microvia on NRF52840-QIAA-R

[MOUGEL]

Hello, We have choose NRF52840-QIAA-R for our design, can you give me more infrmation on microvia use between layer 1 and layer 2 please?

What is drilling and pad dimension? microvia on ball is mandatory? can you use microvia between ball?

Thanks you in advance for your information

Best regards

Laetitia MOUGEL

[Simonr]

Hi

The microvia hole sizes are 5.906mil (0.15mm). The pad dimensions are 10.827mil*10.827mil (0.275mm*0.275mm). Can you please specify what you mean by "ball"? The microvias used in our PCB designs are mandatory to make room for tracks to all pads on the nRF52840 chip. 

Best regards,

Simon