Patent Abstract:
A light dimmer circuit for use with light emitting diodes. Light emitting diodes (LEDs) are connected in parallel with capacitors, which are connected in parallel with LED drivers. The light dimmer circuit is capable of achieving a wide range of power levels to the LEDs.

Full Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present inventive concept relates to a system and method for implementing a light dimmer circuit. 
         [0003]    2. Description of the Related Art 
         [0004]    Light dimmer circuits are known in the art. Lights that use light emitting diodes (LEDs) instead of conventional lights bulbs are sometimes preferred for a number of reasons, for example they may consume less power. Prior art dimmer circuits that are used to power LEDs can subject the LEDs to flicker. 
         [0005]    What is needed is a light dimmer circuit that would reduce flicker and allow the dimmer to dim the LEDs gradually to the full off position. 
       SUMMARY OF THE INVENTION 
       [0006]    It is an aspect of the present general inventive concept to provide an improvement to light dimmer circuits. 
         [0007]    The above aspects can be obtained by an apparatus that includes (a) a dimmer connected to a line voltage; (b) a transformer connected to an output of the dimmer; (c) a first LED driver connected to the transformer, the first LED driver having a first pair of driver terminals; (d) a first capacitor connected in parallel to the first pair of driver terminals; (e) a second LED driver connected to the transformer, the second LED driver having a second pair of driver terminals; (f) a second capacitor connected in parallel to the second pair of driver terminals; (g) a first string of LEDs connected in parallel to the first capacitor; and (h) a second string of LEDs connected in parallel to the second capacitor. 
         [0008]    These together with other aspects and advantages which will be subsequently apparent, reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    Further features and advantages of the present invention, as well as the structure and operation of various embodiments of the present invention, will become apparent and more readily appreciated from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings of which: 
           [0010]      FIG. 1  is a circuit diagram illustrating an exemplary layout of a light dimmer circuit, according to an embodiment; and 
           [0011]      FIG. 2  is a circuit diagram illustrating a second layout of a light dimmer circuit, according to an embodiment. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0012]    Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. 
         [0013]    The general inventive concept relates to a light dimmer circuit that uses one or more capacitors in order to allow for a lower level (even 0%) of power output to LEDs. A standard incandescent light dimmer can be used. 
         [0014]      FIG. 1  is a circuit diagram illustrating an exemplary layout of a light dimmer circuit, according to an embodiment. 
         [0015]    A dimmer  101  is connected to wires which are plugged into a standard 120V AC outlet. The dimmer  101  can a conventional incandescent dimmer, which utilizes a triac, such as Lutron Nova model N600, and outputs to a transformer  100 . The dimmer  101  can be connected to a wall. 
         [0016]    A step down transformer  100  receives the output from the dimmer  101 . The step down transformer can be, for example, a Robertson Transformer model VT536RT180 for 120 VAC line voltage, or a Jard/MARS model 44507, or any other suitable transformer. The transformer can input 120V and lower it to 24V (or other values as well such as 18) which can provide DC voltage at 700 milliamp driving current. 
         [0017]    The step down transformer  100  can be connected to a first LED driver  102  and a second LED driver  104 , connected as shown. The LED drivers can be, for example, a High Perfection Tech p/n CC1512AP-700, or any other suitable LED driver. The first LED driver  102  drives a first pair of driver terminals  105 . The second LED driver  104  drives a second pair of driver terminals  107 . 
         [0018]    The first LED driver  102  is connected to a first capacitor  106  at the first pair of driver terminals  105 , as illustrated. The first capacitor can be, for example, a 6800 uf 25 VDC capacitor (e.g., Nichia p/n UVR1E682MHD), or any other suitable capacitor. A wide range of capacitance values can be used as well and 6800 uf is just one example. The second LED driver  104  is connected to a second capacitor  108  at the second pair of driver terminals  107 , as illustrated. The second capacitor can be, for example, a 6800 uf 25 VDC capacitor (e.g., Nichia p/n UVR1E682MHD), or any other suitable capacitor. A wide range of capacitance values can be used as well and 6800 uf is just one example. While the capacitance of the first capacitor  106  and the second capacitor  108  are equal, they do not necessarily have to be. 
         [0019]    As the dimmer reduces the power output of the transformer  100 , the drivers  102 ,  104  may not react quickly enough which can cause some flicker of the LEDs. Thus, the capacitors  106 ,  108  can maintain the current level while the drivers  102 ,  104  recover. 
         [0020]    Point pairs  112 ,  114 ,  118 ,  124 , can be used with jumpers in order to close the circuit between the respective points or leave it open. A first set of LEDs  110  connected in series and a second set of LEDs  116  connected in series are configured as illustrated. A third set of LEDs  120  connected in series and a fourth set of LEDS  122  connected in series are configured as illustrated. A strand of eight LEDs can use about 15.8 volts, but this can vary according to the LED manufacturer. 
         [0021]    Jumpers can be placed at an of the point pairs. Thus, as one skilled in the art would appreciate, strands of powered LEDs for each driver can comprise either 0 LEDS, 4 LEDs, 8 LEDs, depending on how the jumpers are configured. 
         [0022]    In a further embodiment, instead of using a pair of drivers, a single driver can be used.  FIG. 2  is a circuit diagram illustrating a second layout of a light dimmer circuit, according to an embodiment. 
         [0023]    A dimmer  200  is connected to wires which are plugged into a standard 120V AC outlet. The dimmer  200  can be a conventional incandescent dimmer, which utilizes a triac, such as Lutron Nova model N600, and outputs to a transformer  202 . The dimmer  200  can be connected to a wall. 
         [0024]    The transformer  202  can be a Step-Down Transformer, for example a line to low voltage (e.g., Xicon model 41FJ020). 
         [0025]    The transformer  202  is connected to a LED driver  204 . The LED driver can be, for example, a High Perfection Tech p/n CC1512AP-1000 or equivalent). The LED driver  204  outputs to a pair of driver terminals  205 . 
         [0026]    A capacitor  206  is connected in parallel to the pair of driver terminals  205  and also in series with a connector  208 . The connector  208  can be, for example, a 4 position Molex plug/jack, which is then connected to strands of LEDs. Any number of LEDs (and strands) can be used. The capacitor  206  serves the same purpose as described in  FIG. 1 . The capacitor  206  can be a 6800 uf 25 VDC capacitor (e.g., Nichia p/n UVR1E682MHD or equivalent). Other capacitances can be used as well. 
         [0027]    The many features and advantages of the invention are apparent from the detailed specification and, thus, it is intended by the appended claims to cover all such features and advantages of the invention that fall within the true spirit and scope of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

Technology Classification (CPC): 7