Component List

If you're in the UK you can buy all the components you need to build the Serial Controlled or Stand Alone RGB LED Driver from Rapid Electronics *

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)

R1 PK 100 100K 0.125W CF RESISTOR (RC) 64-0124
R2 PK 100 4K7 0.125W CF RESISTOR (RC) 64-0092
C1 100N 2.5MM X7R DIELEC.CERAMIC (RC) 08-1015  
C3 220N 5MM Y5V DIELECT.CERAMIC (RC) 08-0280
D1 1N4148 200mA 100V SILICON RECTIFIER DIODE RC 47-3308  
Q1,2,3,4 2N7000 N CHANNEL MOSFET (RC) 47-0180  
alternative BS170 N CHANNEL MOSFET (RC) (see below) 47-0142  
VR1 DA78L05 V REG +5V 1A TO-92 (RC) 47-3612
U1 PIC12F629-I/P (RC)  (You can also use a PIC12F675 or 683 but the 629 is generally cheaper) 73-3262
Socket for U1 8 PIN 0.3IN DIL SOCKET 22-0150  
  • If you build the serial controlled version you can omit SW1
  • If you build the standalone version you can omit Q4, R1 and R2.
  • You may want to check out the Rapid Electronics website for other parts you may need such as connecting wire, PCB mounting pillars, connectors, PSUs etc.

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.

Red LED x 4 LED 5MM RED 70000MCD (RC)    55-1824  
Green LED x 3 LED 5MM GREEN 70000MCD (RC) 55-1828  
Blue LED x3 LED 5MM BLUE 15000MCD (RC) 55-1830  
Rled, Gled   & Bled resistors PACK 100 39R 0.25W CF RESISTOR (RC) 62-0336  

Alternative MOSFET

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.

BS170 pinout


2N7000 pinout

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.

Connector 2.1MM SINGLE HOLE CHASSIS SKT (RC) 20-0980  


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.