20W RGB LED Driver Board Assembly (WS2811 version)

BOM

QTY    Part               Description
3      IC1,IC2,IC3        PT4115 constant current buck driver (soldered)
1      IC4                78L05 LDO
1      IC5                WS2811 (soldered)
3      L1,L2,L3           100uH inductor, 6x8mm, 500ma
3      T1,T2,T3           2N3904 transistor           
3      D1,D2,D3           1N5819 diode
3      R1,R2,R3           0.33R  resistor
3      R4,R5,R6           10K resistor
3      R7,R8              33R resistor
1      C1                 47uF/50V capacitor
1      C2                 0.1uF capacitor

Solder resistors

Use as little solder as possible.