Patent Publication Number: US-2019180924-A1

Title: Coil module, filter module and power module

Description:
REFERENCE TO RELATED APPLICATION 
     This application claims priority benefit of Taiwan Application Serial Number 106143601, filed Dec. 12, 2017. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of specification. 
     BACKGROUND 
     Technical Field 
     The present application relates to a device. More particularly, the present application relates to a coil module, a filter module, and a power module. 
     Related Art 
     The voltage generated by the AC/DC power circuit is equivalent to the voltage ripples or is equivalent to a rapid voltage change of the system terminals. The interference may be coupled into other circuits due to the stray capacitance, thereby causing the common mode problems. In the prior art, the small LC filter is used to remove noise. As shown in  FIG. 1 , the small LC filter is composed of a normal inductor L and a normal capacitor C. 
     In the related art, the small LC filters are not effective to suppress the conducted interference, thereby causing the serious interference between the RF circuit and other circuits. It is important to effectively suppress the conducted interference between the communication devices and ICs of various applications. 
     SUMMARY 
     The present application discloses a coil module, a filter module, and a power module. 
     In one embodiment of the application, a coil module comprises a ring core, a first coil and a second coil. The first coil and the second coil are wound around both sides of the ring core in a symmetrical manner. The first coil and the second coil are disconnected from each other. 
     In another embodiment of the application, a filter module comprises a capacitor, a first coil module, and a second coil module. The first coil module and the second coil module are connected to two ends of the capacitor in a symmetrical manner. 
     In one embodiment of the application, a power module comprises an AC power input module, a switching mode high frequency DC power module, a filter module, and a DC output module. The switching mode high frequency DC power module is electrically connected to the AC power input module. The filter module comprising a capacitor, a first coil module, and a second coil module. The first coil module and the second coil module are electrically connected to two ends of the capacitor. The first coil module is electrically connected to the switching mode high frequency DC power module. The DC output module is electrically connected to the second coil module of the filter module. The DC output module outputs DC power to a system terminal module. 
     To sum up, the technical solution of the present application has apparent advantages and beneficial effects in comparison with the prior art. By the technical solution of the present application, the noise transmitting by the DC power can effectively prevent. 
     The foregoing description is described in detail below with reference to the implementation manners, and the technical solutions of the present application are further explained. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to let above mention of the present application and other objects, features, advantages, and embodiments of the present application to be more easily understood, the description of the accompanying drawing as follows: 
         FIG. 1  illustrates a circuit diagram of a small LC filter in prior art. 
         FIG. 2A  illustrates a front view of a coil module according to one embodiment of the present application. 
         FIG. 2B  illustrates a side view of the coil module according to one embodiment of the present application. 
         FIG. 3  illustrates a perspective view of a coil module according to another embodiment of the present application. 
         FIG. 4  illustrates a side view of a filter module according to one embodiment of the present application. 
         FIG. 5  illustrates a block diagram of a power module according to one embodiment of the present application. 
         FIG. 6  illustrates a noise spectrum diagram of a power module using the small LC filter in  FIG. 1 . 
         FIG. 7  illustrates a noise spectrum diagram of the power module in  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Reference may be made to the accompanying drawings and various embodiments described below in order to make the application more complete and detailed. The same symbols among the different drawing indicate the same or similar elements. On the other hand, known components and steps are not described in detail in the embodiments to avoid unnecessary limitation of the application. 
       FIG. 2A  illustrates a front view of a coil module according to one embodiment of the present application. As shown in  FIG. 2A , the coil module includes a first coil  210 , a second coil  220 , and a ring core  230 . In structure, the first coil  210  and the second coil  220  are wound around both sides of the ring core  230  in a symmetrical manner. The first coil  210  and the second coil  220  are disconnected from each other. It should be understood that the first coil  210  and the second coil  220  are wound around the same ring core  230  instead of being wound around different winding slots, thereby reducing the stray capacitance and reducing the volume. 
     In practice, the first coil  210  and the second coil  220  are both conducting wires. The number of turns of the first coil  210  is the same as the number of turns of the second coil  220 , such as 10 to 20 turns, thereby effectively suppressing the low frequency noise. The first coil  210  and the second coil  220  are spaced apart by a predetermined distance d, thereby forming two inductors. The predetermined distance d may be 5 to 10 mm. The coil module further includes a fixed member  240 . The fixed member  240  is attached to the first coil  210 , the second coil  220 , and the inner edge of the ring core  230  between the first coil  210  and the second coil  220 , so that the positions of the first coil  210  and the second coil  220  on the ring core  230  are fixed. In one embodiment, the fixed member  240  may be epoxy or other suitable material. 
     An end  211  of the first coil  210  and an end  221  of the second coil  221  may extent to connect a circuit board, such as the circuit board  401  shown in  FIG. 4 . 
       FIG. 2B  illustrates a side view of the coil module according to one embodiment of the present application. As shown in  FIG. 2B , the end  221  of the second coil  220  has two terminal  222  and  223  to electrically connect to different circuit components (such as the capacitors and the DC modules), respectively. Since the second coil  220  is symmetrical to the first coil  210 , the end  211  of the first coil  210  also has two terminals  212  and  213 , as shown in  FIG. 3 . 
       FIG. 3  illustrates a perspective view of a coil module according to another embodiment of the present application. The coil module of  FIG. 3  is substantially identical to the coil module of  FIGS. 2A and 2B  except that the structure of the coil module of  FIG. 3  is that the returned winding should be crossed to the gap. Specifically, the first coil  210  includes a first partial winding  301  and a second partial winding  302  connected to each other. The first partial winding  301  forms a layer of winding wound around a periphery of one side of the ring core  230 , and the second partial winding  302  is returned back and interleaved with the first partial winding  301  to fill the gap on the side of the ring core  230  which is not wound by the first partial winding  301 , thereby increasing the inductance. Similarly, the second coil  220  includes a third partial winding  303  and a fourth partial winding  304  connected to each other. The third partial winding  303  forms a layer of winding wound around a periphery of the other side of the ring core  230 , and the fourth partial winding  304  is returned back and interleaved with the third partial winding  303 , thereby increasing the inductance. 
       FIG. 4  illustrates a side view of a filter module according to one embodiment of the present application. As shown in  FIG. 4 , the filter module includes a capacitor C 1 , a first coil module L 1 , and a second coil module L 2 . In structure, the first coil module L 1  and the second coil module L 2  are connected to two ends of the capacitor C 1  in a symmetrical manner. 
     The first coil module L 1  includes a first coil  410 , a second coil  420 , and a first ring core  430 . The first coil  410  and the second coil  420  are wound around both sides of the first ring core  430  in a symmetrical manner. The first coil  410  and the second coil  420  are disconnected from each other. In one embodiment, the structure of the first coil  410 , the second coil  420 , and the first ring core  430  is substantially identical to the abovementioned structure of the first coil  210 , the second coil  220 , and the ring core  230 , and is not repeated here. 
     The second coil module L 2  includes a third coil  410 ′, a fourth coil  420 ′, and a second ring core  430 ′. The third coil  410 ′ and the fourth coil  420 ′ are wound around both sides of the second ring core  430 ′ in a symmetrical manner. The third coil  410 ′ and the fourth coil  420 ′ are disconnected from each other. In one embodiment, the structure of the third coil  410 ′, the fourth coil  420 ′, and the second ring core  430 ′ is substantially identical to the abovementioned structure of the first coil  210 , the second coil  220 , and the ring core  230 , and is not repeated here. 
     As shown in  FIG. 4 , the filter module further includes a circuit board  401  and a block piece  402 . The capacitor C 1 , the first coil module L 1 , and the second coil module L 2  are disposed on the circuit board  401 . The block piece  402  is erected on the circuit board  402 . A height of the block piece  402  is greater than a height of any one of the capacitor C 1 , the first coil module L 1 , and the second coil module L 2 , thereby preventing the cover or other components to be pressed the first coil module L 1  or the second coil module L 2 . In one embodiment, the block piece  402  may be a rigid plastic tube or other suitable components. 
       FIG. 5  illustrates a block diagram of a power module according to one embodiment of the present application. As shown in  FIG. 5 , the power module includes an AC power input module  510 , a switching mode high frequency DC power module  520 , a filter module  530 , and a DC output module  540 . 
     In structure, the switching mode high frequency DC power module  520  is electrically connected to the AC power input module  510 . The filter module  530  includes a capacitor C 1 , a first coil module L 1 , and a second coil module L 2 . The first coil module L 1  and the second coil module L 2  are connected to two ends of the capacitor C 1 . The first coil module L 1  is electrically connected to the switching mode high frequency DC power module  520 . The DC output module  540  is electrically connected to the second coil module L 2  of the filter module  530 . The DC output module  540  outputs DC power to a system terminal module  550 . 
     In practice, the AC power input module  510  may be a universal input port, and the switching mode high frequency DC power module  520  may be a full-bridge AC/DC converter circuit, and the DC output module  540  may be a DC/DC converter circuit, and the system terminal module  550  may be a wireless system terminal module (such as a RF circuit, a WiFI module, etc.). 
     The capacitor C 1  may be an electrolytic capacitor. The electric material of the electrolytic capacitor is a dense oxide film formed by the surface of the anode metal material. The cathode material of the electrolytic capacitor is an electrolyte. At the same volume, the electrolytic capacitor may obtain much larger capacitance than the normal capacitor. 
     In a comparative example, if the filter module  530  of the power module is replaced by the small LC filter, the noise spectrum diagram of the power module is shown in  FIG. 6 , and the noise of the low frequency region (about 0.15 to 10 MHz) is very high. 
     In present embodiment, the noise spectrum diagram of the power module using the filter module  530  is shown in  FIG. 7 . Compared with  FIG. 6 , the noise of the low frequency region (about 0.15 to 10 MHz) is significant reduced. Therefore, the filter module  530  may effectively suppress the conducted interference transmitting to the system terminal module  550  (such as RF circuit) and serious interference causing between the system terminal module  550  and several different DC circuits (i.e., the switching mode high frequency DC power module  520  and the DC output module  540 ). 
     To sum up, the technical solution of the present application has apparent advantages and beneficial effects in comparison with the prior art. By the technical solution of the present application, the noise transmitting by the DC power can effectively prevent. 
     Although above DETAILED DESCRIPTION discloses the specific embodiment of the present application. However, it is not used to limit the present application. Those skilled in the art can make various changes and modifications of the present application without departing from the principle and spirit of the present application. Therefore, the scope of the present application should refer to the following claims.