First of all, forgive me if this has been asked 20K times before. Since I have only the basic electronics knowledge (passive components, simple circuits, Ohm's law) I am looking for some directions here.
On the one hand, I have a piezoeletric component that needs to be driven by a frequency between 130KHz and 140KHz and I am planning to control this circuit (turn it on/off, change the frequency within this range) using an arduino board. This arduino board will also be connected to other stuff (sensor/actuators).
On the other hand, I have a standalone driving circuit that came with the component (attached here).
Looking at this circuit, I am able to identify the voltage regulator (UA7805) and a few other components that goes along with it: 1x capacitor 330u and 2x 104). I don't fully grasp what goes on when current starts going through this, but I take that it will produce a stable 5V on the other end. So far so good.
(1) The first thing I don't understand is why is there a VCC_5V being regulared but the driving circuit is powered directly by the DC12V instead?
(2) The second thing is that I don't understand how the frequency is generated using the 74132/capacitor/resitors but I will take that as a homework (hints appreciated) and I will read up on it: possibly with more specific questions here later.
(3) The third thing is that I was wondering if there are components/subsets I can trim out of this circuit since I will be using an arduino board to control it. Can an arduino uno board generate these frequencies directly (I am assuming not)? Or do I need a subset of these components (I understand that the 5V will be provided by arduino and I won't need the voltage regulator)?
(4) A final thing is re: power. Since I am planning to use solar power in the future, what is the minimum power I can consume to generate these frequencies?
Any feedback or pointers are well appreciated.
-- yuri