Hi all,
Recently, I am working on CC2564 and investigate the power consumption, When I observed the waveform of CC2564 under different states such as advertising, connnection, page scan, inquiry scan and so on, a waveform out of our exception happened.
In the following , we measure the waveform using the MSP-EXP430F5438 experiment board as Host and CC2564MODNEM Evaluation Board as controller, running the SPPLEDemo provided by TI Official.
Take the connection event waveform as an example.
I can't find any spec giving the standard waveform of CC2564, but I found a document instruting us how to measure the power consumption of CC2540/41, in which the waveform under connection event of LE mode is given as:
But when we measure the waveform of CC2564, the waveform of connection event is shown as:
in our test, connection interval =100ms. we can see that before every connection event (the higher spike in the figure), there will be a ~5mA current for ~35ms.
Refered to the BT 4.0 spec, a BLE device is transmitting only for a very small percentage of the total time that the device is connected. Therefore , the ~5mA current which sustaining about 35mA will significantly increase the current consumption.
In addition, we observed that when CC2564 is in advertising state(LE mode), page Scan state(Classic mode), inquiry scan state(Classic mode), Sniff state(Classic mode), the same current draw will exist, still 5mA, and will sustain for 35ms.
In the following, The waveform of advertising state(LE mode), page Scan state(Classic mode), inquiry scan state(Classic mode) are shown respectively.
LE mode, advertise, advertise interval = 100ms.
Classic mode, page Scan, page Scan interval =100ms, Scan window= 25ms
Classic mode, inquiry scan, inquiry scan interval =100ms, Scan window =12.5ms
Classic mode, Sniff mode, interval=500ms
As we stated above, we find that the 5mA current which sustain for 35ms will exist before every periodic event.
But we can't find any related configuration in the code.
So, my question is :
1 Is our waveform correct? if not, can you give me the standard waveform under each state?
2 If our waveform is correct, what's the origin of the waveform? Is it necessary? Can it be disabled? (If the 5mA for 35ms waveform can disappear, we can lower our power consumption significantly )
3 Any one can provide some document which can instruct us to measure the power consumption of CC2564?
Please help me solve this problem and thank you in advance !
Zhiyuan
