Piezo Ultrasonic transducer driver

[brimsant]

Hi guys

Can someone take a look at this schematic and see if there are any glaring issues with it? I'm pretty new to circuit design so most of what I have is from looking at the designs of other people.

Basically what I want to do is to program the PIC to read the temperature from the Thermistor and then driving a piezo ultrasonic transducer through Frequency Shift Keying to send the reading.

I am planning on using this transducer: https://abra-electronics.com/sensor...sor-16mm-1-pair-transmitter-and-receiver.html

 

[Lightium]

Your thermistor is using the wrong pin.

 

[brimsant]

Your thermistor is using the wrong pin.

Hi, Which pin is the correct one?

 

[JimB]

Your thermistor is using the wrong pin.

According to the PIC Datasheet, pin 11 (RA2) is configurable as an analog input.
Looks like a reasonable choice to me.

So why is it the wrong pin?

JimB

 

[Nigel Goodwin]

Yes, RA2 looks fine - but another point, why use a crystal?, the PIC has a perfectly satisfactory internal oscillator which is accurate enough for driving a piezo.

However, I'm a bit puzzled about the use of the piezo transducers?, it seems a pretty strange and unreliable method of communication?, and requires fairly precise alignment.

 

[Lightium]

"Is configurable" I stand corrected. I would think the OP would want AN0 for analog measurment.

 

[Nigel Goodwin]

"Is configurable" I stand corrected. I would think the OP would want AN0 for analog measurment.

Why? - AN0 is no different to any of the other analogue inputs, and requires exactly the same configuration to be used.