AN92584 Datasheet, PDF (34/42 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
6 Appendix A: Advertising State Current Profile
The PSoC 4/PRoC BLE device in the advertising state transmits packets containing the advertising data in periodic
events. Three advertising packets may be sent in an advertising event (one on each of the three enabled advertising
channels). The device may optionally listen for and respond to a peer BLE device that receives the advertising
packets and requests for additional data.
The time between the start of the two consecutive advertising events (T_adv_event) is specified as follows:
T_adv_event = advInterval + advDelay
The advInterval is an integer multiple of 0.625 ms and has different ranges for different advertising packet types. It is
typically chosen in the range 100 ms to 10.24 s. The advDelay is a pseudo-random value with a range of 0 ms to 10
ms. Advertising events are illustrated in Figure 20, with one advertising event as an example.
Figure 20. Advertising Event and Interval
ADV_IND
Channel 37
ADV_IND
SCAN_REQ SCAN_RSP
Channel 38
Channel 38
Channel 38
T_IFS*
T_IFS
ADV_IND
Channel 39
Advertising
Event
Advertising
Event
Advertising
Event
T_advEvent
T_advEvent
advInterval
advInterval
advDelay
advDelay
* T_IFS is Inter Frame Space, which is defined to be 150 µs. This is to allow the radio to switch between transmit and receive states.
6.1.1
Current Profile
The advertising state current profile for a PSoC 4/PRoC BLE Peripheral device implementing the recommendations
for low power is shown in Figure 21. It illustrates the power mode transitions, along with the BLE state transitions and
relative current levels across the states.
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Document No. 001-92584 Rev. *A
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