Alrighty, so I'm an incredible novice for everything electrical and I'm having a hard time finding out what mosfets / transistors / resistors / diodes / whatever else I need and should use for my project.
What I'm doing is building a clock by creating my own 7 segment numbers out of 5050 SMD 12v rgb led strips (common anode). There will be 22 segments in total (7 segments x 3 full numbers + 1 strip for a number one) and each segment has 6 leds for a total maximum power draw of 120mA.
The brains of the operation will be an Arduino Uno (powered by 5v USB from wall). From the Arduino I will have 3 PWM outputs hooked up to an RGB amplifier, which will be powered by a 12v Power Brick. Wires running from the RGB amplifier will run around and ground out the RGB outputs on each LED. I will be using 3 74HC595 Shift Registers to dictate which LEDs should be on or off, but I'm completely lost on what I need to put in between the shift registers, 12v power source, and the LEDs to make it all work.
You really only need 3 TPIC6B595 shift registers.
Each output can sink 15mA from up to a 50V source.
I have this little board with 3 of them and Arduino functionality.
I can send a bootloaded kit for $25, plus $5.25 shipping, and 2.39% paypal fee.
Connect +12V to Vin via barrel jack, Vin on headers goes to + on RGB strips, - on the 8 strips go to the header pins.
Thank you both for the replies! Sorry if it wasn't clear but I have a total of 22 RGB led strips to switch, so correct me if I'm wrong here but I would need a total of 9 TPIC6B595?
So, if I understand correctly what I should do is set up 9 TPIC6B595 (3 for each color) and connect the GND pins to my 12v power sources ground? Then connect the cathode end of the LEDs to a pin on a TPIC6B595. Then, if I set that pin value to high it will block the LED from grounding out, but if it is set to low it will "drain" the LED to ground?
I'm looking at the datasheet for TPIC6B595 (most of the information is over my head), and it appears to have 3 GND connections, do I connect all 3 of these to my 12v source ground? What about the input voltage from my arduino that powers the TPIC6B595, (5v?), where does that get grounded out to? Is it just grounded out to the 12v source? I really don't have much knowledge on electricity but I don't think that will work and I think I need a common ground, right? How exactly would I go about setting up the common ground (assuming the LEDs and arduino are powered from different sources).
I appreciate the offer for the board CrossRoads but I'm doing this mostly as a learning experience and would like to set as much as I can by myself.
