STM32WB09KE VCAP Pin

[SebastianB]

Hi everyone,

we are currently in the design phase with a STM32WB09KE Controller.

Since we are designing the Power pins we have a question regarding the MLDO Vcap Pin.

On the Nucleo Board there is a Cap placed with a value of 0.22uF where does this value come from?

We can't find any information regarding this pin and which value we have to connect here.

If you have more information for us that would be good.

Thanks in advance Sebastian

[AScha.3]

Hi,

VCAP is the decouüling pin for the core supply.

So just do same, as in Nucleo Board :

The cap should be close to chip and ground plane . (and "good" MLCC, cer.cap , X7R , 25V or so.)

[SebastianB]

@AScha.3  Thanks for your fast response.

On the Nucleo Board they Use this one: https://www.mouser.ch/ProductDetail/YAGEO/CC0402KRX5R5BB224?qs=AgBp2OyFlx%2F0PlfJ7GyIIA%3D%3D&srsltid=AfmBOoq6EDQ8vt6eePuIMra2LUFYyEmmeiAb8BnOTGcYPIevHpkxXDOA

Which is a X5R 6.3V..

This is why Iam asking for more detailed information which Cap we could potentially use.

[STTwo-32]

Hello @SebastianB 

The best way is to use the Same Capacitor as mentioned on the Bill of material. But if you need to change, I think you should contact a HW expert to validate your choice.

Best Regards.

STTwo-32