Hi,

I'm developing a custom board based on your schematic for the DA14580 (E-DA14580A3DB-P_va_schematic_0.pdf) and I have a few questions about some of the components you used.

1) I could not find the specific 16 MHz crystal that you used available on the market (NX2520SA). Is there a comparable one you recommend that can be used in place of this?
2) I also could not find the 1uF low-ESL capacitors that you used. Are there other low-ESL capacitors available that you recommend in 0402 packaging? And do they need to be low-ESL capacitors?
3) Do you have any information about the antenna you used in the design? If not, do you know if there is a chip antenna available on the market that has comparable characteristics to the one you used?

Thanks!