CN217037409U - Single-directional noise reduction microphone - Google Patents

Abstract

The utility model discloses a unidirectional noise reduction microphone, which relates to the technical field of microphones and comprises a shell with an opening at one end, wherein a circuit board is arranged at the opening end of the shell, a shell sound hole is arranged at the sealing end of the shell, and a circuit board sound hole is arranged on the circuit board; a vibrating diaphragm is arranged on the inner side of the sealed end of the shell, a back plate and an insulating ring are arranged on the vibrating diaphragm, a first copper ring is arranged on the back plate, a damping component is arranged on the first copper ring, a second copper ring is arranged on the damping component, and the circuit board is arranged on the second copper ring and the insulating ring; a noise reduction circuit is arranged on the circuit board; the circuit board sound holes are metalized holes. The unidirectional noise reduction microphone solves the technical problem of poor noise reduction effect of an electret microphone in the prior art, and has the advantages of good noise reduction effect, strong anti-interference capability, no noise of output sound signals and good definition.

Description

Single-directional noise reduction microphone

Technical Field

The utility model relates to the technical field of microphones, in particular to a single-direction noise reduction microphone.

Background

Electret microphones are widely used in various electronic products because of their advantages such as stable performance, small distortion, and small size. With the continuous development of scientific technology, various mobile terminals with the functions of conversation and recording are more and more, and application scenes are more and more extensive, so that the working environment of the microphone is more and more complex, the noisy environment is more and more common, and great challenges are brought to the noise reduction capability and the anti-interference capability of the microphone. The conventional microphone at present is difficult to satisfy the noise reduction requirement under the complex environment, and the sound signal output by the microphone under the noisy environment has noise and poor definition.

Disclosure of Invention

In view of the above drawbacks, an object of the present invention is to provide a single directional noise reduction microphone, which has a good noise reduction effect, and outputs a sound signal without noise with good definition.

In order to achieve the purpose, the technical scheme of the utility model is as follows:

a single-direction noise reduction microphone comprises a shell with an open end, wherein a circuit board is arranged at the open end of the shell, a shell sound hole is formed in the sealed end of the shell, and a circuit board sound hole is formed in the circuit board; a vibrating diaphragm is arranged on the inner side of the sealed end of the shell, a back plate and an insulating ring are arranged on the vibrating diaphragm, a first copper ring is arranged on the back plate, a damping component is arranged on the first copper ring, a second copper ring is arranged on the damping component, and the circuit board is arranged on the second copper ring and the insulating ring; a noise reduction circuit is arranged on the circuit board; the circuit board sound hole is a metallized hole.

The diaphragm comprises a diaphragm ring and a diaphragm which are combined into a whole, the diaphragm ring is arranged on the shell, and the insulating ring and the back plate are arranged on the diaphragm.

The diaphragm is provided with an annular gasket, and the insulating ring and the back plate are arranged on the gasket.

The damping assembly comprises a damping plate arranged on the first copper ring, a damping plate sound hole is formed in the middle of the damping plate, and the damping assembly further comprises damping covered on the damping plate sound hole.

Wherein, the outer side of the shell sealing end is provided with a dust screen.

The noise reduction circuit comprises a printing part and a component part; the printed part comprises a positive electrode output pad and a negative electrode output pad which are arranged on the front surface of the circuit board, a first positive electrode area and a first negative electrode area which are arranged on the back surface of the circuit board and are respectively electrically connected with the positive electrode output pad and the negative electrode output pad, and a first conductive area which is electrically connected with the back plate; the first conductive region is electrically connected with a first conductive bonding pad, a plurality of positive bonding pads are arranged on the first positive region, and a plurality of negative bonding pads are arranged on the negative region.

A second positive electrode area is arranged on the lower side of the first positive electrode area, and a plurality of positive electrode bonding pads are arranged on the second positive electrode area; a strip-shaped second conductive area which is vertically arranged is arranged on the lower side of the first conductive bonding pad, and a second conductive bonding pad and a third conductive bonding pad are respectively arranged at the upper end and the lower end of the second conductive area; the first conductive region surrounds the peripheries of the negative electrode region and the second conductive region, and the first conductive region, the second conductive region and the negative electrode region are isolated by a first insulating region; the negative electrode area surrounds the peripheries of the first positive electrode area and the second positive electrode area, and the first positive electrode area, the second positive electrode area and the negative electrode area are isolated by a second insulating area.

The positive output pad is electrically connected with the first positive region through a positive metallization hole, and the negative output pad is electrically connected with the negative region through a negative metallization hole; the positive electrode bonding pad positioned on the first positive electrode area comprises a first positive electrode bonding pad positioned on the left lower side of the positive electrode metallization hole and a second positive electrode bonding pad positioned on the lower side of the first positive electrode bonding pad; the positive electrode bonding pad positioned on the second positive electrode area comprises a fourth positive electrode bonding pad positioned on the lower side of the second positive electrode bonding pad, a third positive electrode bonding pad positioned on the left side of the fourth positive electrode bonding pad and a fifth positive electrode bonding pad positioned on the right lower side of the fourth positive electrode bonding pad; the negative electrode pad includes a first negative electrode pad located on a left side of the first positive electrode pad, a second negative electrode pad located on a left side of the third positive electrode pad, and a third negative electrode pad located on a lower side of the fifth positive electrode pad.

The component part comprises a field effect tube, a grid electrode of the field effect tube is electrically connected with a first resistor, the first resistor is electrically connected with the back plate, a drain electrode of the field effect tube is electrically connected with one end of a first capacitor and a second resistor at the same time, the second resistor is electrically connected with one end of a second capacitor and the positive electrode output pad at the same time, and a source electrode of the field effect tube is electrically connected with the shell, the other end of the first capacitor, the other end of the second capacitor and the negative electrode output pad.

The grid electrode of the field effect transistor is welded on the third conductive bonding pad, the drain electrode of the field effect transistor is welded on the fifth positive bonding pad, and the source electrode of the field effect transistor is welded on the third negative bonding pad; the both ends of first resistance weld respectively on first electrically conductive pad and the electrically conductive pad of second, the both ends of second resistance weld respectively the fourth anodal pad with on the anodal pad of second, the both ends of first electric capacity weld respectively on third anodal pad and the second negative pole pad, the both ends of second electric capacity weld respectively on first anodal pad and first negative pole pad.

After the technical scheme is adopted, the utility model has the beneficial effects that:

because the unidirectional noise reduction microphone comprises the shell with one open end, the open end of the shell is provided with the circuit board, the closed end of the shell is provided with the shell sound hole, and the circuit board is provided with the circuit board sound hole; a vibrating diaphragm is arranged on the inner side of the sealed end of the shell, a back plate and an insulating ring are arranged on the vibrating diaphragm, a first copper ring is arranged on the back plate, a damping component is arranged on the first copper ring, a second copper ring is arranged on the damping component, and the circuit board is arranged on the second copper ring and the insulating ring; the circuit board is provided with a noise reduction circuit; the circuit board sound hole is the metallization hole. The noise reduction microphone directly faces the sound hole of the shell, the sound directly enters the sound hole of the shell and acts on the vibrating diaphragm, and the noise entering the sound hole of the circuit board in other directions is weakened or eliminated by the damping action of the damping component, so that the effect of reducing part of noise can be achieved; meanwhile, the noise reduction circuit can further play a role in reducing noise and resisting interference, so that the noise reduction microphone disclosed by the utility model achieves a good noise reduction effect through the dual combination of the noise reduction structure and the noise reduction circuit, the anti-interference capability is strong, the use requirements of various noisy environments can be met, the output sound signal is noiseless, and the definition is good.

In conclusion, the unidirectional noise reduction microphone solves the technical problem that an electret microphone in the prior art is poor in noise reduction effect, is good in noise reduction effect and strong in anti-jamming capability, and outputs a sound signal without noise and with good definition.

Drawings

FIG. 1 is an exploded view of a single directional noise reduction microphone according to the present invention;

FIG. 2 is a schematic diagram of the internal structure of a single directional noise reduction microphone according to the present invention;

fig. 3 is a schematic diagram of a back side structure of the circuit board in fig. 1;

fig. 4 is a schematic front structure view of the circuit board in fig. 1;

FIG. 5 is a circuit schematic of a single directional noise reduction microphone of the present invention;

in the figure: 10. dust screen, 20, case, 22, case acoustic port, 30, diaphragm, 32, diaphragm ring, 34, diaphragm, 40, spacer, 50, backplate, 52, backplate acoustic port, 60, insulator ring, 70, first copper ring, 72, second copper ring, 80, damper plate, 800, damper plate acoustic port, 82, damper, 90, circuit board, 92, circuit board acoustic port, 100, positive output pad, 102, negative output pad, 110, first insulating region, 112, second insulating region, 114, third insulating region, 116, fourth insulating region, 120, first conductive region, 122, second conductive region, 124, first conductive pad, 126, second conductive pad, 128, third conductive pad, 130, first positive region, 132, second positive region, 134, positive metalized hole, 136, first positive electrode pad, 138, second positive electrode pad, 140, third positive electrode pad, 142, fourth positive electrode, 144. a fifth positive electrode pad 150, a negative electrode region 152, a negative electrode metallization hole 154, a first negative electrode pad 156, a second negative electrode pad 158, a third negative electrode pad 160, a ground region 162, a ground conduction region, C1, a first capacitor, C2, a second capacitor, a FET, a field effect transistor, R1, a first resistor, R2, and a second resistor.

Detailed Description

The utility model is further illustrated below with reference to the figures and examples.

All the orientations referred to in the present specification are based on the orientations shown in the drawings, and only represent relative positional relationships, not absolute positional relationships.

As shown in fig. 1 and fig. 2, a single-directional noise reduction microphone includes a housing 20 with an open end, a circuit board 90 is disposed at the open end of the housing 20, an edge portion of the open end of the housing 20 is bent inward and pressed on an outer side of the circuit board 90 to constrain the circuit board 90 in the housing 20, and the housing 20 and the circuit board 90 together form a microphone package casing. The sealed end of the casing 20 is provided with a casing sound hole 22, and the circuit board 90 is provided with a circuit board sound hole 92. And a vibrating diaphragm 30, a gasket 40, a back plate 50, an insulating ring 60, a first copper ring 70, a damping component and a second copper ring 72 are arranged in a packaging body between the shell sound hole 22 and the circuit board sound hole 92.

As shown in fig. 2, a diaphragm 30 is disposed on the inner side of the sealed end of the housing 20, a back plate 50 and an insulating ring 60 are disposed on the diaphragm 30, the insulating ring 60 surrounds the periphery of the back plate 50, the height of the insulating ring 60 is greater than that of the back plate 50, and a plurality of back plate sound holes 52 are disposed on the back plate 50. In this embodiment, the diaphragm 30 is further provided with an annular spacer 40, and the insulating ring 60 and the back plate 50 are disposed on the spacer 40. The back plate 50 is provided with a first copper ring 70, and the first copper ring 70 is arranged at the edge part of the back plate 50 and is attached to the inner wall of the insulating ring 60. The first copper ring 70 is provided with a damping component, the damping component is provided with a second copper ring 72, and the insulating ring 60 surrounds the peripheries of the first copper ring 70, the damping component and the second copper ring 72, so that the back plate 50, the first copper ring 70, the damping component and the second copper ring 72 are isolated from the shell 20. In this embodiment, the upper end of the second copper ring 72 is preferably flush with the upper end of the insulating ring 60, and the circuit board 90 is disposed on the second copper ring 72 and the insulating ring 60.

As shown in fig. 2, the diaphragm 30 includes a diaphragm ring 32 and a diaphragm 34 that are integrated. The diaphragm ring 32 is disposed on the housing 20 and the spacer 40 is disposed on the diaphragm 34, i.e., the insulating ring 60 and the back plate 50 are disposed on the diaphragm 34.

As shown in fig. 1 and 2, the damping assembly includes a damping plate 80 disposed on the first copper ring 70, a damping plate sound hole 800 disposed in a middle portion of the damping plate 80, and a damper 82 covering the damping plate sound hole 800. The diameter of the damper 82 is smaller than that of the damping plate 80, the damper 82 is attached and fixed to the middle of the damping plate 80, and the diameter of the damper 82 is smaller than the inner diameter of the second copper ring 72, so that the damper plays a role in damping sound entering from the circuit board sound hole 92.

As shown in fig. 1 and 2, a plurality of circuit board sound holes 92 are provided, and in the present embodiment, it is preferable that the circuit board sound holes 92 are located on the same circumference and are arranged at equal intervals. Further preferably, each of the board sound holes 92 is a metalized hole.

As shown in fig. 1 and fig. 2, a dust screen 10 is disposed outside the sealed end of the housing 20, and the dust screen 10 can effectively prevent external dust and impurities from entering the enclosure from the housing sound hole 22.

As shown in fig. 3 and 4, the circuit board 90 is provided with a noise reduction circuit, and the noise reduction circuit includes a printed portion and a component portion. The circuit board 90 includes a front surface and a back surface, and in this embodiment, the surface of the circuit board 90 exposed outside the housing 20 is defined as the front surface, and the surface sealed inside the housing 20 is defined as the back surface.

As shown collectively in fig. 3 and 4, the printed portion includes positive output pads 100 and negative output pads 102 disposed on the front surface of the wiring board 90 and a ground region 160. The back side of the wiring board 90 is provided with a first positive region 130, a second positive region 132, a negative region 150, a first conductive region 120 and a second conductive region 122. The circuit board 90 is further provided with a positive electrode metallization hole 134 and a negative electrode metallization hole 152 penetrating through the front surface and the back surface, the first positive electrode region 130 is electrically connected with the positive electrode output pad 100 through the positive electrode metallization hole 134, and the negative electrode region 150 is electrically connected with the negative electrode output pad 102 through the negative electrode metallization hole 152. In this embodiment, the positive metallization hole 134 is preferably located within the positive output pad 100, and the negative metallization hole 152 is preferably located within the negative output pad 102.

As shown in fig. 3, the first conductive area 120 is a ring with a notch facing upward and is disposed at the edge of the back side of the circuit board 90, and the first conductive area 120 is electrically connected to the back plate 50 through the second copper ring 72, the damping plate 80 and the first copper ring 70. The first conductive region 120 surrounds the outer circumference of the negative electrode region 150 and the second conductive region 122, and the second conductive region 122 is positioned at the inner side of the first conductive region 120 and is positioned adjacent to the first conductive region 120. The first conductive region 120, the second conductive region 122, and the negative region 150 are separated by the first insulating region 110. The negative electrode region 150 surrounds the outer circumferences of the first and second positive electrode regions 130 and 132, and the second positive electrode region 132 is located on the lower side of the first positive electrode region 130. The first positive electrode region 130, the second positive electrode region 132 and the negative electrode region 150 are separated from one another by a second insulating region 112.

As shown in fig. 3, the first conductive area 120 is electrically connected to a first conductive pad 124, and the first conductive pad 124 is located at the left side of the right inner edge of the first conductive area 120 and electrically connected to the first conductive area 120 through a conductive portion extending leftward from the right inner edge of the first conductive area 120. The second conductive area 122 is located on the lower side of the first conductive pad 124, the second conductive area 122 is strip-shaped and is vertically disposed, a second conductive pad 126 and a third conductive pad 128 are respectively disposed at the upper end and the lower end of the second conductive area 122, wherein the second conductive pad 126 is located above the third conductive pad 128. The second conductive pad 126 and the third conductive pad 128 are electrically connected by a conductive portion.

As shown in fig. 3, the first positive electrode region 130 is provided with a plurality of positive electrode pads, and in the present embodiment, two positive electrode pads, which are defined as a first positive electrode pad 136 and a second positive electrode pad 138, are preferably provided on the first positive electrode region 130. The first positive electrode pad 136 is located at the lower left side of the positive electrode metallization hole 134, the second positive electrode pad 138 is located at the lower side of the first positive electrode pad 136, and the positive electrode metallization hole 134, the first positive electrode pad 136 and the second positive electrode pad 138 are electrically connected through a conductive portion. A plurality of positive electrode pads are also provided on the second positive electrode region 132, and in the present embodiment, three positive electrode pads, which are defined as a third positive electrode pad 140, a fourth positive electrode pad 142, and a fifth positive electrode pad 144, are preferably provided on the second positive electrode region 132. The fourth positive pad 142 is located on the lower side of the second positive pad 138 and on the left side of the second conductive pad 126. The third positive electrode pad 140 is positioned at the left side of the fourth positive electrode pad 142. The fifth positive pad 144 is positioned at the lower right side of the fourth positive pad 142, and at the lower left side of the second conductive pad 126, and at the upper left side of the third conductive pad 128. The third positive electrode pad 140, the fourth positive electrode pad 142, and the fifth positive electrode pad 144 are electrically connected to each other through a conductive portion.

As shown in fig. 3, a plurality of negative electrode pads are disposed on the negative electrode region 150, and in the present embodiment, three negative electrode pads are preferably disposed on the negative electrode region 150, which are respectively defined as a first negative electrode pad 154, a second negative electrode pad 156, and a third negative electrode pad 158. The first negative electrode pad 154 is positioned at the left side of the first positive electrode pad 136 and at the upper side of the third positive electrode pad 140. The second negative electrode pad 156 is located to the left of the third positive electrode pad 140 and below the negative electrode metallization hole 152. The third negative electrode pad 158 is positioned on the lower side of the fifth positive electrode pad 144 and on the lower left side of the third conductive pad 128. The other parts of the negative electrode region 150 are laid with conductive metal sheets coated with solder resist.

As shown in fig. 3 and 4, the front surface of the circuit board 90 is provided with a grounding area 160, the edge of the grounding area 160 is provided with a ring of grounding conductive area 162, the grounding conductive area 162 is used for electrically connecting with the housing 20, the grounding area 160 is laid with a conductive metal sheet, and the conductive metal sheet except the grounding conductive area 162 is coated with solder resist. The positive output pad 100 and the negative output pad 102 are both located in the middle of the ground region 160. Positive output pad 100 is isolated from ground region 160 by third insulating region 114. The negative output pad 102 is isolated from the grounding area 160 through the fourth insulating area 116, four conductive parts are arranged on the fourth insulating area 116, and the four conductive parts are used for electrically connecting the negative output pad 102 with the grounding area 160, so that the negative area 150 is electrically connected with the grounding area 160, meanwhile, each circuit board sound hole 92 is a metalized hole, the effect of electrically connecting the negative area 150 with the grounding area 160 is also achieved, the grounding area of the circuit board 90 is increased, and the anti-interference performance of the microphone can be improved.

As shown in fig. 3 and 4 in common, in the present embodiment, each conductive portion is preferably made of a conductive wire or a conductive metal strip, and each of the conductive wire and the conductive metal strip is coated with a solder resist.

As shown in fig. 3, 4 and 5, the component part includes a FET, a gate G of the FET is electrically connected to the first resistor R1, the first resistor R1 is electrically connected to the back plate 50, a drain D of the FET is electrically connected to the second resistor R2 and one end of the first capacitor C1, the second resistor R2 is electrically connected to one end of the second capacitor C2 and the positive output pad 100, and a source S of the FET is electrically connected to the housing 20, the other end of the first capacitor C1, the other end of the second capacitor C2 and the negative output pad 102. The first resistor R1 can play a role in noise reduction, and the second resistor R2, the first capacitor C1 and the second capacitor C2 form a resistance-capacitance filter circuit, so that the functions of filtering and resisting disturbance can be played.

As shown in fig. 3, the gate G of the FET is soldered to the third conductive pad 128, the drain D is soldered to the fifth positive pad 144, and the source S is soldered to the third negative pad 158. Two ends of the first resistor R1 are respectively soldered to the first conductive pad 124 and the second conductive pad 126, two ends of the second resistor R2 are respectively soldered to the fourth positive pad 142 and the second positive pad 138, two ends of the first capacitor C1 are respectively soldered to the third positive pad 140 and the second negative pad 156, and two ends of the second capacitor C2 are respectively soldered to the first positive pad 136 and the first negative pad 154.

The unidirectional noise reduction microphone has the advantages of good noise effect, strong anti-interference capability, no noise of output sound signals and good definition.

The present invention is not limited to the above-described embodiments, and various modifications made by those skilled in the art without inventive skill from the above-described conception fall within the scope of the present invention.

Claims (10)

1. The unidirectional noise reduction microphone comprises a shell (20) with an open end, wherein a circuit board (90) is arranged at the open end of the shell (20), and is characterized in that a shell sound hole (22) is arranged at the sealing end of the shell (20), and a circuit board sound hole (92) is arranged on the circuit board (90); a vibrating diaphragm (30) is arranged on the inner side of the sealing end of the shell (20), a back plate (50) and an insulating ring (60) are arranged on the vibrating diaphragm (30), a first copper ring (70) is arranged on the back plate (50), a damping assembly is arranged on the first copper ring (70), a second copper ring (72) is arranged on the damping assembly, and the circuit board (90) is arranged on the second copper ring (72) and the insulating ring (60); a noise reduction circuit is arranged on the circuit board (90); the circuit board sound holes (92) are metalized holes.

2. The microphone of claim 1, wherein the diaphragm (30) comprises a membrane ring (32) and a diaphragm (34) integrated into a single body, the membrane ring (32) is disposed on the housing (20), and the insulating ring (60) and the backplate (50) are disposed on the diaphragm (34).

3. The uni-directional noise reduction microphone according to claim 2 wherein the diaphragm (34) is provided with an annular spacer (40), the insulating ring (60) and the backplate (50) being provided on the spacer (40).

4. The single directional noise reduction microphone according to claim 2, wherein the damping assembly comprises a damping plate (80) disposed on the first copper ring (70), a damping plate sound hole (800) is disposed in a middle portion of the damping plate (80), and the damping assembly further comprises a damper (82) covering the damping plate sound hole (800).

5. The microphone of claim 1, wherein a dust screen (10) is provided outside the closed end of the housing (20).

6. The unidirectional noise reduction microphone of claim 1, wherein the noise reduction circuit comprises a printed portion and a component portion; the printed part comprises a positive output pad (100) and a negative output pad (102) arranged on the front surface of the circuit board (90), and further comprises a first positive region (130) and a negative region (150) arranged on the back surface of the circuit board (90) and respectively electrically connected with the positive output pad (100) and the negative output pad (102), and a first conductive region (120) electrically connected with the back plate (50); the first conductive area (120) is electrically connected with a first conductive pad (124), the first positive electrode area (130) is provided with a plurality of positive electrode pads, and the negative electrode area (150) is provided with a plurality of negative electrode pads.

7. The microphone of claim 6, wherein the first positive electrode region (130) has a second positive electrode region (132) disposed on an underside thereof, the second positive electrode region (132) having a plurality of positive electrode pads disposed thereon; a strip-shaped second conductive area (122) which is vertically arranged is arranged on the lower side of the first conductive pad (124), and a second conductive pad (126) and a third conductive pad (128) are respectively arranged at the upper end and the lower end of the second conductive area (122); the first conductive region (120) surrounds the negative region (150) and the second conductive region (122), and the first conductive region (120), the second conductive region (122) and the negative region (150) are isolated by a first insulating region (110); the negative electrode region (150) surrounds the peripheries of the first positive electrode region (130) and the second positive electrode region (132), and the first positive electrode region (130), the second positive electrode region (132) and the negative electrode region (150) are isolated by a second insulating region (112).

8. The single direction noise reducing microphone of claim 7, wherein the positive output pad (100) is electrically connected to the first positive region (130) through a positive metallization hole (134), and the negative output pad (102) is electrically connected to the negative region (150) through a negative metallization hole (152); the positive electrode pads on the first positive electrode region (130) include a first positive electrode pad (136) on a lower left side of the positive electrode metallization hole (134) and a second positive electrode pad (138) on a lower side of the first positive electrode pad (136); the positive electrode pads on the second positive electrode region (132) include a fourth positive electrode pad (142) on a lower side of the second positive electrode pad (138), a third positive electrode pad (140) on a left side of the fourth positive electrode pad (142), and a fifth positive electrode pad (144) on a right lower side of the fourth positive electrode pad (142); the negative electrode pads include a first negative electrode pad (154) located to the left of the first positive electrode pad (136), a second negative electrode pad (156) located to the left of the third positive electrode pad (140), and a third negative electrode pad (158) located to the lower side of the fifth positive electrode pad (144).

9. The microphone of claim 8, wherein the component part comprises a Field Effect Transistor (FET), a gate of the FET is electrically connected to the first resistor (R1), the first resistor (R1) is electrically connected to the back plate (50), a drain of the FET is electrically connected to one end of the first capacitor (C1) and the second resistor (R2), the second resistor (R2) is electrically connected to one end of the second capacitor (C2) and the positive output pad (100), and a source of the FET is electrically connected to the housing (20), the other end of the first capacitor (C1), the other end of the second capacitor (C2) and the negative output pad (102).

10. The microphone of claim 9, wherein the gate of the Field Effect Transistor (FET) is soldered to the third conductive pad (128), the drain of the Field Effect Transistor (FET) is soldered to the fifth positive pad (144), and the source of the Field Effect Transistor (FET) is soldered to the third negative pad (158); the both ends of first resistance (R1) weld respectively on first electrically conductive pad (124) and second electrically conductive pad (126), the both ends of second resistance (R2) weld respectively fourth positive pad (142) with on second positive pad (138), the both ends of first electric capacity (C1) weld respectively on third positive pad (140) and second negative pole pad (156), the both ends of second electric capacity (C2) weld respectively on first positive pad (136) and first negative pole pad (154).

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