10W-RGB-LED-DRIVER

Version G2

A Constant Current Driver Board for 10W RGB Modules

This circuit board is specifically designed to drive 10W RGB LED modules. It has the ability to drive a 10W RGB LED via a 5v DC PWM signal that will therefore allow dimming of each individual color. As a separate 12V power source is applied to the board, three different connections are made to the board that can control the brightness of each color separately. These connections are typically the 5V DC output pins from a microcontroller.

10W RGB LED

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This board was specifically designed for a commonly found 10W RGB LED. These square form factor LEDs can be found at many online stores, ebay and aliexpress.

Typically characteristics of these LEDs would be:
Color: RGB
DC Forward Voltage (VF): Red 6-8V, Green 9-12V, Blue 9-12V
DC Forward current (IF): 300MA
Output Lumens: Red 120-150LM, Green 200-300LM, Blue 70-100LM
Wave Length : Red 620-625nm , Green 515-520nm, Blue 455-460nm
Beam Angel: 140 degrees
Life span: >50,000 hours

As you can see from the picture to the right, these LEDs are not very large, less than 1" square.
All three colors have a common Anode (+), and separate Cathodes (-) for each color.

Despite their size, do not be fooled into thinking these are like regular indicator LEDs that you see on circuit boards.
These units can generate enough heat to burn themselves out if not attached to a heatsink.

BOM - Bill of Materials

The BOM for this board uses both Surface mount(smd) and through-hole components.
The only mandatory smd part is the constant current driver IC, the PT4115.

The board can use either through-hole or smd inductors. The BOM shows through-hole inductors.

BOM for 12V DC power input:

QTY    Board ID           Description
3      IC1,IC2,IC3        PT4115 by Powtech: 30V, 1.2A Step-down High Brightness LED Driver with 5000:1 Dimming
3      L1,L2,L3           100uH Inductor, 6x8mm, 700ma
3      T1,T2,T3           Transistor  FJN3314R           
3      D1,D2,D3           Diode    1N5819
3      R1,R2,R3           Resistor, 1/4 Watt, 0.33 Ohm
3      R4,R5,R6           Resistor, 1/4 Watt, 4.7K (4K7) Ohm
1      IC4                Voltage Regulator, 5V 78L05
1      C1                 Electrolytic Capacitor 100uF 35v (polarized)
1      C2                 MLCC Ceramic Capacitor .1uF  50v (monolithic)

Assembly

The BOM for this board uses both Surface mount(smd) and through-hole components.
The only mandatory smd part is the constant current driver IC, the PT4115.

The board can use either through-hole or smd inductors. The BOM shows through-hole indu