AN14554

[Emisul]

Following up on the SmartFob power profile — two questions I couldn't resolve from AN14554.

The SmartFob configuration includes a motion sensor alongside BLE, UWB and the secure element. How is motion typically used in the power model? Specifically, does a production smart fob continue BLE advertising while stationary, or is advertising suppressed or slowed until motion is detected?

Second, does the estimator output an integrated standby current for a typical configuration? AN14554's advertising figures are measured at 100 ms, and I'm trying to understand the realistic 24/7 standby budget for coin-cell operation.

Thanks.

[sofiaurueta]

Hello, hope you are doing well.

I would recommend checking the "SmartFob BLE(KW47)+UWB(R5) Ranging - Power Consumption Estimator Tool v1.0" which is included under the Kinetis (KW3x/4x) Power Profile Tools for Automotive page.

This tool models the SmartFob power profile across four use cases and defines when BLE advertising is active versus suppressed.

In the "stationary" state (Use Case 1), there is no BLE advertising. The KW47 remains in Deep Sleep 2, while the motion sensor operates in standby mode. BLE advertising resumes after motion is detected, as mentioned for Use Cases 2 and 3.

For standby current information specific to the KW47 + UWB Ranger5 + motion sensor SmartFob configuration, refer to the Consumption Table at the top of the estimator worksheet. The table indicates a system level standby current of approximately 3.77 µA at a 3 V coin-cell supply, with the value broken down by subsystem as well.

Best regards,
Sofia.