AN92584 Datasheet, PDF (37/42 Pages) Ramtron International Corporation – Designing for Low Power and Estimating Battery Life for BLE Applications

Designing for Low Power and Estimating Battery Life for BLE Applications
F – After transmitting the three advertising packets, the BLESS generates an “end-of-event” interrupt that wakes up
the CPU. The BLE stack and application complete any event-specific or other application-specific activities in this
period. The application then programs the BLESS to enter the DEEPSLEEP mode by calling the
CyBle_EnterLPM()function in the BLE Component. The BLESS takes two LFCLK cycles (approximately 120 µs)
to switch to the WCO and enter the DEEPSLEEP mode internally. The BLE Component therefore puts the system
into the Sleep mode until the DEEPSLEEP mode entry is complete.
J – The system is in the Sleep mode in this state, waiting for the BLESS to enter the DEEPSLEEP mode. Once the
transition is complete, the BLESS generates an interrupt to indicate successful entry into the DEEPSLEEP mode,
which wakes up the CPU.
G – When the application receives the interrupt at the end of stage J, the application puts the system also into the
Deep-Sleep mode no processing is required.
Note: In the profile described, it is assumed that the application is only managing the BLE advertising events and not
handling any system-level tasks and interrupts. Additional system-level processing will change the current profile
depending on the implementation.
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Document No. 001-92584 Rev. *A
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