I am a complete amateur when it comes to electronics so forgive me for any misconceptions.
I am trying to design a circuit that will power an RGB LED Strip (here depicted by a single RGB LED), an Arduino Uno (Rev 3), and an HC-06 SPP Bluetooth module.
You probably already guessed that i want to control the color of the LED Strip using the SPP Bluetooth protocol on a smartphone / other SPP capable device. In the picture you can see the circuit i have come up with.
I have a few questions:
- The HC-06 requires 3.3V to work. Is the Arduino Uno supplying 3.3V on the 3V3 rail when the arduino itself is powered off of a 9V Source? I hear the arduino comes equipped with a voltage regulator, so I think the answer is yes.
- Is it a problem that the HC-06 Module running on 3.3V is connected to the shared ground connection of the 9V power source? If i were to use a standalone voltage regulator I would connect it to the GND of output side of the regulator, so just connecting it to a shared ground like this is sounding some alarm bells in my head.
- Is the RGB LED as depicted in this picture common cathode or common anode? In chemistry i learned that Cathodes are positive and Anodes are negative. However, in chemistry we talk about the flow of electrons from negative to positive. In electronics lingo, it flows from positive to negative. Does that mean it is common anode in electronics lingo?