My name is Mike and I'am currently living in the Netherlands. This year I started my first study: electrical engineering
So I went through some things what I could do to help me with my study and came out by the 3x3x3 LED cube.
Now I do understand almost everything and I should order my parts soon. This is my parts list:
-3 2N3904 NPN to use as ground switch (40V/200mA)
-3 22kOhms resistor for the NPN transistors.
-27 green LED's (2.2V/20mA)
-I calculated with this program: http://led.linear1.org/1led.wiz
, that I needed 9*150ohms resistors. Though on the internet
I found that most people uses ~220Ohms resistors. I'm not sure why they do that, so if anyone can tell me I would be thankful
-Perfboard, wires, etc
-Arduino Uno rev1.
Each transistor is connected to 1 of the 3 cathode levels. Then all the 3 transistors are soldered to 1 gnd wire (which then need to plugged in, into a GND port from the arduino).
Each transistor's base is connected to a digital pin from the arduino. When the cube is complete, it does look something like this: http://www.instructables.com/id/LED-Cube-and-Arduino-Lib/step3/Build-the-Circuit/
But I got a couple questions about what I can lit and what I can't:
-How many LED's can I lit up at the same time?
-Is it possible to lit LEDs on two different levels by grounding 2 or 3 levels at the same time and then let a current flow through a column? (So you can get a corner of 3 LEDs lit up the same time, without switching on high frequencies)
-Is it possible to turn on all 9 LEDS at the same time on 1 level?
Thanks in advance for helping a newbie