nrf9160 thermal resistance

RE: nrf9160 thermal resistance

Heidi — Tue, 09 Jun 2020 07:24:16 GMT

Hi!

Yes, for thermal resistance junction to ambient, 35 C/W is the correct value. They will be adding this value to the ATEX compliance table in the nRF9160 PS V2.0.

Best regards,

Heidi

RE: nrf9160 thermal resistance

GiulianoFranchetto — Tue, 09 Jun 2020 06:51:19 GMT

Hi Heidi!

Any news on that ticket?

Regards

RE: nrf9160 thermal resistance

GiulianoFranchetto — Wed, 03 Jun 2020 15:12:30 GMT

Hi!

The value the ATEX comitee is checking is the junction to ambiant thermal resistance.

As the new specification of the nRF9160 now has a ATEX compliance table, I think this value should be added too.

The thermal analysis of every component of a design is mandatory for "intrinsic safety" mode of the ATEX standard.

Once you have this value, could you please send it as an "official" PDF with nordic logo and everything, as we will need to provide this data to the examinator.

Regards

Giuliano

P.S: some more information. A fuse is added to limit the maximum current drawn by the nRF9160. The max current is 600mA (peaks not included). The max voltage of the nRF9160 in our design is 5V. Adding the safety coefficient of 1.7, we reach 0.6 * 5 * 1.7 = 5.1W. We need to check that the heat generated by the nRF9160 is below the ignition temperature of gazes present in ATEX areas.
Even if the nrf9160 shall never consummes 600mA constantly, the ATEX examinator will always check the worst "imagniary" case.

RE: nrf9160 thermal resistance

Heidi — Wed, 03 Jun 2020 14:47:25 GMT

Hi!

So, for thermal resistance data, I can't find much. The thermal conductivity of the SiP is 35 C/W.

If you need the junction to ambient thermal resistance number specifically, I can try to find that out for you, just let me know.

Best regards,

Heidi