Can capacities be optimized in i.MX8M Mini hardware design?

[jimmyli]

Hi,

     We are now developing i.MX8M Mini, and have some questions about capacities used for power filterring. .

     ----Question

     1>Can 0201 be replaced by 0402 package ? 

     2>As 0402 package is larger than 0201, the space for capacities is not enough.

         So, can the capacities be optimized to reduce the number? 

         Eg. 0.22uF*5 + 4.7uF*1  chang to  0.47uF*2+5.1uF*1

    Thanks.

--part of the i.mx8mm checklist

[mrudang_shelat]

Hi @jimmyli ,

The 0201 or 0402 decoupling and 0603 or larger bulk capacitors should be mounted as close as possible to the power vias. The distance should be less than 50 mils. Additional bulk capacitors can be placed near the edge of the BGA via array. Placing the decoupling capacitors close to the power balls is critical to minimize inductance and ensure high-speed transient current required by the processor. See the i.MX 8M Mini EVK layouts for examples of the desired decoupling capacitor placement.

You can reduce the no. of capacitor with higher value but make sure the capacitance value should be match as per recommended and place the capacitor near to pad / bulk capacitor near the edge of the BGA via array. Make sure the capacitance voltage is 3x of operating voltage rail. For more information for decoupling capacitor kindly refer HDG of i.MX8M (IMX8MMHDG).

Regards,

Mrudang

[jimmyli]

Hi Mrudang,

      Thanks for your reply.

[Rita_Wang]

Hi Jimmy,

For your questions:

1>Can 0201 be replaced by 0402 package ?

A: Yes, you can change the package to 0402.

2>As 0402 package is larger than 0201, the space for capacities is not enough.

So, can the capacities be optimized to reduce the number?

A: Firstly do not recommend to change the capacities and reduce the number too much. Otherwise, it will caused the power can not work steady.

So for power section it's better to follow the reference design.

Have an nice day

Best Regards

Rita

[jimmyli]

Hi Rita,

      Thanks for your rely.