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F7x2 vcap1 - looking for compatible capacitor

RBoer
Associate II

According to AN4661 "Getting started with STM32F7 Series MCU hardware development ":

"When the voltage regulator is enabled, VCAP1 and VCAP2 pins must be connected to 2*2.2 μF low ESR < 2 Ω ceramic capacitor. In the STM32F7x2Rx devices, only the VCAP1 pin is available and must be connected to 4.7 µF low ESR between 0.1 Ω and 0.2 Ω ceramic capacitor."

To try and figure out a compatible capacitor, I looked up the BOM from some nucleo boards, and they list the 2.2 uF capacitor - but none of the BOM's list the variation using a 4.7 uF capacitor.

So looking through datasheets of capacitors and trying to understand it, I found several (quite similar) ones, for example this one.

0690X00000A9ovFQAR.png

So how do I figure out if it meets the requirement? Obviously it's not in the 0.1-0.2R (=red box) range over the entire frequency... Should I only look at the frequency of my HSE-oscillator (8Mhz = the green vertical line)? And should I then conclude this one is incompatible, because the blue graph isn't in the 0.1-0.2R range for exactly 8Mhz?

Anyone happens to know a capacitor which is compatible with the vcap1 of the F722 in 0603 package?

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