TI__Guru**** 189399 points

Hi Masami,

We can't recommend that. If they decide it can work in their application, and do the engineering work necessary to prove it, then they can do it.

It may be okay, there are many factors, switching frequency, voltage, FET being driven, etc, etc.

Power management

Power management forum

UCC27524A-Q1: Capacitor of VDD PIN of UCC27524A-Q1