Hi All,
I'm using the BF 518 EZ-Board. I'm in the proccess of designing my own
custom board and need advice:
My application is a real time low power application in which the dsp should be
'asleep' most of the time (in order to save battery power). I would
like it to be a waken by an external codec's trigger lets say acordding to
a level of gain (sound / noise).
is there a way of doing it other than polling the dsp? - this uses too much
power.
does anyone know a Codec that has the abilty to can create an interrupt if the
sound is lowder then some treshold?
Thanks,
Chagai
waking the BF from sleep/deep-sleep with an external trigger from CODEC
Started by ●October 10, 2010
Reply by ●October 11, 20102010-10-11
Howdy Chagai,
That's a tough problem. I know of MEMS devices that can do that for
acceleration or free fall. For sound you need some way of detecting
vibration, and then determine if the amplitude of that vibration is strong
enough. A codec would have to be on all the time - and that takes power.
You might think about attacking the problem from a different direction.
The energy harvesting folks use vibration as one source of energy. You
might look at the circuits used for that to generate an interrupt, then
turn on the dsp and codec when enough energy is actually present. That
way you can use a small amount of energy from the environment as a source,
and you can keep all your main circuits dead until you really need them.
Patience, persistence, truth,
Dr. mike
On Sun, 10 Oct 2010, chagai_e wrote:
> Hi All,
>
> I'm using the BF 518 EZ-Board. I'm in the proccess of designing my own custom board and need advice:
>
> My application is a real time low power application in which the dsp should be 'asleep' most of the time (in order to save battery power). I would like it to be a waken by an external codec's trigger lets say acordding to a level of gain (sound / noise).
>
> is there a way of doing it other than polling the dsp? - this uses too much power.
>
> does anyone know a Codec that has the abilty to can create an interrupt if the sound is lowder then some treshold?
>
> Thanks,
>
> Chagai
That's a tough problem. I know of MEMS devices that can do that for
acceleration or free fall. For sound you need some way of detecting
vibration, and then determine if the amplitude of that vibration is strong
enough. A codec would have to be on all the time - and that takes power.
You might think about attacking the problem from a different direction.
The energy harvesting folks use vibration as one source of energy. You
might look at the circuits used for that to generate an interrupt, then
turn on the dsp and codec when enough energy is actually present. That
way you can use a small amount of energy from the environment as a source,
and you can keep all your main circuits dead until you really need them.
Patience, persistence, truth,
Dr. mike
On Sun, 10 Oct 2010, chagai_e wrote:
> Hi All,
>
> I'm using the BF 518 EZ-Board. I'm in the proccess of designing my own custom board and need advice:
>
> My application is a real time low power application in which the dsp should be 'asleep' most of the time (in order to save battery power). I would like it to be a waken by an external codec's trigger lets say acordding to a level of gain (sound / noise).
>
> is there a way of doing it other than polling the dsp? - this uses too much power.
>
> does anyone know a Codec that has the abilty to can create an interrupt if the sound is lowder then some treshold?
>
> Thanks,
>
> Chagai
