Doing a Country Style track lighting.

Track lighting is another expansion in enriching our homes environment. It gives an extremely lovely lightning effect. One can change its brightening through a control unit in regards to the amount of light is needed. 

They can be introduced in the kitchens and most perfect spot would be the lounge and rooms relying on their shape and the way of the client or occupant. These lights can be set near the windows, flower pots, book retires, and chimneys. 

Track lights don't give brilliant light, yet the general impact is simply enhancing and gives a mood to the room. Specially framed and different shaped lights are accessible for the billiard table, kitchen table and some even molded as country utensils and western legacy ornamental styles. It is most suitable to utilize them where the roof tallness is adequate and the pendant can hand freely. These are found in distinctive shades, for example, nickel, bronze, metal, dark, chestnut, gold, copper, chrome, rust, silver and so on. 

Arrangement should be possible in any structure, as a group forming a triangle, or inline or circle.

These lights must be mounted with the minimum height of 24 to 30 inches over the floor. On the off chance that more than two lights are utilized, customizable bars can be used.

Pure typical country track lights are the, cart wheel, milk jug in copper and brass, spur, lantern, chime, clock and numerous others. Each style likewise speaks to the culture of the district and acts and bringing close the people. They deliver the impact of warmth and convenience which other bright lights and modern lights don't. The costs range from 50 US$ to some even 1000 US$. Organizations into business are additionally offering altered style too. 



Other suitable spots for these lights are on top of the windows, flower pots, fish aquarium, and corners of the dinning room, sitting lounge or family room. You can put them on entryways, stair lobbies where they can be utilized as a part of a solitary line. Lights fit as a fiddle of bell, or cart wheel, or lantern give a delicate look when utilized as a part of the dinning region making the room in all more pleasing and inviting. 

Installation
If you already acquire a ceiling light fixture, track lights are anything but difficult to introduce. Basically remove the old apparatus, screw the track into the roof utilizing toggle botls or other fitting grapples, connect the new track to the electrical box, snap your lights set up and appreciate the enjoyment of moving them around to get the lighting in your room precisely the way you need it!

You can discover boundless approaches to put the track lights in and around your home. The idea is basically to give light and improve style and magnificence of your home with a low power bill. With LED track lighting framework you can make sure of sparing a considerable measure on your energy cost as these don't consume much power.

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Cheapest High power LED driver circuit schematic

There are many other articles on internet with simpler circuits but none of them are cost effective or as cheap as this one.
Using some easy to get cheap components you can make a much better LED driver than you would have thought of.




In market, we can get 1Watt and  3Watt LED easily. And the ratings of those 1Watt LEds are  Forward Voltage 3.2V – 3.6V, Forward Current 300mA and for the 3Watt ones,m the ratings are Forward Voltage: VF3.4V , Forward Current :700mA .

So we consider 3.4volts as optimal voltage, and thus the 1watt LED is giving 3.4×0.3=1.02Watt and for 3watt it is, 2.38Watts.

So here’s the simplest circuit that can be used.

Here, for a fixed reference supply, LM7805 regulator I.C which can deliver upto 1Amps of current, and in our cases the max required current is 700ma or 0.7Amps, so no problem there. And since the resistor “R” will be eating the extra 1.6 volts(5.0-3.4). So what would be the value of R?

For 1 watt model, there’s current of 300mA, so the value of the resistor should be 5.3 Ohms(appx) and wattage should be 0.48. So a 5.6ohms 1/2watt general purpose resistor will do the job perfectly. And similarly, for the 3Watt model, the value of R would be 2.2Ohm 1.25Watt(or 2Watt).

We can feed any voltage greater than 5.5 volts, so we can run this circuit in 6Volts supply or in 12 volts supply.

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Bipolar LED Driver Circuit

A Bi color LED is a special type of LED consists of two diodes connected in inverse direction to each other inside a package. A bi color LED generally consists of three terminals- a common pin and two separate pins. 


 
The common pin can be connected to ground if it is a common anode LED or connected to +5V supply, if it is a common cathode. However there is another type of bi color LED with two terminals. The device functions as per the positive signal given to one of the terminals. For instance for a green and red bi color LED, a positive signal at the green terminal and negative signal at red terminal ensures the green LED to be forward biased and red LED to be reverse biased. This causes the green light to flash. Same is the case for the red LED. However if both the terminals are given negative signals, neither of the diodes would conduct and the device would remain off.  If positive signal is applied to both the terminals, a different color, based on the combination of the LED colors, would flash.

Here, we are designing a simple bi color LED driver circuit using a Microcontroller. The LED used here has a forward voltage drop of 2.2V and hence can be biased using a 5V supply. The control is done by the microcontroller program, based on the inputs given from two push buttons.

Principle Behind Bi-Polar LED Driver Circuit:

The circuit uses a microcontroller to drive the bipolar LED. The input command is given from the three push buttons and based on the inputs; the microcontroller is accordingly programmed to send appropriate signals to the two output pins. These output pins are connected to the terminals of the bi-polar LED.

Bipolar LED Driver Circuit Diagram:

 Bipolar LED Driver Circuit Design:

It is a simple circuit and the design mainly involves designing the interfacing of Microcontroller, designing the oscillator and reset circuits for the microcontroller and selection of the LED resistor.

The microcontroller interfacing is accomplished by connecting two push button switches to port P1 and connecting the two terminals of bi color LED to port P2.

The oscillator design is done by selecting two 10pF ceramic capacitors in order to provide stability. The clock signal is generated using an 11MHz Crystal Oscillator. The reset circuit is designed by selecting an electrolyte capacitor of 10uF and a resistor of 10K to achieve a reset pulse width of 100ms. The voltage drop across the resistor is kept around 1.2V.

The first part of design involves writing the code for the microcontroller. This involves the following steps.

1. Create a new project in the Keil window.
2. Select the target device for the project. Here we select AT89C51 from Atmel.
3. Create a new file such that a blank text field appears.
4. Write the code. The code is written, keeping in mind the following algorithm,
5. Assign a variable to the input and output port.
6. Check if one of the inputs is active low.
7. In case one of the inputs is at logic low, assign a logic high signal to one of the LED terminals.
8. In case none are at logic low, make sure the LED is switched off.
9. Save the code with .c extension.
10. Add the code to the source folder under target folder.
11. Create a Hex file by clicking the ‘Configure Flash Tools’ under ‘Flash’ menu.

The second part involves drawing the circuit on simulation software. Here we use Proteus. The circuit is drawn based on the design method described above.

The third part involves simulating the circuit. This is done by first adding the hex file to the microcontroller and then clicking on the run button.

Working of Bipolar LED Driver Circuit

Once the circuit is switched on, the microcontroller continuously scans the input pins at port P1. Suppose the first button is pressed, the microcontroller receives a low logic signal at the corresponding input pin and accordingly the compiler assigns a high logic signal to pin P0.0 and low logic signal to pin P0.1. This causes the red light of the LED to glow.

Now when the second button is pressed, the compiler will accordingly assign a low logic signal to the pin P0.0 and a high logic signal to pin P0.1. This causes the green light to glow. On pressing the third button, low logic signals will be assigned to both the output pins and the LED will be switched off. In the meanwhile a low logic signal is always given to the common pin.

Bipolar LED Driver Applications:

1. This circuit can be used for indication purposes.
2. This circuit can be used at applications where flashing of light is required, as in beacon flashing.

Limitations of Bipolar LED Driver Circuit:

1. This is a theoretical circuit and may require changes for practical implementations.
2. Most of the bi color LEDs requires higher supply voltage than 5V because of their higher forward voltage rate and this circuit only provides 5V supply voltage to the LED.
3. The LED resistor provides a voltage drop which decreases the biasing voltage of the LED.

  

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