Abstract:
An LED device includes a substrate including a first and second light emitting modules, and first and second opposite sides. The first light emitting module includes a first conductive electrode located adjacent to the first side, a second conductive electrode located adjacent to the second side, and a first plurality of light emitting micro diodes electrically connected in the form of a plurality of serially connected bridge rectifiers between the first conductive electrode and the second conductive electrode. The second light emitting module includes a third conductive electrode located adjacent to the first side, a fourth conductive electrode adjacent to the second side, and a second plurality of light emitting micro diodes electrically connected in the form of a plurality of serially connected bridge rectifiers between the third conductive electrode and the fourth conductive electrode. The first, second, third, and fourth conductive electrodes are physically separated from each other.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 61/078,844 filed Jul. 8, 2008, the entirety of which is incorporated by reference herein. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present disclosure relates to alternating current light emitting diodes (AC LED) device, and more particularly, relates to an AC LED device without passive devices. 
     2. Description of the Related Art 
     Light emitting diodes (LED) devices have advantages such as long lifespan and energy efficiency, when compared to other illumination sources. However, conventional LED devices, driven by direct current (DC), require an additional current transducer, to transform alternating current (AC) from an AC power source to direct current. Therefore, a conventional DC device has a larger volume, a higher cost and poorer energy efficiency when compared to a conventional AC LED device. However, conventional LEDs arranged in an AC LED device have poor stability due to variations in driving voltage to the LEDs. For example, if the LEDs of an AC LED device have a small driving voltage, an over-current problem occurs in the circuit while receiving the fixed AC power. Thus, generally, an additional resistor device is coupled to the AC LED device to adjust applied voltage thereto, which increases volume and costs. 
     A novel AC LED device, minimizing driving voltage variations therein and method for fabricating the same are desirable. 
     BRIEF SUMMARY OF INVENTION  
     An LED device comprises: a substrate comprising a first light emitting module, a second light emitting module, a first side, and a second side opposite to the first side; wherein the first light emitting module comprises a first conductive electrode located adjacent to eh first side, a second conductive electrode located adjacent to the second side, and a first plurality of light emitting micro diodes electrically connected in the form of a plurality of serially connected bridge rectifiers between the first conductive electrode and the second conductive electrode; wherein the second light emitting module comprises a third conductive electrode located adjacent to the first side, a fourth conductive electrode adjacent to the second side, and a second plurality of light emitting micro diodes electrically connected in the form of a plurality of serially connected bridge rectifiers between the third conductive electrode and the fourth conductive electrode; and wherein the first, second, third, and fourth conductive electrodes are physically separated from each other for bonding to external bonding structures. 
     A detailed description is given in the following embodiments with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The present disclosure can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein: 
         FIG. 1  shows one exemplary embodiment of an AC LED device of the present disclosure. 
         FIGS. 2   a  to  2   b  show circuitry designs of exemplary embodiments of an AC LED unit chip of the present disclosure. 
         FIGS. 3   a  to  3   c  show circuitry designs of exemplary embodiments of an AC LED unit chip of the present disclosure. 
         FIGS. 4   a  to  4   c  show other exemplary embodiments of an AC LED device of the present disclosure. 
         FIG. 5  shows a circuitry design of one exemplary embodiment of an AC LED unit chip as shown in  FIGS. 4   b  and  4   c.    
         FIG. 6  shows a process chart of fabricating one exemplary embodiment of an AC LED device of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF INVENTION 
     The following description is of a mode of carrying out the present disclosure. This description is made for the purpose of illustrating the general principles of the present disclosure and should not be taken in a limiting sense. The scope of the present disclosure is best determined by reference to the appended claims. Wherever possible, the same reference numbers are used in the drawings and the descriptions to refer the same or like parts. 
     Accordingly, some exemplary embodiments of an alternating current (AC) light emitting diodes (LED) device are provided.  FIG. 1  shows one exemplary embodiment of an AC LED device  500   a  of the present disclosure. As shown in  FIG. 1 , the AC LED device  500   a  comprises a plurality of separated AC LED unit chips  250 , for example, AC LED unit chips  252 ,  254 ,  256  and  258 . In one embodiment, the AC LED unit chips  252 ,  254 ,  256  and  258  may be the same AC LED unit chip. The AC LED unit chip  252  comprises a substrate  200  having two portions  202  and  204 . The portion  202  comprises a first light emitting module  210 , which is composed of a plurality of light emitting micro diodes (not shown), electrically connected between a first conductive electrode  206  and a second conductive electrode  208 . The portion  204  comprises a second light emitting module  216 , which is composed of a plurality of light emitting micro diodes (not shown), electrically connected between a third conductive electrode  212  and a fourth conductive electrode  214 . In one embodiment, the first light emitting module  210  may have the same circuitry as the second light emitting module  216 . A plurality of conductive wires  218   a  to  218   j  are used to electrically connect the separated AC LED unit chips  250 , a node  220  and an alternating current (AC) power supply  222   a  to each other. As shown in  FIG. 1 , two terminals of the conductive wire  218   a  are electrically connected to the first conductive electrode  206  of the AC LED unit chip  252  and the node  220 , respectively. Two terminals of the conductive wire  218   b  are electrically connected to the third conductive electrode  212  of the AC LED unit chip  252  and the node  220 , respectively. Two terminals of the conductive wire  218   c  are electrically connected to the second conductive electrode  208  of the AC LED unit chip  252  and the first conductive electrode  206  of the adjacent AC LED unit chip  254 , respectively. Two terminals of the conductive wire  218   d  are electrically connected to the fourth conductive electrode  214  of the AC LED unit chip  252  and the third conductive electrode  212  of the adjacent AC LED unit chip  254 , respectively. Similarly, the conductive wire  218   e  is respectively and electrically connected to the second conductive electrode  208  of the AC LED unit chip  254  and the first conductive electrode  206  of the adjacent AC LED unit chip  256 . The conductive wire  218   f  is respectively and electrically connected to the fourth conductive electrode  214  of the AC LED unit chip  254  and the third conductive electrode  212  of the adjacent AC LED unit chip  256 . The conductive wire  218   g  is respectively and electrically connected to the second conductive electrode  208  of the AC LED unit chip  256  and the first conductive electrode  206  of the adjacent AC LED unit chip  258 . The conductive wire  218   h  is respectively and electrically connected to the fourth conductive electrode  214  of the AC LED unit chip  256  and the third conductive electrode  212  of the adjacent AC LED unit chip  258 . The conductive wire  218   i  is respectively and electrically connected to the second conductive electrode  208  of the AC LED unit chip  258  and the alternating current (AC) power supply  222   a . The conductive wire  218   j  is respectively and electrically connected to the fourth conductive electrode  214  of the AC LED unit chip  258  and the alternating current (AC) power supply  222   a . Therefore, an LED module chain formed by the first light emitting modules  210  of each of the AC LED unit chips  250  series connected and another LED module chain formed by the second light emitting modules  216  of each of the AC LED unit chips  250 , are, parallel connected between the AC power supply  222   a  and the node  220 , and form the AC LED device  500   a.    
     In one embodiment, the light emitting module of the AC LED unit chip may have various circuitry designs to achieve requirements for adjusting the amount of the light emitting micro diodes that emit light during a positive half cycle of an AC charge, so that they equal to the light emitting micro diodes that emit light during a negative half cycle of an AC charge.  FIGS. 2   a  to  2   b  show circuitry designs of exemplary embodiments of an AC LED unit chip of the present disclosure.  FIG. 2   a  shows a circuitry design of one embodiment of light emitting modules  210  and  216  of an AC LED unit chip  250   a  of the present disclosure. The first light emitting module  210  is electrically connected to the first conductive electrode  206  and the second conductive electrode  208 . The first light emitting module  210  comprises two light emitting units  210   a  and  210   b , parallel connected, wherein the light emitting unit  210   a  is composed of eight light emitting micro diodes  228 , for example, the light emitting micro diodes  228   a  to  228   h , connected in series. As shown in  FIG. 2   a , an anode of the light emitting micro diodes  228   a  is electrically connected to the first conductive electrode  206 , a cathode of the light emitting micro diodes  228   a  is electrically connected to an anode of the adjacent light emitting micro diodes  228   b , a cathode of the light emitting micro diodes  228   b  is electrically connected to an anode of the adjacent light emitting micro diodes  228   c , and so on . . . , and a cathode of the light emitting micro diodes  228   h  is electrically connected to the second conductive electrode  208 . Thus, each light emitting micro diodes  228  of the light emitting unit  210   a  is coupled in a forward conduction direction from the first conductive electrode  206  to the second conductive electrode  208 . Similarly, the light emitting unit  210   b  is composed of eight light emitting micro diodes  228 . Each light emitting micro diodes  228  of the light emitting unit  210   b  is coupled in a forward conduction direction from the second conductive electrode  208  to the first conductive electrode  206 . 
     As shown in  FIG. 2   a , the portion  204  of the AC LED unit chip  250   a  comprises a second light emitting module  216  electrically connected the third conductive electrode  212  and a fourth conductive electrode  214 . The second light emitting module  216  may have the same circuitry design as the light emitting modules  210 . The second light emitting module  216  comprises two light emitting units  216   a  and  216   b , parallel connected, wherein the light emitting unit  216   a  is composed of eight light emitting micro diodes  228  connected in series. Each light emitting micro diodes  228  of the light emitting unit  216   a  is coupled in a forward conduction direction from the fourth conductive electrode  214  to the third conductive electrode  212 . Similar to the light emitting unit  216   a , the light emitting unit  216   b  is composed of eight light emitting micro diodes  228  connected in series. Each light emitting micro diodes  228  of the light emitting unit  216   b  is coupled in a forward conduction direction from the third conductive electrode  212  to the fourth conductive electrode  214 . 
     The described circuitry design of the light emitting module having two light emitting units allows the amount of light emitting micro diodes emitting light during a positive half cycle of an AC charge to equal to that during a negative half cycle of an AC charge. For example, if the AC LED unit chip  250   a  is coupled to an AC power supply, the light emitting module  210  allows the eight light emitting micro diodes of the light emitting unit  210   a  to emit light during a positive half cycle of an AC charge by the AC power supply and allows the eight light emitting micro diodes of the light emitting unit  210   b  to emit light during a negative half cycle of an AC charge by the AC power supply. 
     Generally, a driving voltage of a light emitting micro diode is about 5V. Therefore, a driving voltage of the light emitting modules  210  or  216  composed of eight light emitting micro diodes is about 40V. If the AC LED unit chips of the AC LED device  500   a  as shown the  FIG. 1  are composed of the four AC LED unit chips  250 , a driving voltage of each AC LED unit chips  250  is about 40V, and a peak voltage (Vp) of the AC LED device  500   a  is about 160V. Therefore, the AC power supply  222   a  has a root mean square voltage (Vrms) of about 110V. Thus, a connection type of the AC LED device  500   a  may receive 110 Vrms by an AC power supply, and ten conductive wires are needed. 
     In one embodiment, each light emitting module of each portion of the AC LED unit chip  250   a  may have the same circuitry design and the same amount of light emitting micro diodes. Additionally, each light emitting unit of the same light emitting module may have the same amount of light emitting micro diodes. Alternatively, the amount of light emitting micro diodes of each light emitting unit is according to design, but not limited to the disclosure herein. For example, each light emitting unit of the AC LED unit chip  250   a  may have five to twelve light emitting micro diodes. Therefore, the light emitting module of the AC LED unit chip  250   a  would allow for five to twelve of the light emitting micro diodes to emit light during a positive half cycle of an AC charge, and the same amount for a negative half cycle of an AC charge. A driving voltage of the AC LED unit chip  250   a  is also according to design, but not limited to the disclosure herein. 
     In another embodiment, the amount of light emitting units of each light emitting module of the AC LED unit chip is not limited.  FIG. 2   b  shows a circuitry design of another embodiment of light emitting modules  210  and  216  of an AC LED unit chip  250   b  of the present disclosure. In one embodiment, a driving voltage of the light emitting modules  210  or  216  of the AC LED unit chip  250   b  is about 40V. Alternatively, a driving voltage of the light emitting module of the AC LED unit chip  250   b  is according to design, but not limited to the disclosure herein. The first light emitting module  210  is electrically connected to the first conductive electrode  206  and the second conductive electrode  208 . The first light emitting module  210  comprises eight light emitting units  210   c  to  210   j  series connected. Each light emitting unit, for example, the light emitting unit  210   c , is composed of two light emitting micro diodes  230 , for example, light emitting micro diodes  230   a  and  230   b , parallel connected. The light emitting micro diodes  230   a  of the light emitting unit  210   c  is coupled in a forward conduction direction from the first conductive electrode  206  to the second conductive electrode  208 , but the light emitting micro diodes  230   b  of the light emitting unit  210   c  is coupled in a forward conduction direction from the second conductive electrode  208  to the first conductive electrode  206 . In one embodiment, the eight light emitting units  210   c  to  210   j  may have the same circuitry design. 
     As shown in  FIG. 2   b , the portion  204  of the AC LED unit chip  250   b  comprises a second light emitting module  216  electrically connected to the third conductive electrode  212  and the fourth conductive electrode  214 . The second light emitting module  216  may have the same circuitry design as the light emitting modules  210 . Also, the second light emitting module  216  comprises eight light emitting units  216   c  to  216   j  series connected from the third conductive electrode  212  to the fourth conductive electrode  214 . Each light emitting unit  216  is composed of two light emitting micro diodes  230 , parallel connected. One of the light emitting micro diodes  230  of the light emitting units  216  is coupled in a forward conduction direction from the third conductive electrode  212  to the fourth conductive electrode  214 , but another one of the light emitting micro diodes  230  of the same light emitting units  216  is coupled in a forward conduction direction from the fourth conductive electrode  214  to the third conductive electrode  212 . In this embodiment, each light emitting module of each portion of the AC LED unit chip  250   b  may have the same circuitry design and the same amount of light emitting micro diodes. Each light emitting unit of the same light emitting module may have the same amount of light emitting micro diodes. and the amount of the light emitting units of each portion of the AC LED unit chip  250   b  is according to design, but not limited to the disclosure herein. For example, each light emitting module of the AC LED unit chip  250   b  may have five to twelve light emitting units. In this embodiment, the light emitting module allows the amount of light emitting micro diodes to emit light during a positive half cycle of an AC charge is equal to that during a negative half cycle of an AC charge. For example, the light emitting module would allow five to twelve of the light emitting micro diodes to emit light during a positive half cycle of an AC charge, and the same amount for a negative half cycle of an AC charge. Additionally, the two light emitting micro diodes of one light emitting unit may alternatively emit light during a positive and a negative half cycle of an AC charge. For example, the light emitting micro diodes  230   a  of the light emitting unit  210   c  may emit light if the first conductive electrode  206  receives a positive half cycle of an AC charge, and light emitting micro diodes  230   b  may emit light if the first conductive electrode  206  receives a negative half cycle of an AC charge. 
       FIGS. 3   a  to  3   c  show circuitry designs of exemplary embodiments of an AC LED unit chip of the present disclosure. In embodiments as shown in  FIGS. 3   a  to  3   c , a light emitting module may be composed of one or more bridge light emitting units, wherein a circuit structure of the light emitting micro diodes of each bridge light emitting unit is arranged according to a bridge rectifier. Also, a driving voltage of each light emitting module of each AC LED unit chip as shown in  FIGS. 3   a  to  3   c  is about 40V. Alternatively, a driving voltage of each light emitting module of each AC LED unit chip as shown in  FIGS. 3   a  to  3   c  is according to design, but not limited to the disclosure herein. 
       FIG. 3   a  shows a circuitry design of one embodiment of bridge light emitting units  234   a  and  236   a  of light emitting modules  210  and  216  of an AC LED unit chip  250   c  of the present disclosure. The first light emitting module  210  comprises only one bridge light emitting unit  234   a . The bridge light emitting unit  234   a  has a circuit configuration in a bridge rectifier composed of a first circuit C 1 , a second circuit C 2 , a third circuit C 3 , a fourth circuit C 4  and a fifth circuit C 5 . As shown in  FIG. 3   a , each of the first circuit C 1 , the second circuit C 2 , the fourth circuit C 4  and the fifth circuit C 5  comprises one light emitting micro diode  232 . The third circuit C 3  comprises six light emitting micro diodes  232  series connected. Similarly, the bridge light emitting unit  236   a  of the second light emitting module  216  may have the same circuitry design as the bridge light emitting unit  234   a  of the light emitting modules  210 . The bridge light emitting unit  236   a  has a circuit configuration in a bridge rectifier composed of a first circuit C 1 , a second circuit C 2 , a third circuit C 3 , a fourth circuit C 4  and a fifth circuit C 5 . In the bridge light emitting unit  236   a , each of the first circuit C 1 , the second circuit C 2 , the fourth circuit C 4  and the fifth circuit C 5  comprises one light emitting micro diode  232 , respectively. The third circuit C 3  comprises six light emitting micro diodes  232  series connected. The described circuitry design of the bridge light emitting unit  234   a  or  236   a  allows the amount of light emitting micro diodes emitting light during a positive half cycle of an AC charge to equal to that during a negative half cycle of an AC charge. For example, if the first conductive electrode  206  and the second conductive electrode  208  of the AC LED unit chip  250   c  are coupled to an AC power supply, the light emitting module  210  allows the eight light emitting micro diodes  232 , which comprise one light emitting micro diode  232  of the second circuit C 2 , six light emitting micro diodes  232  of the third circuit C 3  and one light emitting micro diode of the fourth circuit C 4 , to emit light during a positive half cycle of an AC charge by the AC power supply, and the light emitting module  210  allows the eight light emitting micro diodes, which comprise one light emitting micro diode  232  of the fifth circuit C 5 , six light emitting micro diodes  232  of the third circuit C 3  and one light emitting micro diode  232  of the first circuit C 1 , to emit light during a negative half cycle of an AC charge by the AC power supply. If the third conductive electrode  212  and the fourth conductive electrode  214  of the AC LED unit chip  250   c  are coupled to an AC power supply, the light emitting module  216  allows the eight light emitting micro diodes  232 , which comprise one light emitting micro diode  232  of the second circuit C 2 , six light emitting micro diodes  232  of the third circuit C 3  and one light emitting micro diode  232  of the fourth circuit C 4 , to emit light during a positive half cycle of an AC charge by the AC power supply, and the light emitting module  216  allows the eight light emitting micro diodes  232 , which comprise one light emitting micro diode  232  of the fifth circuit C 5 , six light emitting micro diodes  232  of the third circuit C 3  and one light emitting micro diode  232  of the first circuit C 1 , to emit light during a negative half cycle of an AC charge by the AC power supply. Therefore, in the bridge light emitting units  234   a  or  236   a , the light emitting micro diodes  232  of the third circuit C 3  may emit light during a positive or negative half cycle of an AC charge. Additionally, the light emitting micro diodes  232  of the first, second, fourth and fifth circuits C 1 , C 2 , C 4  and C 5  may alternatively emit light during a positive or negative half cycle of an AC charge. 
     Alternatively, the light emitting micro diodes of each circuit of the bridge light emitting unit may have various designs, which would only allow the amount of light emitting micro diodes emitting light during a positive half cycle of an AC charge to equal to that during a negative half cycle of an AC charge.  FIG. 3   b  shows a circuitry design of another embodiment of bridge light emitting units  234   b  and  236   b  of light emitting modules  210  and  216  of an AC LED unit chip  250   d  of the present disclosure. As shown in  FIG. 3   b , a first circuit C 1 , a second circuit C 2 , a fourth circuit C 4  and a fifth circuit C 5  of the bridge light emitting units  234   b  comprise three light emitting micro diodes  232  series connected, respectively. A third circuit C 3  comprises two light emitting micro diodes  232  series connected. Similarly, the bridge light emitting unit  236   b  of the second light emitting module  216  may have the same circuitry design as the bridge light emitting unit  234   b  of the light emitting modules  210 . Therefore, the described circuitry design of the bridge light emitting unit  234   b  of the light emitting module  210  allows the eight light emitting micro diodes  232 , which comprise three light emitting micro diodes  232  of the second circuit C 2 , two light emitting micro diodes  232  of the third circuit C 3  and three light emitting micro diodes  232  of the fourth circuit C 4 , to emit light during a positive half cycle of an AC charge, and the bridge light emitting unit  234   b  allows the eight light emitting micro diodes  232 , which comprise three light emitting micro diodes  232  of the fifth circuit C 5 , two light emitting micro diodes  232  of the third circuit C 3  and three light emitting micro diodes  232  of the first circuit C 1 , to emit light during a negative half cycle of an AC charge. 
     Also, the described circuitry design of the bridge light emitting unit  236   b  of the light emitting module  216  allows the eight light emitting micro diodes  232 , which comprise three light emitting micro diodes  232  of the second circuit C 2 , two light emitting micro diodes  232  of the third circuit C 3  and three light emitting micro diodes  232  of the fourth circuit C 4 , to emit light during a positive half cycle of an AC charge, and the bridge light emitting unit  236   b  of the light emitting module  216  allows the eight light emitting micro diodes  232 , which comprise three light emitting micro diodes  232  of the fifth circuit C 5 , two light emitting micro diodes  232  of the third circuit C 3  and three light emitting micro diodes  232  of the first circuit C 1 , to emit light during a negative half cycle of an AC charge. 
     Also, in the bridge light emitting units  234   b  or  236   b , the light emitting micro diodes  232  of the third circuit C 3  may emit light during a positive or negative half cycle of an AC charge. Additionally, the light emitting micro diodes  232  of the first, second, fourth and fifth circuits C 1 , C 2 , C 4  and C 5  may alternatively emit light during a positive or negative half cycle of an AC charge. 
     In other embodiments, the light emitting module may be composed of a plurality of the bridge light emitting units.  FIG. 3   c  shows a circuitry design of another embodiment of bridge light emitting units  234   c ,  234   d ,  236   c  and  236   d  of light emitting modules  210  and  216  of an AC LED unit chip  250   e  of the present disclosure. The first light emitting module  210  comprises two bridge light emitting units  234   c  and  234   d  series connected from the first conductive electrode  206  to the second conductive electrode  208 . Each of the bridge light emitting units  234   c  and  234   d  has a circuit configuration in a bridge rectifier composed of a first circuit C 1 , a second circuit C 2 , a third circuit C 3 , a fourth circuit C 4  and a fifth circuit C 5 . As shown in  FIG. 3   c , each of the first circuit C 1 , the second circuit C 2 , the fourth circuit C 4  and the fifth circuit C 5  comprises one light emitting micro diode  232 . The third circuit C 3  comprises two light emitting micro diodes  232  series connected. Similarly, the bridge light emitting units  236   c  and  236   d  of the second light emitting module  216  may have the same circuitry design as the bridge light emitting units  234   c  and  234   d  of the light emitting modules  210 . Therefore, the described circuitry design of the light emitting module  210  comprising the bridge light emitting units  234   c  and  234   d  allows the eight light emitting micro diodes  232 , which comprise one light emitting micro diode  232  of the second circuit C 2  of the bridge light emitting units  234   c  and  234   d , two light emitting micro diodes  232  in the third circuit C 3  of the bridge light emitting units  234   c  and  234   d  and one light emitting micro diode  232  in the fourth circuit C 4  of the bridge light emitting units  234   c  and  234   d , to emit light during a positive half cycle of an AC charge, and the bridge light emitting units  234   c  and  234   d  allow the eight light emitting micro diodes  232 , which comprise one light emitting micro diode  232  of the fifth circuit C 5  of the bridge light emitting units  234   c  and  234   d , two light emitting micro diodes  232  of the third circuit C 3  of the bridge light emitting units  234   c  and  234   d  and one light emitting micro diode  232  of the first circuit C 1  of the bridge light emitting units  234   c  and  234   d , to emit light during a negative half cycle of an AC charge. 
     Also, the described circuitry design of the light emitting module  216  comprising the bridge light emitting units  236   c  and  236   d  allows the eight light emitting micro diodes  232 , which comprise one light emitting micro diodes  232  of the second circuit C 2  of the bridge light emitting units  236   c  and  236   d , two light emitting micro diodes  232  in the third circuit C 3  of the bridge light emitting units  236   c  and  236   d  and one light emitting micro diodes  232  in the fourth circuit C 4  of the bridge light emitting units  236   c  and  236   d , to emit light during a positive half cycle of an AC charge, and the bridge light emitting units  236   c  and  236   d  allows the eight light emitting micro diodes  232 , which comprise one light emitting micro diodes  232  in the fifth circuit C 5  of the bridge light emitting units  236   c  and  236   d , two light emitting micro diodes  232  in the third circuit C 3  of the bridge light emitting units  236   c  and  236   d  and one light emitting micro diodes  232  in the first circuit C 1  of the bridge light emitting units  236   c  and  236   d , to emit light during a negative half cycle of an AC charge. 
     Also, in the bridge light emitting units  234   c ,  234   d ,  236   c  or  236   d , the light emitting micro diodes  232  of the third circuit C 3  may emit light during a positive or negative half cycle of an AC charge. Additionally, the light emitting micro diodes  232  of the first, second, fourth and fifth circuits C 1 , C 2 , C 4  and C 5  may alternatively emit light during a positive or negative half cycle of an AC charge. 
     The described circuitry design of the light emitting module composed of one or more bridge light emitting units allows the amount of light emitting micro diodes emitting light during a positive half cycle of an AC charge to equal to that during a negative half cycle of an AC charge. The amount of the bridge light emitting units of each light emitting module is according to design, but not limited to the disclosure herein. Also, the amount of the light emitting micro diodes of each circuit of each bridge light emitting unit is according to design, but not limited to the disclosure herein. For example, each bridge light emitting unit of the AC LED unit chip may allow five to twelve light emitting micro diodes to emit light during a positive half cycle and a negative half cycle of an AC charge, and all the light emitting micro diodes in the third C 3  of the bridge light emitting unit may emit light during a positive and negative half cycles of an AC charge. 
     The described AC LED unit chips may have various connection types to form an AC LED device, receiving different applied voltages by an AC power supply. FIGS.  4   a  to  4   c  show other exemplary embodiments of an AC LED device of the present disclosure. In one embodiment, a driving voltage of each light emitting module of each AC LED unit chip as shown in  FIGS. 4   a  to  4   c  is about 40V. Alternatively, a driving voltage of each light emitting module of each AC LED unit chip as shown in  FIGS. 4   a  to  4   c  is according to design, but not limited to the disclosure herein. As shown in  FIG. 4   a , the AC LED device  500   b  comprises a plurality of separated AC LED unit chips  250 , for example, AC LED unit chips  252 ,  254 ,  256  and  258 . In one embodiment, the AC LED unit chips  252 ,  254 ,  256  and  258  may be the same AC LED unit chip. The light emitting modules  210  and  216  of the light emitting unit chips  252 ,  254 ,  256  or  258  may have the same circuitry designs, which are shown in  FIGS. 2   a  to  2   b  and  3   a  to  3   c . A plurality of conductive wires are used to electrically connect the light emitting unit chips  252 ,  254 ,  256  or  258 , the node  220  and an AC power supply  222   b  to each other to form the AC LED device  500   b . As shown in  FIG. 4   a , a conductive wire  224   a  is electrically connected to the node  220  and the first conductive electrode  206  of the AC LED unit chip  252 . Conductive wires  224   b ,  224   d ,  224   f  and  224   h  are respectively and electrically connected to the second conductive electrodes  208  of the AC LED unit chips  252 ,  254 ,  256  and  258  and the fourth conductive electrodes  214  of the same AC LED unit chips  252 ,  254 ,  256  and  258 . Conductive wires  224   c ,  224   e  and  224   g  are respectively and electrically connected to the third conductive electrodes  212  of the AC LED unit chips  252 ,  254  and  256  and the first conductive electrodes  206  of the adjacent AC LED unit chips  254 ,  256  and  258 . A conductive wire  224   i  is electrically connected to the third conductive electrodes  212  of the AC LED unit chip  258  and the AC power supply  222   b . As shown in  FIG. 4   a , the AC LED unit chips  252 ,  254 ,  256  and  258  are series connected from the AC power supply  222   b  to the node  220  with the light emitting modules  210  and  216  of each AC LED unit chips  252 ,  254 ,  256  and  258  series connected. Therefore, the AC LED device  500   b  is formed. As mentioned before, driving voltages of the light emitting modules  210  and  216  of each AC LED unit chips  252 ,  254 ,  256  and  258  are about 40V, and a peak voltage (Vp) of the AC LED device  500   b  is about 320V. Therefore, the AC power supply  222   b  may have a root mean square voltage (Vrms) of about 220V. That is to say, a connection type of the AC LED device  500   b  may receive 220Vrms of applied voltage by an AC power supply, and nine conductive wires are needed. 
       FIG. 4   b  show a connection type of another exemplary embodiment of an AC LED device  500   c  of the present disclosure. As shown in  FIG. 4   b , the AC LED device  500   c  comprises a plurality of separated AC LED unit chips  260 , for example, AC LED unit chips  262 ,  264 ,  266  and  268 . In one embodiment, the AC LED unit chips  262 ,  264 ,  266  and  268  may be the same AC LED unit chip.  FIG. 5  shows a circuitry design of one exemplary embodiment of an AC LED unit chip  262  as shown in  FIGS. 4   b  and  4   c . The light emitting modules  310  and  316  of the light emitting unit chips  262  may have the same circuitry designs as the light emitting modules  210  and  216  as shown in  FIG. 3   c . Alternatively, the light emitting modules  310  and  316  of the light emitting unit chips  262  may have the same circuitry designs as the light emitting modules  210  and  216  as shown in  FIGS. 2   a  to  2   b ,  3   a  and  3   b , but not limited to the disclosure herein. As shown in  FIG. 5 , it is noted that the light emitting modules  310  and  316  of the same light emitting unit chip  262  share the same conductive electrode  306 . As shown in  FIG. 4   b , the light emitting modules  310  and  316  of the same light emitting unit chip, for example, the light emitting unit chip  262 , share the same conductive electrode, for example, the first conductive electrode  306 . Therefore, the node  220  is electrically connected to the light emitting modules  310  and  316  by only one conductive wire through the first conductive electrode  306  shared by the light emitting modules  310  and  316 . Thus, because the amount of conductive wires is reduced, so may costs. Additionally, the light emitting modules  310  and  316  of the light emitting unit chips  262 ,  264 ,  266  or  268  may have the same circuitry designs. A plurality of conductive wires are used to electrically connect the light emitting unit chips  262 ,  264 ,  266  or  268 , the node  220  and an AC power supply  222   c  to each other to form the AC LED device  500   b . A conductive wire  226   a  is respectively and electrically connected to the node  220  and the first conductive electrode  306  of the AC LED unit chip  262 . Conductive wires  226   b  and  226   e  are respectively and electrically connected to the second conductive electrodes  308  of the AC LED unit chips  262  and  266  and third conductive electrodes  314  of the adjacent AC LED unit chips  264  and  268 . Conductive wires  226   c  and  226   f  are respectively and electrically connected to third conductive electrodes  314  of the AC LED unit chips  262  and  266  and second conductive electrodes  308  of the adjacent AC LED unit chips  264  and  268 . A conductive wire  226   d  is electrically connected to the first conductive electrodes  306  of the AC LED unit chip  264  and the adjacent AC LED unit chip  266 . A conductive wire  226   g  is electrically connected to the first conductive electrodes  306  of the AC LED unit chip  268  and the AC power supply  222   c . As shown in  FIG. 4   b , an LED module chain is formed by connecting the light emitting module  316  of the AC LED unit chip  262 , the light emitting module  310  of the AC LED unit chip  264 , the light emitting module  316  of the AC LED unit chip  266  and the light emitting module  310  of the AC LED unit chip  268  in series. Another LED module chain is formed by connecting the light emitting module  310  of the AC LED unit chip  262 , the light emitting module  316  of the AC LED unit chip  264 , the light emitting module  310  of the AC LED unit chip  266  and the light emitting module  316  of the AC LED unit chip  268  in series. The described two LED module chains are, parallel connected between the node  220  and the AC power supply  222   b . Therefore, the AC LED device  500   c  is formed. As mentioned before, driving voltages of the light emitting modules  310  and  316  of each AC LED unit chips  262 ,  264 ,  266  and  268  are about 40V, and a peak voltage (Vp) of the AC LED device  500   c  is about 160V. Therefore, the AC power supply  222   c  may have a root mean square voltage (Vrms) of about 110V. That is to say, a connection type of the AC LED device  500   c  may receive 110Vrms applied voltage by an AC power supply, and seven conductive wires are needed. When compared with the connection type of the AC LED device  500   a  as shown in  FIG. 1 , the AC LED device  500   c  has less conductive wires. Therefore, the AC LED device  500   c  may have a lower fabricating cost than the AC LED device  500   a.    
       FIG. 4   c  show a connection type of another exemplary embodiment of an AC LED device  500   d  of the present disclosure. Also,  FIG. 5  shows a circuitry design of one exemplary embodiment of an AC LED unit chip  262  as shown in  FIGS. 4   b  and  4   c . The light emitting modules  310  and  316  of the light emitting unit chips  262  may have the same circuitry designs as the light emitting modules  210  and  216  as shown in  FIG. 3   c . Alternatively, the light emitting modules  310  and  316  of the light emitting unit chips  262  may have the same circuitry designs as the light emitting modules  210  and  216  as shown in  FIGS. 2   a  to  2   b ,  3   a  and  3   b , but not limited to the disclosure herein. Similar to the AC LED device  500   c , the light emitting modules  310  and  316  of the same light emitting unit chips  262 ,  264 ,  266  or  268  share the same conductive electrode  306 . Therefore, the light emitting modules  310  and  316  of the same light emitting unit chip, for example, the light emitting unit chip  262 , may be series connected without conductive wires. The cost of the conductive wires may be reduced. A plurality of conductive wires are used to electrically connect the light emitting unit chips  262 ,  264 ,  266  or  268 , the node  220  and an AC power supply  222   d  to each other to form the AC LED device  500   d . As shown in  FIG. 4   c , a conductive wire  228   a  is electrically connected to the node  220  and the third conductive electrode  314  of the AC LED unit chip  262 . Conductive wires  228   b ,  228   c  and  228   d  are respectively and electrically connected to the second conductive electrodes  308  of the AC LED unit chips  262 ,  264  and  266  and the third conductive electrodes  314  of the adjacent AC LED unit chips  264 ,  266  and  268 . A conductive wire  228   e  is electrically connected to the second conductive electrodes  308  of the AC LED unit chip  268  and an AC power supply  222   d . Similar to the AC LED device  500   b , the AC LED unit chips  262 ,  264 ,  266  and  268  are series connected from the AC power supply  222   d  to the node  220  with the light emitting modules  310  and  316  of each AC LED unit chips  262 ,  264 ,  266  and  268  series connected. Therefore, the AC LED device  500   d  is formed. As mentioned before, driving voltages of the light emitting modules  210  and  216  of each AC LED unit chips  252 ,  254 ,  256  and  258  are about 40V, and a peak voltage (Vp) of the AC LED device  500   d  is about 320V. Therefore, the AC power supply  222   b  may have a root mean square voltage (Vrms) of about 220V. That is to say, a connection type of the AC LED device  500   d  may receive 220Vrms applied voltage by an AC power supply, and five conductive wires are needed. When compared with the connection type of the AC LED device  500   b  as shown in  FIG. 4   a , the AC LED device  500   d  has less conductive wires. Therefore, the AC LED device  500   d  may have a lower fabricating cost than the AC LED device  500   b.    
     The described AC LED device connection types, as shown in  FIGS. 1 ,  4   a  to  4   c , are formed by connecting each light emitting module of each AC LED unit chips in a series or a parallel connection. Alternatively, the amount of AC LED unit chips is according to design to receive different root mean square applied voltages, for example, 90Vrms, 100Vrms, 110Vrms, 132Vrms, 150Vrms, 162Vrms, 240Vrms or 264Vrms. Additionally, each light emitting module of each AC LED unit chip may have various designs to have different driving voltages. Therefore, the AC LED unit chip composed of the light emitting modules may receive different applied voltages. 
       FIG. 6  shows a process chart of fabricating one exemplary embodiment of an AC LED device of the present disclosure. As shown in step  1610 , the step of fabricating the AC LED device comprises fabricating the light emitting unit chips. As shown in step  1620 , the light emitting unit chips are sorted by measuring their driving voltages. As shown in step  1630 , the sorted light emitting unit chips are selected to compose an AC LED device that receives a predetermined voltage. As shown in step  1640 , the selected and sorted light emitting unit chips are connected to each other by bonding conductive wires to form an AC LED device that receives a predetermined voltage. For example, if the driving voltage levels of the sorted light emitting unit chips comprise 36Vrms, 40Vrms and 44Vrms. an AC LED unit chip receiving 160Vrms driving voltage may be composed by connecting two light emitting unit chips of 36Vrms driving voltage and two light emitting unit chips of 44Vrms driving voltage. In another embodiment, the AC LED unit chip receiving 160Vrms driving voltage may be composed by connecting one light emitting unit chip of 36Vrms driving voltage, one light emitting unit chip of 44Vrms driving voltage and two light emitting unit chips of 40Vrms driving voltage. Alternatively, the AC LED unit chip receiving 160Vrms driving voltage may be composed by connecting four light emitting unit chips of 40Vrms driving voltage, but not limited to the disclosure herein. When compared with the conventional AC LED device, whereby all LEDs are arranged in one chip to receive a specific voltage, one exemplary embodiment of an AC LED device composed of one or more AC LED unit chips may receive different applied voltages without requirement to change circuitry designs. Additionally, exemplary embodiments of the AC LED unit chips have smaller driving voltage variations. The AC LED unit chips may be selected and sorted to compose an AC LED device, whereby a predetermined voltage receives and no passive device to adjust applied voltages is required. 
     While the present disclosure has been described by way of example and in terms of the preferred embodiments, it is to be understood that the present disclosure is not limited to the disclosed embodiments. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.