Suitable capacitance values for COMPA and COMPB

[Ryoma]

Hello expert,

We are designing a circuit using STWLC38.

What happens if the capacitance value of C8~C11 in the figure below is increased to 47n?

Will it be a problem?

Regards,

Ryoma

[willzhou]

Hi Ryoma

Increasing the COM capacitor will affect the modulation of ASK;
bigger is not always better, as this is related to the system.
Additionally, the voltage AMR amplitude of STWLC38 VRECT has limitations.
If the ASK signal is too high, it can easily cause chip damage.

[Ryoma]

Hi Willzhou, 

Thank you for your help with another Thread.

In the following thread you suggest increasing the capacitance values of COMPA and COMPB, why is that?

STWLC38JRM does not output 5V at VOUT pin - STMicroelectronics Community

I understand that too large a capacitance values can be a problem, but is 0.047 uF too large for C8~C11?

Are these values very severe?

Regards, 

Ryoma

[willzhou]

Hi Ryoma

Cap large do not mean ask mod also large. it depends on the sytems.

[CarsonReed]

Thank you so much for the information.