Capacitor and Inductor Footprints

[SwapnilMarathe]

Hi,

I see that in the nrf52810 reference layout (Nrf52810 Reference Layout), all the capacitors and inductor have 0402 or 0603 footprint.
i would like to switch the foot prints of cap/inductor to 0805 or 0603.
What will be the impact on the performance of the circuit and especially what will be the impact on RF part ??

[Andreas]

Hi,

 

For most components it should not make any mentionable difference, provided the layout is kept fairly similar. C3 and L1 should be avoided though, making them larger might inhibit replicating the reference layout, which in turn will alter the performance. Especially spurious rejection is quite prone to layout differences, and while it can be optimized by fine-tuning C3 and L1 values, the more your design deviates from the reference design, the more you increase the risk of having to trade off some output power in order to get the spurious emissions down.

 

Our recommendation is therefore always to replicate the reference design as closely as possible, and always measure RF TX characteristics and tune the matching network if needed.

 

Best regards,
Andreas