hai,I am building a extension box in which we can plug in smart phone charger and when charge become 100 % this extension box cut the power to the charger .

1. I can design an app which run on android which produce a specific tone or sound pattern when battery become full , the extension box should recognize this sound pattern and turn the power off .

2. the circuit should be simple like ... the extension board should recognize to the specific sound pattern instead of voice recognition and other stuff ... sound pattern example : Beep-- second delay-- another Beep sound or any other combination or frequency

I have spend a lot of time on this project , please suggest a way making such a circuit ( I intentional avoided Bluetooth ,wifi etc to notify battery status )

 

Recognising a sound pattern by analogue means is doable, but more complex circuitry would be involved than if using a MCU. How are your programming skills?
If you go the analogue route, perhaps the MT8870 DTMF decoder IC would be useful.

 

This TS has another post on this subject. You might want to look at it to see what had been suggested.

I have an unpublished schematic that provides a digital solution. I didn't post it because of some missing information and @Bernard seemed to have a good solution.

http://forum.allaboutcircuits.com/t...-specific-sound-sequence.131775/#post-1089317

 

This TS has another post on this subject. You might want to look at it to see what had been suggested.

I have an unpublished schematic that provides a digital solution. I didn't post it because of some missing information and @Bernard seemed to have a good solution.

http://forum.allaboutcircuits.com/t...-specific-sound-sequence.131775/#post-1089317

Iam the one who created that other thread .. can u please post a schematics or block diagram ?

 

Recognising a sound pattern by analogue means is doable, but more complex circuitry would be involved than if using a MCU. How are your programming skills?
If you go the analogue route, perhaps the MT8870 DTMF decoder IC would be useful.

I have decent coding skills .. can u explain a bit more , please post a diagram if possible ?

 

Iam the one who created that other thread .. can u please post a schematics or block diagram ?

Let me resurrect the design. I'll get back yo you tomorrow.

 

I have decent coding skills .. can u explain a bit more , please post a diagram if possible ?

I've not used a DTMF IC so don't have a diagram. Try the datasheet, or Application Note if available.
As for the MCU approach, you could use an interrupt-on-change input pin to detect zero-crossings of a sound signal, then count zero-crossings in one or more given intervals to detect a pattern.