Substitute for 2450FM07A0035T on the nRF52832-CIAA

[mraj]

Hi,

  I'm designing a prototype board with the nRF52832-CIAA and was planning on using the Johanson 2450FM07A0035T integrated 2.4 GHz filter, but have not been able to find these parts in abundance.  I was curious if the following part could be used to match well to the nRF52832-CIAA and would be a drop-in replacement for the Johanson part: DEA102500LT-6307A1 (https://www.digikey.com/product-detail/en/tdk-corporation/DEA102500LT-6307A1/445-6877-1-ND/2649233).

  Thank you,

     Milan

[AmbystomaLabs]

The TDK is not impedance matched to the nRF52 so it cannot be used as a direct replacement.

Johanson makes the 2450FM07A0029T while matched for the QFAA and not the CIAA would probably make a sufficient drop in replacement and is in good supply at distributors. The QFN and WLCSP parts have similar, though not identical, matches. You should confirm harmonic suppression and output power on your design with it before committing to production.

Otherwise, you will have to add the lumped element match for the nRF to your design and switch to a 50ohm part like the TDK.

[AmbystomaLabs]

I suppose a third option is just to commit to a reel of 10,000 pieces and suffer through the lead time.  On chip parts there isn't a lot of tooling involved so Johanson could probably turn them for you in a reasonable amount of time.

[mraj]

Thanks for the reply.  Unfortunately I wouldn't need that many components at this point in development, so minimum orders of 10k won't work very well.  QFAA version might work well, thanks for the tip.