Control the colour of a powerful LED light beam with a remote control, store the colours and recall them at will.
With this thing I can control the colour of a bright light into many different colours using the three fundamentals colours : red green and blue. Adding them toghether with different intensity can yeld very great a range of colours from the visible spectrum.
Specifically my mood lamp can shift colours through 32 intensity values for each RGB colour giving
32*32*32 = 32768 different combinations of hue, intensity and brightness. It can also store 10 different combinations can be turned on or off, all of these through a TV remote control.
The intensity of each red, green and blue component is done via PWM so heat dissipation is kept to a minimum.
The circuit is simple and there are no pushbuttons as control is done entirely through the remote control.
I use this circuit to light a flower vase. The flat case of the box I chose does a good job at balancing the vase.
The pictures provide some ideas.
One day I am possibly buying one of those glass cubes with LASER created 3D shapes inside to go with the lamp. For now glass vases are just fine.
UPDATE : I uploaded V1.1 where at power up the micro outputs the values from memory number 0. Just make sure you store your power up colour in memory number 0 and at power up it will show up. If you'd rather go for lights off, just store all blanks in memory numer 0.
Hey I'm on the best of Instructables book !
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.
Step 1: Description
The LED I chose is a Seoul Semiconductors single chip. It is pretty expensive, but it is powerful giving a very bright light. It provides also an excellent colour blending.
It could be replaced by cheaper and probably equivalent ones; when I designed this, it was the only one suitable I could find.
Due to the LED's high power rating it is absolutely necessary to provide it with a reasonable heat sink like the one you see in the photos; before putting the finished circuit in a case check the LEDs for heat at maximum intensity on all of the three colours. The current limiting resistors I chose match my LED only !
I chose a 10% less than the typical recommended V-I values on the datasheet curves.
Being the circuit in a plastic case it is not safe to pull dissipation any higher while a metallic case with an external dissipation scheme might make safe to pull the LEDs currents a make a more powerful beam.
Different LEDs do have different ratings. Check the datasheets for maximum dissipation and recommendations for your LED.
I purchased my LED online from Distrelec. Farnellinone carries them also.
The drivers are surplus NPN transistors over-dimensioned for the current required. Less powerful TO126 encased NPNs should do fine. As the Transistor are driven with PWM, their dissipation is kept to a minimum so heat sink is not necessary.
The IR receiver is one i savaged from a dead TV toghether with the remote control. The receiver has a metallic screen that should be grounded to 0V. Some newer small-sized ones are from Temic and can be bought from the same sources as above. Practically any receiver works fine, provided that it has 5Volt logic levels (and supply) and has the same (or close) carier frequency as the remote transmitter (typically 38-50kHz). When demolishing a TV or any other remote controlled piece of equipmentm, a good rule is to save both the remote and the receiver. By the way, I love saving transformers, VFD, motors as well, but that's another story.
This lamp uses an european RC5 standard for Philips TV remotes; Any programmable remote control that supports Philips TVs should be fine, I tried one and it works.
Both remote decoding and PWM generating routines should be understandable from the source code I commented.
The circuit must be supplied from a 5 Volt, 1A good source. Initially I used a linear voltage regulator IC on the board into the case, but the heat generated by the regulator was way too much to be easily dissipated from within the box, so I removed it and now I'm using anexternal waal adapter with a regulated 5V 3A output. The LEDs are powered directly from the 5Volt, so any variation would trash your precise calculations for currents to flow through the LEDs, possibly damaging them. So, the better and stable the supply, the better.
The case I chose is a Teko TB9, it looks elegant to me and small transparent objects can be placed on top of the case+LED without the risk of falling.
Step 2: Operation
The remote controls every operation the RGB lamp.
Remote control channel buttons 1, 2 and 3 pull up R, G and B intensity, buttons 4, 5 and 6 pull down the intensity; Channel up and channel down buttons shuffle through the 10 stored values of R G & B intensity.
You can access directly the preset with the 'volume+' button followed by the preset number (0 to 9). You can store your preferred colour pressing 'volume-' followed by the preset number (0 to 9).
The power on/off button does exactly what you might expect : it turns on and off the lamp.
Step 3: Construction
I designed a PCB for the circuit but did not use it. I used perfboard instead.
The pictures should give information enough for anyone willing to replicate exactly what I did. Depending on the height of the box of your choice, the square hole could be not necessary.
Again. keep in mind the heat generated by the LED. Also if you are planning to use this thing to light up a glass object from below, the latter may prevent heat from flowing.
Use a 5Volt regulated wall adapter 1.5A .
During the first uses, monitor the heat generated as it depends a lot from the environment (plastic case, heat insulating stands, objects on the LED).
Never stare at the beam. The light is strong and concentrated.
The microprocessor must be programmed. I used WinPIC. The hardware interface is the one described here.
Attached you can find the schematics, the PCB (check this before, as I never used it !), the source code fully commented and the HEX file to burn directly into the PIC. The software was designed with MPLAB by Microchip.
Hope you enjoy this instructable. If you make your own lamp, please share pictures of your creation and please leave a comment.