Hi.
I am beginning in Electronics. First, I'd like to build an ultrasonic switch, that woult light a led when a button is pushed. I have done the circuit of the emitter. But i have some troubles using the US sensor...
Here are the datasheets I have found for my US sensor (I have the MA40B8R) :
http://www.datasheetcatalog.com/datasheets_pdf/M/A/4/0/MA40B8R.shtml
http://www.murata.com/catalog/p19e.pdf
Nonetheless, I have tried to draw a circuit of that ultrasonic receiver. I used this drawing, which is in the end of the datasheet :
http://lafavorite.forum.free.fr/forum/images/DataSheetCircuit.JPG
The problem is that I do not really understand that drawing (you also have to know that I am french, and so, I do not understand English so much. Sorry for the mistakes I have made...). And the battery is not represented in that circuit : that is why, as I am a beginner, I do not really know where to put it... I have drawn that circuit :
http://lafavorite.forum.free.fr/forum/images/Circuit4.JPG
I have understood that when it receives a 40 kHz signal, the US sensor produces a current that will be increased by the OP-AMP. I have chosen the LM 324. Do I have to choose another one? The opamp is in inverting mode : how should I put my led in that circuit? Should I turn my Led in the other side? In fact, I have understood that the receiver transmits a current only when it receives a 40kHz signal. Should I nevertheless filter that signal? Do I need that 47 nF capacitor?
Here :
G=-R4/R5
G=2.2mOhm/47kOhms
G=-46.8.
In fact, I have chosen a gain of about 50 because I would need a current between 3V and 6V to light my Led. But the problem is that I do not know the value of the current that will be produced when the sensor receives a signal. How could I find that value??
And finally, is that circuit right? Else, how should I link the sensor to my battery? Is 6 Volts enough??
Thanks for all.
I am beginning in Electronics. First, I'd like to build an ultrasonic switch, that woult light a led when a button is pushed. I have done the circuit of the emitter. But i have some troubles using the US sensor...
Here are the datasheets I have found for my US sensor (I have the MA40B8R) :
http://www.datasheetcatalog.com/datasheets_pdf/M/A/4/0/MA40B8R.shtml
http://www.murata.com/catalog/p19e.pdf
Nonetheless, I have tried to draw a circuit of that ultrasonic receiver. I used this drawing, which is in the end of the datasheet :
http://lafavorite.forum.free.fr/forum/images/DataSheetCircuit.JPG
The problem is that I do not really understand that drawing (you also have to know that I am french, and so, I do not understand English so much. Sorry for the mistakes I have made...). And the battery is not represented in that circuit : that is why, as I am a beginner, I do not really know where to put it... I have drawn that circuit :
http://lafavorite.forum.free.fr/forum/images/Circuit4.JPG
I have understood that when it receives a 40 kHz signal, the US sensor produces a current that will be increased by the OP-AMP. I have chosen the LM 324. Do I have to choose another one? The opamp is in inverting mode : how should I put my led in that circuit? Should I turn my Led in the other side? In fact, I have understood that the receiver transmits a current only when it receives a 40kHz signal. Should I nevertheless filter that signal? Do I need that 47 nF capacitor?
Here :
G=-R4/R5
G=2.2mOhm/47kOhms
G=-46.8.
In fact, I have chosen a gain of about 50 because I would need a current between 3V and 6V to light my Led. But the problem is that I do not know the value of the current that will be produced when the sensor receives a signal. How could I find that value??
And finally, is that circuit right? Else, how should I link the sensor to my battery? Is 6 Volts enough??
Thanks for all.