In order to get a feel for current “exotic” lighting solutions I decided to place an order for one of these kit’s on ebay:
“5M 500cm SMD 5050 RGB 150 LED Strip + IR Remote” The name gives no suggestion as to what it was primarily designed for.
I purchased a 5M kit as I thought the RGB LED strip was something I would use in my system. The Advert stated the following
- Superbright 5050 SMD top LED, high intensity and reliability.
- Continuous length, packed with 5 meter.
- Cuttable every 3 LEDs along the cutting marks, according to pratical requirement.
- Long life span 50,000+ hours
- Flexible ribbon for curving around bends
- Completely smooth and even light spread, solving the uneven luminous problem
- Ultra-bright but running at low temperature
- Self-adhesive back with 3M double side adhesive tape
- Certification: CE & RoHS
- Low power consumption
The stated specifications of the kit were as follows:
- LED Type: 5050 PLCC-6 SMT SMD LED (Non-Waterproof)
- Color: 16 solid colors options
- Different lights changing modes: Flash, Strobe, Fade, and Smooth
- LED Quantity: 150 leds/5 Meter or 30 leds/Meter
- Size: L500cm (5M) x W1.40cm x T0.40cm
- Package: 5 Meters / Reel
- View angle:120°
- Working Input Voltage: 12VDC
- Working Current/meter: 0.6A
- Output power: 36W /5 Meter
- Working Tempreture:-20° to 50°
- PCB Background: Brown
- Water Proof: IP 0
- Drive Mode:Contant Voltage
In the box
The package came with 3 items:
- 5m rgb led Strip (150 LEDs)
- LED Controller / Driver
- IR Remote Control
The LED Controller / Driver
The LED Controller driver specs were printed on the top. It can drive an impressive 6 Amps.
Its a fairly simple unit from the outside. It has a DC input jack and a cable with a connector on the end for the output to the LED strip. Also on the end of a short cable is an IR receiver. There is no switches or controls of any kind on the unit. It was also noted that for a unit which can handle 6A it has no clear holes for heat exchange.
On the output connector there is an arrow to denote the 12V positive line.
IR Remote Control
Slightly smaller in every dimension bar thickness than my campus card. The Control offers mode selection between 4 modes, although on my unit these seemed to be named incorrectly! The offerings are Flash, Strobe, Fade and Smooth. There are two buttons dedicated to dimming control. When they are pushed the lights dim in visible jumps. You also cannot hold either dim button to continue to minimum or maximum, you must repeatedly push the buttons.
Close up the controller worked very well but walk across the room and you had to point pretty accurately to get any response.
The vast majority of the controllers 24 buttons are colour selection pre-sets. The top line of colours gives options for pure red, green and blue as well as white which turns on all colours. The other buttons are pre-set colour mixes.
There is also buttons for power control.
The LED Strip
The LED strip supplied had 30 RGB LED’s per meter. To quote the specifications, each meter at full power is to draw 600ma. They are cables with a common positive rail of 12v. Each set of 3 LED’s has 3 resistors. It seems one for each channel, red, green and blue.
The strip can be cut on the marking (Below) which appears either side of groups of 3 LED’s (Above).
The LED’s mounted on the strip are called “SMD 5050 RGB” units. They have 6 pins and give you access to both anode and cathode of each of the RGB LED’s within.
The first thing to note is the lack of power supply in the kit. To power the system up I had to use my bench supply.
The specs above say that current consumption is 0.6A per meter. At 5 meters we should expect to consume a maximum of 3A. 3A 12V power supplies are not most commonly available.
No visible flickering is seen when fully dimmed which suggests PWM frequency is high.
Some Photos showing colours:
Inside the eBay purchased LED strip controller
This page mainly consists of annotated pictures. Annotations highlight useful design features and components.
- Thick PCB tracks. Power is separated from more precision electronics below
- 3 Power MOSFETs
- 15N03H – N-Channel Enhancement Mode Power Mosfet
- Absolute Max Rating of 15A @ 10V
- RDS when ON is 80 mOhms
- More delicate electronics on the back
- MOSFETs gates connected through resistors to MCU
- Larger IC seems to be MCU but is unbranded
- Smaller IC has no English data sheet available
- Reverse polarity protection diode.
- Voltage Regulator for MCU and other components
- Closer shot of IC with no English data sheet.