High-Power RGB LED Driver
Features and Benefits
e
gunten
on
v
ngineerin
Single Input Voltage
Constant-Current Control
Efficient Buck Regulator
PWM Dimmable in 255 steps
DMX / RS485 / RF-ISM option
PR
Configurable via Hard- and Software
True average output current control
Undervoltage lockout
Thermal shutdown protection
Protection against open/short faults
In System Programmable Atmel AVR Micro Controller
Description
EL
Three individual switching regulators for each color provide constant-current output to drive high-power
RGB LEDs. These integrate a high-side N-channel DMOS switch for DC-to-DC step-down (buck)
conversion. A true average current IAVG is output using a cycle-by-cycle, controlled on-time method.
Output current for each color is user-selectable by a current sense resistor: Rs = 0.2V / IAVG.
Output voltage is automatically adjusted to drive various numbers of LEDs in a single string.
This ensures the optimal system flexibility and efficiency.
IM
Various communication protocols are implemented with the Atmel AVR onboard Micro Controller.
This allows wired LED control using the DMX standard or any other RS-485 / RS-232 based
communication.
RY
A
IN
Connecting a RF-ISM module allows wireless LED control. XBee adaptors (like https://learn.adafruit.
com/xbee-radios) or IQRF transceiver modules (e.g. the TR-52D series from http://www.iqrf.org/) can
be directly connected to the driver board.
LED dimming is accomplished by a pulse width modulation signal allowing 255 steps of brightness for
each color - thus a theoretical range of 16 million colors.
Thermal protection is achieved supporting two LM60 temperature sensors, one onboard and one on
the LED heat sink. Active cooling of the board might be required when output power exceeds 100 Watt.
All electrical board connections are done through standard board-to-wire connectors.
Seven 2.2mm diameter holes (all tinned to GND) allow mechanical fixture and may increase thermal
dissipation.
Electrical Characteristics
VIN
IAVG of single LED
LED ripple current
LED forward voltage
8 V ... 48 V
0.2 A ... 2.0 A
20 ... 40 % of IAVG
10 V ... 36 V (auto adj.)
Mechanical Characteristics
http://www.EngVG.ch
info@EngVG.ch
+41 31 511 9649
Switching frequency
Efficiency
PWM duty cycle (fPWM)
LED Power
1 MHz
>90 %
255*30µs (131 Hz)
10 W ... 200 W
Board dimensions
Board weight
110x34x15 mm
30 g
© Engineering von Gunten / March 2015
Page 1/2
e
High-Power RGB LED Driver
Application Examples
gunten
on
v
ngineerin
10 Watt RGB Power LED
VIN
IAVG of red LED
IAVG of green LED
IAVG of blue LED
LED forward voltage
12 V ... 15 V
0.29 A
Rs=680mΩ
0.29 A
Rs=680mΩ
0.29 A
Rs=680mΩ
8 V ...11 V (auto adjusted)
PR
100 Watt RGB High Power LED
40 V ... 48 V
1.11 A
Rs=180mΩ
1.00 A
Rs=200mΩ
1.33 A
Rs=150mΩ
20 V ... 36 V (auto adjusted)
EL
VIN
IAVG of red LED
IAVG of green LED
IAVG of blue LED
LED forward voltage
... other configurations supported by changing few board components... please ask us!
Phoenix Contact 1840366
Phoenix Contact 1840405
TE Connectivity 215297-4
JST ZHR-3
RD
http://www.EngVG.ch
info@EngVG.ch
+41 31 511 9649
GN
Digi-Key 277-2417-ND
Digi-Key 277-2414-ND
Digi-Key A106651-ND
Digi-Key 455-1160-ND
Farnell 5088951
Farnell 5088999
Farnell 3419060
Farnell 3357557
Ext. Temp.
VIN
Maximum Input
Voltage < 50 V
BL
© Engineering von Gunten / March 2015
A / DMX+
NC
B / DMXGND
LM60
+
cathode anode +
cathode anode +
Common Anode or
Common Cathode
on RGB LED
MUST be avoided!
cathode anode +
GND
Vout
+Vs
VIN
RGB LEDs
RS-485 / DMX
External LM60
RY
A
IN
X1
X2
X3
X6
IM
Cable Connectors
RS-485 / DMX
Page 2/2