Patent Publication Number: US-11378237-B2

Title: Illuminated Christmas tree decorative light control circuit

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates to the technical field of a control circuit, and in particular, to an illuminated Christmas tree decorative light control circuit. 
     2. Description of Related Art 
     Pine or evergreen trees are often brought home to be used as part of the Christmas celebration, and it is a tradition to use ornaments, decorative lights, flower rings and ribbons etc. for the decoration of Christmas trees. In addition, to satisfy the environmental protection and energy saving demands of the modern society, decorative lights using LEDs as the light source are becoming more popular and are widely used for the decoration of Christmas trees. 
     Common LED decorative lights mostly combine a plurality of LED illuminating elements onto an elongated circuit in order to form a light string (light strip) having a fixed length specification (3M, 4M, 7M). In addition, to allow the light string (light strip) to have different lighting modes, typically, it is necessary to use a controller with built-in control program to control the light string (light strip), thereby allowing it to form a light strip module having various illumination changing effects (such as: flash frequency, alternating or illumination in turns etc.). 
     However, since most Christmas trees typically have a lot of main branches on the trunk, and each main branch can also have further termination branches extended therefrom. If one single light strip module is used to decorate a Christmas tree, since it is necessary to wrap the light strip module between the trunk and the main branches repetitively, the termination branches often cannot be decorated completely due to insufficient length of the light strip module. A feasible solution is to connect the rear end of the original light strip module to another light string (light strip) in order to extend the overall length of the light strip module to a sufficient length. Nonetheless, the length of the light strip module becomes extremely long, causing the construction work to be difficult and the overall circuit becomes messy, and the repair work during malfunction also becomes difficult. 
     Furthermore, if a plurality of light strip modules are jointly decorated onto one single Christmas tree, then despite that a light strip module can be installed on each relatively large main branch and the aforementioned drawback can be improved, the wiring distribution of the overall decorative light becomes relatively simple and standard. However, in terms of the actual use, since each light strip module has an independent controller, the situation where the lighting mode of each light strip module may not be controlled uniformly may occur. Moreover, the plurality of light strip modules installed can also cause the overall construction cost to increase, such that it is not economically cost effective. 
     BRIEF SUMMARY OF THE INVENTION 
     A primary objective of the present invention is to provide an illuminated Christmas tree decorative light control circuit, which utilizes a single main controller installed at the bottom portion of the tree trunk for connecting to and controlling a plurality of branch controllers installed on each main tree branch; in addition, each branch controller is further connected to and controlling the decorative light modules (light string/light strip equipped with a plurality of LED arranged linearly) on each tree branch, such that it is optimal and suitable to the decorative light control of a Christmas tree having complicated tree branches. During the construction, each decorative light module can be installed on each tree branch independently first, followed by connecting the plurality of decorative light modules to the corresponding branch controllers respectively. Next, all of the branch controllers are connected to the main controller in order to allow the main controller to uniformly control each decorative light module via each branch controller, thereby achieving the objectives of simplified construction procedure and neatly arranged circuits. 
     To achieve the aforementioned objectives and technical effects, the control circuit of the present invention comprises a main controller  1  and at least one branch controller  2  electrically connected to the main controller  1 . The main technical features adopted rely in: the main controller  1  comprising a main control circuit  11  and a control output circuit  16 , the main control circuit  11  having a main control chip U 1  arranged therein, the main control chip U 1  configured to generate and output a control signal for a plurality of lighting modes via a built-in dimming control program, the control output circuit  16  configured to receive the control signal outputted by the main control circuit  11  and convert it to output a main control signal; each one of the branch controllers  2  comprising a signal transmission circuit  21 , a driving circuit  22  and a connecting terminal PIN, the signal transmission circuit  21  configured to receive the main control signal outputted by the control output circuit  16 , and connected to the connecting terminal PIN via the driving circuit  22  and divided into a plurality of terminal sets, thereby using each terminal set for connecting to a decorative light module  3  (light string/light strip equipped with a plurality of LEDs arranged linearly) installed on each branch of a Christmas tree, such that each decorative light module  3  is able to receive an operation control of the main controller  1  via each one of the branch controllers  2 . 
     According to the aforementioned structure, wherein the main controller  1  further comprises: a timing circuit  13 , a memory circuit  14  and a RF remote control circuit  15  connected to the main control circuit  11  respectively, the RF remote control circuit  15  configured to receive a RF wireless control signal from external in order to form an operational command inputted into the main control circuit, the timing circuit  13  configured to be operable for adjusting a running time of the main control circuit  11 , the memory circuit  14  configured to store a control parameter of the built-in dimming control program of the main control chip U 1 . 
     According to the aforementioned structure, wherein the main controller  1  further comprises: an anti-reverse power source connection circuit  12  connected to the main control circuit  11 ; the anti-reverse power source connection circuit  12  comprising one three-terminal voltage regulator Q 7  and a diode D 5 ; the diode D 5  arranged between an input end of the three-terminal voltage regulator Q 7  and a main power source input end VDCin in a forward direction, such that when a polarity of an external power source connected to the main power source input end VDCin is correct, the diode D 5  is conducted in order to allow the three-terminal voltage regulator Q 7  to operate normally; on the contrary, when the polarity is incorrect, the diode D 5  is not conducted to prevent the power source from connecting to the three-terminal voltage regulator Q 7 . 
     According to the aforementioned structure, wherein the control output circuit  16  comprises a control chip U 4 , a resistor R 4  and an indicator lamp circuit  161 ; the control chip U 4  is an erasable programable read only memory (EPROM) with 16 pins, a fifth pin of the control chip U 4  is connected to the output end of the three-terminal voltage regulator Q 7  in order to provide a power source necessary for conduction; a sixth pin, a seventh pin, an eighth pin and a ninth pin of the control chip U 4  connected to a first pin, a fourteenth pin, a thirteenth pin and a twelfth pin of the main control chip U 1  respectively in order to receive the control signal outputted by the main control chip U 1 ; a tenth pin of the control chip U 4  is connected to an eighth pin of the main control chip U 1  via the resistor R 4 , a twelfth pin of the control chip U 4  is connected to a ground end GND; a thirteenth pin, a fourteenth pin, a fifteenth pin and a sixteenth pin of the control chip U 4  are jointly connected to a main control signal output end Scon in order to output the main control signal for controlling the branch controller  2 ; the indicator lamp circuit  161  comprises four indicator lamps D 1 , D 2 , D 3 , D 4 , wherein two of the indicator lamps D 1 , D 2  are connected to each other in a forward-reverse parallel manner, and one end thereof is connected to a first pin of the control chip U 4 , the other two indicator lamps D 3 , D 4  are connected to each other in a forward-reverse parallel manner, and one end thereof is connected to a second pin of the control chip U 4 , another end of the four indicator lamps D 1 , D 2 , D 3 , D 4  is connected to a third pin of the control chip U 4  jointly via a resistor R 2 , such that the timing circuit  13  is able to set various timing periods for the indicator lamps D 1 , D 2 , D 3 , D 4  via the first pin, the second pin and third pin of the control chip U 4  and the resistor R 2 . 
     According to the aforementioned structure, wherein the main power source input end VDCin is connected to an external AC power source via a power source module  10 , such that the AC power source is converted to a DC power source of DC5V-36V via the power source module  10 , and further connected to the main power source input end VDCin. 
     According to the aforementioned structure, wherein the main control chip U 1  is an erasable programable read only memory (EPROM) with 14 pins; a tenth pin of the main control chip U 1  is connected to an output end of the three-terminal voltage regulator Q 7  via a resistor R 3 , and the tenth pin of the main control chip U 1  is further connected to the ground end GND via a switch K 1 . 
     According to the aforementioned structure, wherein the timing circuit  13  includes two capacitors C 1 , C 2  and a crystal oscillator JZ 1 , two ends of the crystal oscillator JZ 1  are connected to a fifth pin and a sixth pin of the main control chip U 1  respectively, and the two ends of the crystal oscillator are further connected to the ground end GND via the two capacitors C 1 , C 2 . 
     According to the aforementioned structure, wherein the memory circuit  14  comprises a storage chip U 2  with 8 pins and a resistor R 1 , an eighth pin of the storage chip U 2  is connected to the output end of the three-terminal voltage regulator Q 7 , and the eighth pin of the storage chip U 2  is further connected to a third pin of the main control chip U 1  and a fifth pin of the storage chip U 2  respectively via the resistor R 1 , a sixth pin of the storage chip U 2  is connected to a second pin of the main control chip U 1 , and a fourth pin of the storage chip U 2  is connected to the ground end GND. 
     According to the aforementioned structure, wherein the RF remote control circuit  15  comprises a radio frequency integrated circuit chip U 3  with 8 pins, two chip inductors L 1 , L 2 , five capacitors C 4 , C 5 , C 6 , C 7 , C 8 , a crystal oscillator JZ 2  and an antenna AT; a first pin and a sixth pin of the radio frequency integrated circuit chip U 3  are jointly connected to the ground end GND; a second pin and a third pin of the radio frequency integrated circuit chip U 3  are jointly connected to the output end of the three-terminal voltage regulator Q 7  and also jointly connected to one end of the two capacitors C 4 , C 6  and to one end of the chip inductor L 1 , another end of the capacitor C 4  is respectively connected to one end of the capacitor C 5 , one end of the chip inductor L 2  and the antenna AT, another end of the capacitor C 6 , another end of the chip inductor L 1 , another end of the chip inductor L 2  and another end of the capacitor C 5  are jointly connected to the ground end GND respectively, a fourth pin of the radio frequency integrated circuit chip U 3  is grounded via the capacitor C 7 , a fifth pin of the radio frequency integrated chip U 3  is connected to a seventh pin of the main control chip U 1 , a seventh pin of the radio frequency integrated circuit chip U 3  is grounded via the capacitor C 8 , an eighth pin of the radio frequency integrated circuit chip U 3  is connected to the ground end GND via the crystal oscillator JZ 2 . 
     According to the aforementioned structure, wherein the signal transmission circuit  21  comprises: a plurality signal transmission chips U 5 , U 6 , U 7 , U 8  connected in series, a plurality of resistors R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 , R 22 , a plurality of capacitors C 10 , C 11 , C 12 , C 13 ; each one of the signal transmission chips U 5 , U 6 , U 7 , U 8  is a single-wire transmission three-channel LED driver control chip with 8 pins; a first pin, a second pin and a third pin of the signal transmission chip U 8  are respectively connected to a branch power source input end V+ in sequence via the resistors R 18 , R 19 , R 20 ; a fourth pin of the signal transmission chip U 8  is directly connected to the ground end GND, a fifth pin of the signal transmission chip U 8  is connected to a sixth pin of the signal transmission chip U 7  via the resistor R 16 ; the sixth pin of the signal transmission chip U 8  is connected to a branch control signal input end Sin via the resistor R 21 ; the branch control signal input end Sin is configured to receive the main control signal outputted by the main controller  1 ; an eighth pin of the signal transmission chip U 8  is connected to the branch power source input end V+ via the resistor R 22 ; the branch power source input end V+ is configured to receive a power source provided by the main controller  1 , and the capacitor C 13  is arranged between the first pin and the eighth pin of the signal transmission chip U 8 ; a first pin, a second pin and a third pin of the signal transmission chip U 7  are respectively connected to the branch power source input end V+ in sequence via the resistors R 13 , R 14 , R 15 ; a fourth pin of the signal transmission chip U 7  is directly connected to the ground end GND; a fifth pin of the signal transmission chip U 7  is connected to a sixth pin of the signal transmission chip U 6  via the resistor R 12 ; an eighth pin of the signal transmission chip U 7  is connected to the branch power source input end V+ via the resistor R 17  in order to conduct to a power source required, and the capacitor C 12  is arranged between the first pin and the eighth pin of the signal transmission chip U 7 ; a first pin, a second pin and a third pin of the signal transmission chip U 6  are respectively connected to the branch power source input end V+ in sequence via the resistors R 9 , R 10 , R 11  in order to conduct to a power source required; a fourth pin of the signal transmission chip U 6  is directly connected to the ground end GND; a fifth pin of the signal transmission chip U 6  is connected to a sixth pin of the signal transmission chip U 5  via the resistor R 8 , and the capacitor C 11  is arranged between the first pin and the eighth pin of the signal transmission chip U 6 ; a first pin, a second pin and a third pin of the signal transmission chip U 5  are respectively connected to the branch power source input end V+ in sequence via the resistors R 5 , R 6 , R 7  in order to conduct to a power source required; a fourth pin of the signal transmission chip U 5  is directly connected to the ground end GND; the fifth pin of the signal transmission chip U 5  is connected to a branch control signal output end Sout; the branch control signal output end Sout is configured to be connected to another branch controller  2  and to provide a control signal required; the capacitor C 10  is arranged between the first pin and the eighth pin of the signal transmission chip U 5 . 
     According to the aforementioned structure, wherein the driving circuit  22  comprises: a plurality driving chips U 9 , U 10 , U 11 , U 12 , U 13 , a plurality of resistors R 23 , R 24 , R 25 , R 26 , R 27 ; each one of the driving chips U 9 , U 10 , U 11 , U 12 , U 13  is a two-way driving control chip with 8 pins; first pins of the driving chips U 9 , U 10 , U 11 , U 12 , U 13  are respectively connected to a branch power source input end V+ in order to conduct to a power source required; third pins and seventh pins of the driving chips U 9 , U 10 , U 11 , U 12 , U 13  are respectively connected to a ground end GND; a second pin and a fourth pin of the driving chip U 13  are connected to a first pin and a second pin of the connecting terminal PIN via the resistor R 27  in order to form a first terminal set provided for connecting to each one of the decorative light modules  3 ; a fifth pin and an eighth pin of the driving chip U 13  are respectively connected to a first pin and a second pin of the signal transmission chip U 8 , thereby receiving signals from the signal transmission chip U 8  to drive the decorative light module  3  connected to the first terminal set of the connecting terminal PIN; a second pin and a fourth pin of the driving chip U 12  are connected to a third pin and a fourth pin of the connecting terminal PIN via the resistor R 26  in order to form a second terminal set provided for connecting to each one of the decorative light modules  3 ; a fifth pin of the driving chip U 12  is connected to a third pin of the signal transmission chip U 8 , an eighth pin of the driving chip U 12  is connected to a first pin of the signal transmission chip U 7 , thereby receiving signals from the signal transmission chips U 7 , U 8  respectively in order to drive the decorative light module  3  connected to the second terminal set of the connecting terminal PIN; a second pin and a fourth pin of the driving chip U 11  are connected to a fifth pin and a sixth pin of the connecting terminal PIN via the resistor R 25  in order to form a third terminal set provided for connecting to each one of the decorative light modules  3 ; a fifth pin and an eighth pin of the driving chip U 11  are respectively connected to a second pin and a third pin of the signal transmission chip U 7 , thereby receiving signals from the signal transmission chip U 7  in order to drive the decorative light module  3  connected to the third terminal set of the connecting terminal PIN; a second pin and a fourth pin of the driving chip U 10  are connected to a seventh pin and an eighth pin of the connecting terminal PIN via the resistor R 24  in order to form a fourth terminal set provided for connecting to each one of the decorative light modules  3 ; a fifth pin and an eighth pin of the driving chip U 10  are respectively connected to a second pin and a third pin of the signal transmission chip U 6 , thereby receiving signals from the signal transmission chip U 6  in order to drive the decorative light module  3  connected to the fourth terminal set connected to the connecting terminal PIN; a second pin and a fourth pin of the driving chip U 9  are connected to a ninth pin and a tenth pin of the connecting terminal PIN via the resistor R 23  in order to form a fifth terminal set provided for connecting to each one of the decorative light modules  3 ; a fifth pin and an eighth pin of the driving chip U 9  are respectively connected to a first pin and a second pin of the signal transmission chip U 5 , thereby receiving signals from the signal transmission chip U 5  in order to drive the decorative light module  3  connected to the fifth terminal set of the connecting terminal PIN. 
     In comparison of the currently existing techniques, the advantages of the present invention include: 
     1. One single main controller is used to connect to and to control a plurality of branch controllers, and each branch controller is further connected to and controlling a plurality of decorative light modules respectively, thereby creating a completely modularized and integrated structure. Therefore, the overall wiring structure and construction procedure can be simplified. In addition, since each decorative light module has its independent wiring, in case of any malfunction, the connection portion of the decorative light module and its branch controller can be identified easily and swiftly in order to perform repair or replacement of the damaged decorative light module without any changes or adjustments to other decorative light modules. As a result, the repair procedure is simplified and the cost of use is reduced. 
     2. For the main controller, the quantity of the branch controllers can be additionally increased depending upon the needs directly. In addition, with the increase of the quantity of the branch controllers, the quantity of the decorative light module connected thereto can be increased. Furthermore, since all of the decorative light modules are jointly connected to and controlled by the main controller, during the use, the overall scale of the decorative light can be expanded depending upon the customized needs; as a result, it can have a relatively broader applicable scope. 
     3. The main controller includes an anti-reverse power source connection circuit capable of preventing reverse connection of power source, a memory circuit capable of storing control parameters operated and a RF remote circuit capable of remotely operating the main controller from the external, such that the convenience and safety of use are increased. 
     To further explain the aforementioned objectives, technical effects and characteristics of the present invention, please refer to the illustrations of the following accompanied drawings: 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG. 1  is a block diagram of the main circuit structure of the present invention; 
         FIG. 2  is a circuit diagram of the main controller of the present invention; 
         FIG. 3  is a circuit diagram of the branch controller of the present invention; and 
         FIG. 4  is a circuit diagram illustrating the main controller connected to a plurality of branch controllers with each other of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Please refer to  FIG. 1  to  FIG. 3 . From the drawings, it can be understood that the structure of the present invention mainly comprises: a controller  1 , at least one branch controller  2  and a plurality decorative light modules  3  (light string/light strip equipped with a plurality of LEDs arranged linearly); wherein the main controller  1  is mainly formed by a main control circuit  11 , an anti-reverse power source connection circuit  12 , a timing circuit  13 , a memory circuit, a RF remote control  15  and a control output circuit  16 . 
     The anti-reverse power source connection circuit  12  includes a three-terminal voltage regulator Q 7 , a capacitor C 3  and a diode D 5 ; wherein the capacitor C 3   s  arranged between the output end (third pin) of the three-terminal voltage regulator Q 7  and the ground end GND (second pin), the diode D 5  is arranged between the input end (first pin) of the three-terminal voltage regulator Q 7  and a main power source input end VDCin in a forward direction. When the polarity of the external power source connected to the main power source input end VDCin is correct, the diode D 5  is conducted in order to allow the three-terminal voltage regulator Q 7  to operate normally. On the contrary, if the polarity is incorrect, the diode D 5  is not conducted to prevent the power source from connecting to the three-terminal voltage regulator Q 7 , such that the protection effect capable of preventing the main control chip U 1  from being punctured can be achieved. 
     During the actual application, if a conventional grid AC power source (AC 100-240V) is used, then the AC power source can pass through a power source module  10  (power adapter) for rectification and filter in order to convert it into a DC power source (DC 5V-36V), followed which the main power source input end VDCin is connected to the main controller  1  for conduction. The main power source input end VDCin can be directly connected to a main power source output end VDCout, and two ground ends GND connected to each other can be arranged at one side of the corresponding main power source input end VDCin and the main power source output end VDCout respectively. The main power source output end VDCout and the ground end GND can be used to form a branch power supply end capable of providing the power source necessary for the branch controller  2 . 
     The main control circuit  11  includes a main control chip U 1 , a resistor R 3  and a switch K 1 ; wherein the main control chip U 1  is an erasable programable read only memory (EPROM) with 14 pins and equipped with a built-in dimming function in order to control and generate various different lighting modes via a built-in control program (the use of a control program in the main control chip U 1  is an a known technique commonly used). The fourth pin of the main control chip U 1  is connected to the output end (third pin) of the three-terminal voltage regulator Q 7  in order to conduct a working voltage of DC 36V. The resistor R 3  is arranged between the fourth pin and the tenth pin of the main control chip U 1 , and the tenth pin of the main control chip U 1  is grounded via the switch K 1 . 
     The timing circuit  13  includes: two capacitors C 1 , C 2  and a crystal oscillator JZ 1 ; wherein two ends of the crystal oscillator are connected to the fifth pin and the sixth pin of the main control chip U 1  respectively, and the two ends of the crystal oscillator JZ 1  are further grounded via the capacitors C 1 , C 2  respectively, thereby forming a timing mechanism connected to the main control chip U 1 . 
     The memory circuit  14  comprises a storage chip U 2  with 8 pins and a resistor R 1 ; wherein the eighth pin of the storage chip U 2  is connected to the output end (third pin) of the three-terminal voltage regulator Q 7  in order to connect to the required power source. In addition, the eighth pin of the storage chip U 2  is jointly connected to the third pin of the main control chip U 1  and the fifth pin of the storage pin U 2  via the resistor R 1 , the sixth pin of the storage chip U 2  is connected to the second pin of the main control chip U 1 , and the fourth pin of the storage chip U 2  is grounded. Accordingly, the storage chip U 2  is able to store various operational setting parameters of the main control chip U 1 , and during the restoration of power supply after power shutdown, it is able to recover various functions already set before the power shutdown. 
     The RF remote control circuit  15  comprises a radio frequency integrated circuit chip U 3  with 8 pins, two chip inductors L 1 , L 2 , capacitors C 4 , C 5 , C 6 , C 7 , C 8 , a crystal oscillator JZ 2  and an antenna AT; wherein the first pin and the sixth pin of the radio frequency integrated circuit chip U 3  are grounded jointly, the second pin and third pin of the radio frequency integrated circuit chip U 3  are jointly connected to the output end (third pin) of the three-terminal voltage regulator Q 7  and are also jointly connected to one end of the capacitors C 4 , C 6  and the chip inductor L 1 ; another end of the capacitor C 4  is connected to one end of the capacitor C 5 , one end of the chip inductor L 2  and the antenna AT respectively; another end of the capacitor C 6  is respectively connected to another end of the chip inductor L 1 , another end of the chip inductor L 2 , another end of the capacitor C 5  and jointly connected to the ground; the fourth pin of the radio frequency integrated circuit chip U 3  is grounded via the capacitor C 7 ; the fifth pin of the radio frequency integrated circuit chip U 3  is connected to the seventh pin of the main control chip U 1 ; the seventh pin of the radio frequency integrated circuit chip U 3  is grounded via the capacitor C 8 ; the eighth pin of the radio frequency integrated circuit chip U 3  is grounded via the crystal oscillator JZ 2 . Accordingly, after the antenna AT receives an external RF control remote signal, the signal is amplified via the chip inductors L 1 , L 2  and the capacitors C 4 , C 5 , C 6 , following which it is inputted into the radio frequency integrated circuit chip U 3 . After the signal is converted into an operational command by the radio frequency integrated circuit chip U 3 , it is transmitted to the main control chip U 1  to perform the subsequent control and adjustment actions. 
     The control output circuit  16  includes a control chip U 4 , a resistor R 4  and an indicator lamp circuit  161  connected to the control chip U 4 . The control chip U 4  is an erasable programable read only memory (EPROM) with 16 pins, and its fifth pin is connected to the output end (third pin) of the three-terminal voltage regulator Q 7  in order to conduct the required power source. The sixth pin, seventh pin, eighth pin and ninth pin of the control chip U 4  are respectively connected to the first pin, fourteenth pin, thirteenth pin and twelfth pin of the main control chip U 1  in order to receive the control signal outputted by the main control chip U 1 . The tenth pin of the control chip U 4  is connected to the eighth pin of the main control chip U 1  via the resistor R 4 , and the twelfth pin of the control chip U 4  is grounded. The thirteenth pin, the fourteenth pin, fifteenth pin and sixteenth pin of the control chip U 4  are jointly connected to a main control signal output end Scon in order to provide a main control signal necessary for the subsequent actions of the branch controller  2 . 
     The indicator lamp circuit  161  comprises: two indicator lamps D 1 , D 2  (can be LEDs) connected in a forward-reverse parallel manner and having one end connected to the first pin of the control chip U 4  respectively, two indicator lamps D 3 , D 4  (can be LEDs) connected in a forward-reverse parallel manner and having one end connected to the second pin of the control chip U 4  respectively. Other ends of the indicator lamps D 1 , D 2 , D 3  and D 4  are jointly connected to the third pin of the control chip U 4  via the resistor R 2 , thereby allowing the timing circuit  13  to set various timing periods for the indicator lamps D 1 , D 2 , D 3  and D 4  via the first pin, second pin, third pin of the control chip U 4  and the resistor R 2 . 
     The branch controller  2  comprises: a signal transmission circuit  21  and a driving circuit  22 ; wherein the signal transmission circuit  21  includes a plurality of signal transmission chips U 5 , U 6 , U 7 , U 8  connected in series, resistors R 5 ˜R 22  and capacitors C 10 ˜C 13 . 
     The first pin, second pin and the third pin of the signal transmission chip U 8  are directly connected to a branch power source input end V+ via the resistors R 18 , R 19 , R 20  respectively in sequence, and the fourth pin of the signal transmission chip U 8  is directly connected to a ground end GND. The fifth pin of the signal transmission chip U 8  is connected to the sixth pin of the signal transmission chip U 7  via the resistor R 16 . The sixth pin of the signal transmission chip U 8  is connected to a branch control signal input end Sin via the resistor R 21 , and the branch control signal input end Sin is connected to the main control signal output end Scon of the main controller  1  in order to receive the main control signal outputted from the main controller  1 . The eighth pin of the signal transmission chip U 8  is connected to the branch power source input end V+ via the resistor R 22 , and the branch power source input end V+ is connected to the main power source output end VDCout (branch power supply end) of the main controller  1  in order to receive the power supplied from the main controller  1 . In addition, the capacitor C 13  is arranged between the first pin and the eighth pin of the signal transmission chip U 8 . 
     The first pin, second pin and the third pin of the signal transmission chip U 7  are respectively connected to the branch power source input end V+ in sequence via the resistors R 13 , R 14 , R 15 . The fourth pin of the signal transmission chip U 7  is directly connected to the ground end GND. The fifth pin of the signal transmission chip U 7  is connected to the sixth pin of the signal transmission chip U 6  via the resistor R 12 . The eighth pin of the signal transmission chip U 7  is connected to the branch power source input end V+ via the resistor R 17  in order to conduct the required power source. In addition, the capacitor C 12  is arranged between the first pin and the eighth pin of the signal transmission chip U 7 . 
     The first pin, second pin and third pin of the signal transmission chip U 6  are respectively connected to the branch power source input end V+ in sequence via the resistors R 9 , R 10 , R 11  in order to conduct the required power source. The fourth pin of the signal transmission chip U 6  is directly connected to the ground end GND. The fifth pin of the signal transmission chip U 6  is connected to the sixth pin of the signal transmission chip U 5  via the resistor R 8 . The capacitor C 11  is arranged between the first pin and the eighth pin of the signal transmission chip U 6 . 
     The first pin, second pin and third pin of the signal transmission chip U 5  are respectively connected to the branch power source input end V+ in sequence via the resistors R 5 , R 6 , R 7  in order to conduct the required power source. The fourth pin of the signal transmission chip U 6  is directly connected to the ground end GND. The fifth pin of the signal transmission chip U 6  is connected to a branch control signal output end Sout. The branch control signal output end Sout is configured to be connected to another branch controller  2  and to provide a control signal required. The capacitor C 10  is arranged between the first pin and the eighth pin of the signal transmission chip U 5 . 
     The driving circuit  22  includes: driving chips U 9 ˜U 13 , resistors R 23 ˜R 27  and a connecting terminal PIN. The first pins of the driving chips U 9 , U 10 , U 11 , U 12 , U 13  are connected to the branch power source input end V+ respectively in order to conduct the power source required. The third pin and seventh pin of the driving chips U 9 , U 10 , U 11 , U 12 , U 13  are connected to the ground end GND respectively. 
     The second pin and fourth pin of the driving chip U 13  are connected to the first pin and second pin of the connecting terminal PIN via the resistor R 27  in order to form a first terminal set provided for connecting to an external decorative light modules  3  (LED light string/light strip). The fifth pin and eighth pin of the driving chip U 13  are connected to the first pin and the second pin of the signal transmission chip U 8  in order to receive signals from the signal transmission chip U 8  and to control the decorative light module  3  connected to the first terminal set (first pin and second pin) of the connecting terminal PIN. 
     The second pin and fourth pin of the driving chip U 12  are connected to a third pin and a fourth pin of the connecting terminal PIN via the resistor R 26  in order to form a second terminal set provided for connecting to an external decorative light modules  3  (LED light string/light strip). The fifth pin of the driving chip U 12  is connected to the third pin of the signal transmission chip U 8 . The eighth pin of the driving chip U 12  is connected to the first pin of the signal transmission chip U 7 , thereby receiving signals from the signal transmission chips U 7 , U 8  respectively in order to drive the decorative light module  3  connected to the second terminal set (third pin and fourth pin) of the connecting terminal PIN. 
     The second pin and fourth pin of the driving chip U 11  are connected to the fifth pin and sixth pin of the connecting terminal PIN via the resistor R 25  in order to form a third terminal set provided for connecting to an external decorative light modules  3  (LED light string/light strip). The fifth pin and eighth pin of the driving chip U 11  are respectively connected to the second pin and third pin of the signal transmission chip U 7  in sequence, thereby receiving signals from the signal transmission chip U 7  in order to control the decorative light module  3  connected to the third terminal set (fifth pin and sixth pin) of the connecting terminal PIN. 
     The second pin and fourth pin of the driving chip U 10  are connected to the seventh pin and eighth pin of the connecting terminal PIN via the resistor R 24  in order to form a fourth terminal set provided for connecting to an external decorative light module  3  (LED light string/light strip). The fifth pin and eighth pin of the driving chip U 10  are respectively connected to the second pin and third pin of the signal transmission chip U 6  in sequence, thereby receiving signals from the signal transmission chip U 6  in order to control the decorative light module  3  connected to the fourth terminal set (seventh pin and eighth pin) connected to the connecting terminal PIN. 
     The second pin and fourth pin of the driving chip U 9  are connected to the ninth pin and tenth pin of the connecting terminal PIN via the resistor R 23  in order to form a fifth terminal set provided for connecting to an external decorative light modules  3  (LED light string/light strip). The fifth pin and eighth pin of the driving chip U 9  are respectively connected to the first pin and second pin of the signal transmission chip U 5  in sequence, thereby receiving signals from the signal transmission chip U 5  in order to drive the decorative light module  3  connected to the fifth terminal set (ninth pin and tenth pin) of the connecting terminal PIN. 
     Through the aforementioned connection method of connecting each one of the signal transmission chips U 5 , U 6 , U 7 , U 8  with each other, the main control signal inputted by the branch control signal input end Sin can be inputted from the fifth pin of the signal transmission chip U 8 , followed by respectively transmitting to the signal transmission chips U 7 , U 6 , U 5  in sequence. Then, the driving circuit  22  is able to drive each set of the decorative light modules  3  connected to the connecting terminal PIN respectively. 
     As shown in  FIG. 4 , it can be understood that during the actual application of the aforementioned structure of the present invention, a plurality of branch controllers  2  of an appropriate quantity can be installed according to the energy supplied by the power supply and the demanded quantity of the decorative light modules  3  (LED light strings/light strips) desired to be installed on each tree branch of the Christmas tree, such that each of the decorative light modules  3  is connected to each one of the branch controller  2  respectively, following which a main controller  1  is used for connecting to the plurality of branch controllers  2  in series in order to control such branch controllers. The configuration method is as follows: 
     The main power source output end VDCout (branch power supply end) of the main controller  1  is connected to the branch power source input end V+ of each one of the branch controller  2  respectively, and the ground end GND of the main controller  1  is connected to the ground end GND of each one of the branch controllers  2  respectively, in order to provide the power source necessary for each one of the branch controllers  2 . The main control signal output end Scon of the main controller  1  is connected to the branch control signal input tend Sin of one of the branch controllers  2  (referred to as the first branch controller  2 ), in order to transmit a main control signal outputted by the main controller  1  to the (first) branch controller  2 . At the same time, the branch control signal output end Sout of the (first) branch controller  2  is connected to the branch control signal input end Sin of another branch controller  2  (referred to as the second branch controller  2 ). Consequently, through such connection method of connecting the branch control signal output end Sout of different branch controller  2  to another branch control signal input end Sin, a decorative light structure having one single main controller  1  connected to and controlling a plurality of light decorative modules  3  (LED light strings/light strips) via a plurality of branch controllers  2  can be assembled and achieved. 
     In the aforementioned structure of the present invention, each branch controller  2  can use the connecting terminal PIN for connecting to a plurality of decorative light modules  3  (LED light strings/light strips) installed on each tree branch, and the quantity of the branch controllers  2  and the quantities of the signal transmission circuits  21  and driving circuits  22  in each branch controller  2  can be expanded depending upon the actual condition. The control output circuit  16  of the main controller  1  sends out the main control signal via the main control signal output end Scon, and the signal transmission circuit  21  of a branch controller  2  then receives the main control signal via the branch control signal input end Sin, and the signal is further transmitted to the driving circuit  22 . The driving circuit  22  then uses different driving chips U 9 ˜U 13  to jointly control the actions of the light decorative modules  3  via the connecting terminal PIN. Accordingly, with such structure, each one of the decorative light modules  3  on each one of the tree branches of the Christmas tree can be prevented from interfering with each other, and during any malfunction, inspection and repair can be performed easily. Furthermore, the light decorative modules  3  on different tree branches can also have their own independent wiring during the installation, followed by integrating the circuits together onto the connecting terminal PIN of the branch controller  2 . Finally, all of the branch controllers  2  are connected to a main controller  1  in order to allow the main controller  1  to perform uniform control, and the overall circuits are neatly arranged.