External enable for NRF9160 boost converter

RE: External enable for NRF9160 boost converter

jeremyherbert — Wed, 12 May 2021 00:02:55 GMT

It's happening! github.com/.../e975f562f601c903f4e6e4f708dd67e9b47eee4f

RE: External enable for NRF9160 boost converter

jk1 — Wed, 21 Apr 2021 10:12:40 GMT

Came here looking for this exact question. Anything change in the last year or on the new silicon? Are there any tricks to allow a lower voltage, or rather put the boost in pass-through mode while asleep, or will the system still die at e.g. 2.8V in sleep/PSM? Unfortunately an e.g. 5uA sleep hit for 500mA boost sort of kills any low power prospects and just raises price to need lower Iq options.

Alternately, is there any reasonable option to completely kill power to the nrf9160 while in PSM sleep mode, or will the cold boot be a significant hit over warm PSM-wake-up boots?

RE: External enable for NRF9160 boost converter

jeremyherbert — Thu, 23 Apr 2020 11:06:28 GMT

Thanks. It would be good if you could perhaps consider this for the future in the modem firmware, much like how the COEX0 pin can be switched between LTE and GPS by an AT command. Even just knowing whether the modem is in sleep or not on an external pin would be very useful.

Right now my device wastes >80% of the standby current on the boost converter Iq and efficiency loss.

RE: External enable for NRF9160 boost converter

ketiljo — Thu, 23 Apr 2020 10:43:54 GMT

No, that's not possible. The DCDC converters are controlled partly by HW and partly by the modem. Changes here will require custom modem FW. In any case, the power hungry part, the PA, is powered by a separate DCDC converter and completely disabled when the TX is is not active.