Power consumption on the 9160DK board is higher than spec?

RE: Power consumption on the 9160DK board is higher than spec?

Charlie — Tue, 27 May 2025 14:09:26 GMT

Hi,

Please refer to the following reply:

all application RAM is retained.
all application RAM is retained, needs to use the RAM power API to turn off unused RAM.
Specified leakage is for ram retention. When powered down it does not consume any current.
network config and signal strength does not have an impact on PSM current.

Best regards,

Charlie

RE: Power consumption on the 9160DK board is higher than spec?

Trung Nguyen — Mon, 26 May 2025 04:22:16 GMT

Thank you for your response. I have a few follow-up questions related to RAM power consumption:

The Cellular UDP sample documentation does not clearly state whether RAM is retained during operation. Based on the context, I assume that RAM retention is enabled—could you please confirm?
I understand that the sample only uses a small portion of the available RAM. Is the entire RAM retained in this case, or only the regions that are actively used?
According to the Product Specification, the RAM leakage current is 100 nA per 32 KB block. Let’s consider three RAM states:
- ON (actively used when the CPU is running)
- Retained (while the CPU is idle)
- OFF (completely powered down)
I assume the specified leakage current applies to RAM blocks in the OFF state. Is that correct? Additionally, is there documentation available that specifies the current consumption for RAM blocks in the retained state?

And does the network configurations or signal strength have any affection on the device's power consumption while the LTE modem is in PSM mode?

Thanks again for your support.

RE: Power consumption on the 9160DK board is higher than spec?

Charlie — Wed, 21 May 2025 09:00:53 GMT

Hi,

Thanks for checking with us regarding your questions.

I double-checked the nRF9160 Product Specification, and it states that the voltage reference for power consumption is 3.7 V.

Current consumption @ 3.7 V:

Power saving mode (PSM) floor current: 2.7 µA

Please note that the PSM current listed is a typical value. Some variation is expected, so we recommend measuring multiple devices for a more accurate evaluation.

Best regards,

Charlie