Can I use different package inductor in impedance matching circuit of NRF52832 design

RE: Can I use different package inductor in impedance matching circuit of NRF52832 design

Jørn — Mon, 06 Nov 2017 12:05:32 GMT

As AmbystomaLabs stated the parasitic impedances are dependent on the component package size. Going for a smaller package typically has less impact as the component will behave a bit more like an ideal component (smaller dimensions compared to wavelength). However to be safe you should do measurements to ensure you still have a good match after changing component sizes.

RE: Can I use different package inductor in impedance matching circuit of NRF52832 design

Sweety — Mon, 06 Nov 2017 03:58:41 GMT

I am following the reference design only. Using smaller package than recommended should be fine(0201 instead of 0402) without doing re-match. Is it so?

RE: Can I use different package inductor in impedance matching circuit of NRF52832 design

AmbystomaLabs — Sun, 05 Nov 2017 16:22:24 GMT

Generally the short answer is "No." The package sizes are generally chosen to match the width of the microstrips or the design has been optimized for a particular package size. To do other than that results is large amounts of parasitic impedance associated with the part placement. This would leave the designer less than certain of the actual effect in the circuit a component may have.

So, assuming you are following the reference design verbatim and having copied the strip geometry across faithfully then, no you should not change the package size.

If you have not copied it faithfully and intend to use different size parts then you will need to re-match the circuit on your design.

If you are really determined to do this then you can probably go smaller to an 0201 but going larger to an 0603 would be a bad idea and would require re-matching.