AnsweredAssumed Answered

Question about ADAU1452 PCB layout

Question asked by IRON on Nov 6, 2016
Latest reply on Nov 9, 2016 by DaveThib

Hello all,

I have 2 questions on the figure below.

 

Question1

On the red box on the left side,

the 100nF cap is placed near to the GND not the PVDD as recommended on "Figure 81. Recommended Power Supply Bypass Capacitor Layout".

Is it okay?

 

Question2

On the red box on the bottom right, 1uF cap is newly appeared. 

what is this for??? Is this just a typo and you wanted to mean 10uF cap?

On page 178, there is even a description as below

 

"The 1 μF bypass capacitor is required to provide a local current supply for sudden spikes in current that occur at the beginning of each audio frame when the DSP core switches from idle mode to operating mode."

 

However, on page 176, you mentioned as below

 

"To provide a current reservoir in case of sudden current spikes, use a 10 μF capacitor for each named supply (DVDD, AVDD, PVDD, and IOVDD) as shown in Figure 83."

 

To prevent the current spikes, which cap should we need, 10uF or 1uF?

 

Best Regards,

Yuta M

Outcomes