I've listed part numbers (current August 2006) which, once you've created an account, you can enter into the 'quick order' form. (please note that the resistors are supplied in packs of 100)
What LEDs to use
Your choice of LED's really depends on what you want to do, how much you want to spend and so on. If you really don't know what you need or where to find suitable LEDs then you might like to try the ones listed below. Although they are rated with a working forward current of 75mA I recommend you stick to around 35mA. If you use these LED's then I'd suggest using the LED current limiting resistors listed.
As an alternative to the 2N7000 MOSFET used for Q1,2,3 & 4 you can substitute a BS170 MOSFET.
If you do this, you must take care to install them correctly. The PCB overlay shows the orientation for a 2N7000. If you use the BS170 you must install them the opposite way round to that shown on the overlay as the Source and Drain connections are reversed.
What PSU to use
The circuit is designed to work with a 12V power supply and this must be a 12 volt regulated DC PSU. The output voltage must be 12 volts under all load conditions; that is whether you have nothing connected to it or several devices attached the output should remain a nominal 12 volts.
The PSU listed below should be adequate for running up to 3 RGB LED Drivers. You should calculate the total current drawn by the LEDs you have used to ensure it is within the rated output of this PSU. A suitable DC power socket to use with it is also listed.
Disclaimer. The part numbers are provided here in good faith but it is up to you to ensure that what you are ordering is both correct and suitable for the intended application.
I am in no way associated with Rapid Electronics. I buy from them myself and have found that they provide reliable and consistently good service and the components are reasonably priced. All the components used in this project are available from other suppliers.