Flexible circuit board

Abstract

The flexible circuit board comprises a component layer, a surface insulating coating, a surface circuit layer, an FPC substrate layer, a bottom surface circuit layer and a bottom surface insulating coating which are sequentially distributed from top to bottom, the lower surface of the surface insulating coating is in face-to-face fit with the upper surface of the FPC substrate layer, the lower surface of the FPC substrate layer is in face-to-face fit with the upper surface of the bottom surface insulating coating, and the surface circuit layer is clamped between the lower surface of the surface insulating coating and the upper surface of the FPC substrate layer. The bottom surface circuit layer is clamped between the lower surface of the FPC substrate layer and the upper surface of the bottom surface insulating coating, and the surface circuit layer and the bottom surface circuit layer are respectively provided with circuits which operate independently and have different functions. Therefore, the design can provide the flexible circuit board which has different functions, operates independently and does not interfere with each other and is not less than two layers of circuits.

Description

Technical Field

[0001] The utility model relates to a circuit board, belongs to the field of electronic science, and particularly relates to a flexible circuit board. Background Art

[0002] Flexible circuit boards are widely used in the field of electronic product processing. Due to their high assembly density, small size, light weight, and bendability, they can meet the requirements of high density, miniaturization, and high reliability of electronic products. They are mostly used in electronic products such as smart phones, tablet computers, and wearable devices.

[0003] The Chinese patent with application number CN202311862858.4 and application date December 29, 2023 discloses a high-frequency and high-speed FPC multilayer board. The technical solution is as follows: the lower covering layer adopts polyimide film, which has good insulation, heat resistance and high mechanical strength to provide protection for the circuit board. The current-carrying layer, as the main current-carrying part in the circuit board, is composed of thick copper foil, ensuring the requirements of high conductivity and mechanical strength. The signal layer is the key part for processing signals. It is made of copper-clad laminate and various circuits are etched to ensure the accuracy and stability of signal transmission. The insulating layer is located above the signal layer, and its main function is to provide electrical insulation to prevent mutual interference and short circuit problems between different signal layers. The copper foil layer is located above the insulating layer and is composed of thin copper foil with good conductivity and mechanical processing performance. The anti-soldering layer is located above the copper foil layer as a protective layer, which effectively prevents damage to the circuit board during welding. As the top layer of the circuit board, the upper covering layer also plays a role in protecting the internal structure. Although this design can provide a high-frequency and high-speed FPC multilayer board with excellent electrical performance, mechanical performance and environmental adaptability, it still has the following defects:

[0004] This design cannot allow the flexible circuit board to have more than or equal to two layers of circuits with different functions and independent operation.

[0005] The information disclosed in this background technology section is only intended to increase the understanding of the overall background of this patent application, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to ordinary technicians in this field. Summary of the invention

[0006] The purpose of the utility model is to overcome the defects and problems existing in the prior art that a flexible circuit board cannot simultaneously have more than or equal to two layers of circuits with different functions and independent operation, and to provide a flexible circuit board with no less than two layers of circuits that can simultaneously have different functions, operate independently, and do not interfere with each other.

[0007] To achieve the above purpose, the technical solution of the utility model is: a flexible circuit board, comprising a component layer, a surface insulating coating, a surface circuit layer, an FPC matrix layer, a bottom circuit layer, and a bottom insulating coating, which are sequentially distributed from top to bottom; the lower surface of the surface insulating coating is face-to-face bonded to the upper surface of the FPC matrix layer, the lower surface of the FPC matrix layer is face-to-face bonded to the upper surface of the bottom insulating coating, the surface circuit layer is sandwiched between the lower surface of the surface insulating coating and the upper surface of the FPC matrix layer, and the bottom circuit layer is sandwiched between the lower surface of the FPC matrix layer and the upper surface of the bottom insulating coating;

[0008] The upper half of the component layer is the control circuit area, and the lower half is the power circuit area; the surface insulating coating includes a surface main board and a plurality of surface support boards, the upper half of the surface main board is the surface control area, and the lower half is the surface power area, the surface control area is distributed with a plurality of first holes, and the surface power area is distributed with a plurality of second holes; the surface circuit layer is divided into a surface main circuit area and a plurality of surface branch circuit areas, the upper half of the surface main circuit area is the surface control circuit, and the lower half is the surface power circuit, the surface control circuit is circuit-connected with the surface power circuit, the surface branch circuit area is distributed with resistance wires, and the resistance wires are circuit-connected with the surface main circuit area; The FPC substrate layer includes a substrate main board and a plurality of substrate support boards, the upper half of the substrate main board is a substrate control area, the lower half is a substrate power area, the substrate control area is provided with a plurality of first vias, and the substrate power area is provided with a plurality of second vias; the bottom circuit layer is divided into a bottom main circuit area and a plurality of copper sheets, the upper half of the bottom main circuit area is a bottom control circuit, the lower half is a bottom power circuit, the bottom control circuit is connected to the bottom power circuit, and the copper sheet is connected to the bottom main circuit area through a connecting circuit; the bottom insulating coating includes a bottom main board and a plurality of bottom support boards, and the bottom support boards are provided with corresponding empty windows;

[0009] The control circuit area sequentially passes through the first hole to contact the surface control circuit, and the power circuit area sequentially passes through the second hole to contact the surface power circuit; the control circuit area sequentially passes through the first hole, the surface control circuit, and the first via to contact the bottom control circuit, and the power circuit area sequentially passes through the second hole, the surface power circuit, and the second via to contact the bottom power circuit; the control circuit area is circuit-connected with the surface control circuit, and the power circuit area is circuit-connected with the surface power circuit; the control circuit area is circuit-connected with the bottom control circuit, and the power circuit area is circuit-connected with the bottom power circuit; the power circuit area is circuit-connected with the power module; the surface support plate, the matrix layer support plate and the bottom support plate have the same area; the area of ​​the surface support circuit area is less than or equal to the area of ​​the surface support plate; the empty window corresponds to the copper sheet up and down, and the area of ​​the empty window is less than or equal to the area of ​​the copper sheet.

[0010] A first connection resistance wire is arranged on the left side of the surface control circuit and the surface power supply circuit, and a second connection resistance wire is arranged on the right side of the surface control circuit and the surface power supply circuit;

[0011] The number of the resistance wires is four, namely a first loop branch, a second loop branch, a third loop branch, and a fourth loop branch;

[0012] The surface control circuit is circuit-connected to one end of the first loop branch, the other end of the first loop branch is circuit-connected to the upper end of the first connection resistance wire, the lower end of the first connection resistance wire is circuit-connected to one end of the second loop branch, the other end of the second loop branch is circuit-connected to the surface control circuit, and at the same time, the surface control circuit is circuit-connected to one end of the third loop branch, the other end of the third loop branch is circuit-connected to the lower end of the second connection resistance wire, the upper end of the second connection resistance wire is circuit-connected to one end of the fourth loop branch, and the other end of the fourth loop branch is circuit-connected to the surface control circuit;

[0013] The first connection resistance wire and the second connection resistance wire are both of a meandering structure.

[0014] The number of the copper sheets and the connecting circuits are both four, and they correspond one to one; a single copper sheet is connected to one end of its corresponding connecting circuit, and the other end of the connecting circuit is connected to the bottom power supply circuit.

[0015] The copper sheet includes a first rectangular area, a second rectangular area and a grid area. The first rectangular area and the second rectangular area have the same structure, and the grid area is evenly distributed with penetrating grid holes.

[0016] The exposed portion of the copper sheet relative to the corresponding empty window is connected to the conductive TPU sheet by means of a conductive double-sided adhesive.

[0017] A program input area is arranged in the middle area between the surface control circuit and the surface power supply circuit, and the program input area has four program burning ports.

[0018] The power module includes an external power circuit board, a charging port and a battery, and the external power circuit board is circuit-connected to the charging port and the battery;

[0019] The battery is connected to the surface power circuit and the bottom power circuit respectively through an external power circuit board.

[0020] A control area reinforcement sheet and a power area reinforcement sheet are attached to the lower surface of the bottom mainboard. The control area reinforcement sheet corresponds to the control circuit area up and down, and the power area reinforcement sheet corresponds to the power circuit area up and down.

[0021] Solder points are distributed on the upper edge of the control circuit area. The solder points pass through the first holes in sequence to contact the surface control circuit. The solder points pass through the first holes, the surface control circuit, and the first via holes in sequence to contact the bottom control circuit. The solder points are circuit-connected to the surface control circuit. The solder points are circuit-connected to the bottom control circuit.

[0022] The material of the surface insulating coating is polyimide, the material of the FPC matrix layer is polyimide, and the material of the bottom insulating coating is polyimide.

[0023] Compared with the prior art, the beneficial effects of the utility model are:

[0024] 1. The utility model discloses a flexible circuit board, which includes a component layer, a surface insulating coating, a surface circuit layer, an FPC matrix layer, a bottom circuit layer, and a bottom insulating coating, which are sequentially distributed from top to bottom; the lower surface of the surface insulating coating is face-to-face bonded to the upper surface of the FPC matrix layer, the lower surface of the FPC matrix layer is face-to-face bonded to the upper surface of the bottom insulating coating, the surface circuit layer is sandwiched between the lower surface of the surface insulating coating and the upper surface of the FPC matrix layer, and the bottom circuit layer is sandwiched between the lower surface of the FPC matrix layer and the upper surface of the bottom insulating coating; the upper half of the component layer is a control circuit area, and the lower half is a power circuit area; the surface insulating coating includes a surface motherboard and several surface The surface support board, the upper half of the surface main board is the surface control area, the lower half is the surface power supply area, the surface control area is distributed with a plurality of first holes, and the surface power supply area is distributed with a plurality of second holes; the surface circuit layer is divided into a surface main circuit area and a plurality of surface branch circuit areas, the upper half of the surface main circuit area is the surface control circuit, the lower half is the surface power supply circuit, the surface control circuit is circuit-connected with the surface power supply circuit, the surface branch circuit area is distributed with resistance wires, and the resistance wires are circuit-connected with the surface main circuit area; the FPC matrix layer includes a matrix layer main board and a plurality of matrix layer support boards, the upper half of the matrix layer main board is the matrix layer control area, the lower half is the matrix layer power supply area, the matrix layer The control area is provided with a plurality of first via holes, and the power supply area of ​​the substrate layer is provided with a plurality of second via holes; the bottom circuit layer is divided into a bottom main circuit area and a plurality of copper sheets, the upper half of the bottom main circuit area is a bottom control circuit, and the lower half is a bottom power supply circuit, the bottom control circuit of the bottom circuit layer is circuit-connected with the bottom power supply circuit, and the copper sheet is circuit-connected with the bottom main circuit area through a connecting circuit; the bottom insulating coating includes a bottom main board and a plurality of bottom support plates, and the bottom support plates are provided with corresponding empty windows; the control circuit area sequentially passes through the first hole to contact with the surface control circuit, and the power supply circuit area sequentially passes through the second hole to contact with the surface power supply circuit; the control circuit area sequentially passes through the first hole The surface control circuit and the first via are in contact with the bottom control circuit, and the power circuit area passes through the second hole, the surface power circuit and the second via in sequence and contacts the bottom power circuit; the control circuit area is circuit-connected with the surface control circuit, and the power circuit area is circuit-connected with the surface power circuit; the control circuit area is circuit-connected with the bottom control circuit, and the power circuit area is circuit-connected with the bottom power circuit; the power circuit area is circuit-connected with the power module; the surface support plate, the matrix layer support plate and the bottom support plate have the same area; the area of ​​the surface support circuit area is less than or equal to the area of ​​the surface support plate; the empty window corresponds to the copper sheet up and down, and the area of ​​the empty window is less than or equal to the area of ​​the copper sheet.When used, in the surface circuit layer, the power module provides current to the surface control circuit through the surface power circuit, and the current flows into the resistance wire of the surface branch circuit area through the control of the surface control circuit, so that the resistance wire generates heat; in the bottom circuit layer, the power module provides current to the bottom control circuit through the bottom power circuit, and the circuit flows through the copper sheet to generate heat, which is transmitted by the copper sheet; the existence of the FPC matrix layer allows the circuits between the surface circuit layer and the bottom circuit layer to operate independently without interfering with each other. Therefore, the flexible circuit board of the utility model can arrange two layers of circuits with different functions, which operate independently and do not interfere with each other.

[0025] 2. In a flexible circuit board of the utility model, a first connecting resistor is arranged on the left side of a surface control circuit and a surface power supply circuit, and a second connecting resistor is arranged on the right side of the surface control circuit and the surface power supply circuit; the number of the resistors is four, namely a first loop branch, a second loop branch, a third loop branch, and a fourth loop branch; the surface control circuit is circuit-connected to one end of the first loop branch, the other end of the first loop branch is circuit-connected to the upper end of the first connecting resistor, the lower end of the first connecting resistor is circuit-connected to one end of the second loop branch, and the other end of the second loop branch is circuit-connected to the surface control circuit; at the same time, the surface control circuit is circuit-connected to one end of the third loop branch, the other end of the third loop branch is circuit-connected to the lower end of the second connecting resistor, the upper end of the second connecting resistor is circuit-connected to one end of the fourth loop branch, and the other end of the fourth loop branch is circuit-connected to the surface control circuit; the first connecting resistor and the second connecting resistor are both loop structures. When used, the current passes through the surface control circuit and flows to the four loop branches. When the current passes through the resistance wire of each loop branch, the current generates heat due to work. Therefore, each loop branch of the surface circuit layer of the utility model can generate heat and provide heat.

[0026] 3. In a flexible circuit board of the utility model, the number of the copper sheets and the connecting circuits are both four, and they correspond one to one; a single copper sheet is connected to one end of its corresponding connecting circuit, and the other end of the connecting circuit is connected to the bottom power supply circuit. The copper sheet includes a first rectangular area, a second rectangular area and a grid area. The first rectangular area and the second rectangular area have the same structure, and the grid area is evenly distributed with through grid holes. The exposed part of the copper sheet relative to its corresponding empty window is connected to the conductive TPU sheet by conductive double-sided adhesive;

[0027] When used, the current flows to the four copper sheets through the bottom control circuit, causing the copper sheets to heat up; on this basis, the bottom control circuit can also control the intermittent conduction of the current in the entire circuit (the bottom control circuit can be edited according to the existing technology) so that the intermittent current flows through the copper sheets, so that the receptors attached to the copper sheets continue to feel the regular intermittent current stimulation, thereby producing a pulse effect;

[0028] Whether it is the heating of the copper sheet or the pulse stimulation, the stimulation to the receptor is too strong, so a conductive TPU sheet is required. The conductive TPU sheet can not only provide a certain heat insulation effect on the heat generated by the copper sheet, but also reduce the stimulation of the intermittent current on the receptor. Therefore, the utility model can not only generate heat energy independently, but also produce a pulse effect and improve the comfort of the receptor.

[0029] 4. In a flexible circuit board of the utility model, the power module includes an external power circuit board, a charging port and a battery. The external power circuit board is circuit-connected with the charging port and the battery; the battery is circuit-connected with the surface power circuit and the bottom power circuit respectively through the external power circuit board. When in use, the charging port is connected to an external power source to charge the battery, and the battery provides power for the flexible circuit board; the charging port can also be connected to an external power source to directly provide power for the flexible circuit board to work; in addition, the battery can be integrated on the flexible circuit board to make it smaller. Therefore, the utility model can provide two power supply modes, which is convenient for use in a variety of scenarios and is also more portable. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a structural schematic diagram of the utility model.

[0031] Figure 2 It is a structural schematic diagram of the component layer of the utility model.

[0032] Figure 3 It is a structural schematic diagram of the surface insulating coating of the utility model.

[0033] Figure 4 It is a structural schematic diagram of the surface circuit layer of the utility model.

[0034] Figure 5 It is a structural schematic diagram of the FPC matrix layer of the utility model.

[0035] Figure 6 It is a structural schematic diagram of the bottom circuit layer of the utility model.

[0036] Figure 7 It is a structural schematic diagram of the bottom insulating coating of the utility model.

[0037] Figure 8 It is a structural schematic diagram of the copper sheet of the utility model.

[0038] Fig. 9 It is a structural schematic diagram of the bottom support plate, the copper sheet and the conductive TPU sheet in the utility model.

[0039] In the figure: component layer 1, control circuit area 11, power circuit area 12, solder point 14, first solder point 141, second solder point 142, third solder point 143, fourth solder point 144, fifth solder point 145, surface insulation coating 2, surface main board 21, surface control area 211, surface power area 212, surface support board 22, first hole 231, second hole 232, surface circuit layer 3, surface main circuit area 31, surface control circuit 311, surface power circuit 312, first connecting resistor 313, second connecting resistor 314, surface branch circuit area 32, resistor 33, first round branch 331, second round branch 332, third round branch 333, fourth round branch 334, 34, program input area 34, program burning port 341, FPC matrix layer 4, matrix layer main board 41, matrix layer control area 411, matrix layer power supply area 412, matrix layer support plate 42, first via 431, second via 432, bottom circuit layer 5, bottom main circuit area 51, bottom control circuit 511, bottom power supply circuit 512, copper sheet 52, connecting circuit 521, first rectangular area 522, second rectangular area 523, grid area 524, grid hole 525, conductive TPU sheet 53, bottom insulating coating 6, bottom main board 61, bottom support plate 62, window 63, control area reinforcement sheet 71, power supply area reinforcement sheet 72, power module 8, external power supply circuit board 81, charging port 82, battery 83. DETAILED DESCRIPTION

[0040] The present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0041] See also Figure 1 — Fig. 9 A flexible circuit board comprises a component layer 1, a surface insulating coating 2, a surface circuit layer 3, an FPC matrix layer 4, a bottom circuit layer 5, and a bottom insulating coating 6 which are sequentially arranged from top to bottom; the lower surface of the surface insulating coating 2 is face-to-face bonded to the upper surface of the FPC matrix layer 4, the lower surface of the FPC matrix layer 4 is face-to-face bonded to the upper surface of the bottom insulating coating 6, the surface circuit layer 3 is sandwiched between the lower surface of the surface insulating coating 2 and the upper surface of the FPC matrix layer 4, and the bottom circuit layer 5 is sandwiched between the lower surface of the FPC matrix layer 4 and the upper surface of the bottom insulating coating 6;

[0042] The upper half of the component layer 1 is the control circuit area 11, and the lower half is the power circuit area 12; the surface insulating coating 2 includes a surface main board 21 and a plurality of surface support boards 22, the upper half of the surface main board 21 is the surface control area 211, and the lower half is the surface power area 212, the surface control area 211 is distributed with a plurality of first holes 231, and the surface power area 212 is distributed with a plurality of second holes 232; the surface circuit layer 3 is divided into a surface main circuit area 31 and a plurality of surface branch circuit areas 32, the upper half of the surface main circuit area 31 is the surface control circuit 311, and the lower half is the surface power circuit 312, the surface control circuit 311 is circuit-connected with the surface power circuit 312, the surface branch circuit area 32 is distributed with resistance wires 33, and the resistance wires 33 are circuit-connected with the surface main circuit area 31; the F The PC matrix layer 4 includes a matrix layer main board 41 and a plurality of matrix layer support boards 42, wherein the upper half of the matrix layer main board 41 is a matrix layer control area 411, and the lower half is a matrix layer power supply area 412, wherein the matrix layer control area 411 is provided with a plurality of first vias 431, and the matrix layer power supply area 412 is provided with a plurality of second vias 432; the bottom surface circuit layer 5 is divided into a bottom surface main circuit area 51 and a plurality of copper sheets 52, wherein the upper half of the bottom surface main circuit area 51 is a bottom surface control circuit 511, and the lower half is a bottom surface power supply circuit 512, wherein the bottom surface control circuit 511 is circuit-connected with the bottom surface power supply circuit 512, and the copper sheet 52 is circuit-connected with the bottom surface main circuit area 51 via a connecting circuit 521; the bottom surface insulating coating 6 includes a bottom surface main board 61 and a plurality of bottom support boards 62, wherein the bottom support boards 62 are provided with corresponding empty windows 63;

[0043] The control circuit area 11 sequentially passes through the first hole 231 to contact the surface control circuit 311, and the power circuit area 12 sequentially passes through the second hole 232 to contact the surface power circuit 312; the control circuit area 11 sequentially passes through the first hole 231, the surface control circuit 311, and the first via 431 to contact the bottom control circuit 511, and the power circuit area 12 sequentially passes through the second hole 232, the surface power circuit 312, and the second via 432 to contact the bottom power circuit 512; the control circuit area 11 is circuit-connected with the surface control circuit 311 The power circuit area 12 is circuit-connected with the surface power circuit 312; the control circuit area 11 is circuit-connected with the bottom control circuit 511, and the power circuit area 12 is circuit-connected with the bottom power circuit 512; the power circuit area 12 is circuit-connected with the power module 8; the surface support plate 22, the matrix layer support plate 42 and the bottom support plate 62 have the same area; the area of ​​the surface branch circuit area 32 is less than or equal to the area of ​​the surface support plate 22; the empty window 63 corresponds to the copper sheet 52 up and down, and the area of ​​the empty window 63 is less than or equal to the area of ​​the copper sheet 52.

[0044] A first connection resistance wire 313 is arranged on the left side of the surface control circuit 311 and the surface power supply circuit 312, and a second connection resistance wire 314 is arranged on the right side of the surface control circuit 311 and the surface power supply circuit 312;

[0045] There are four resistor wires 33, namely a first loop branch 331, a second loop branch 332, a third loop branch 333, and a fourth loop branch 334;

[0046] The surface control circuit 311 is circuit-connected to one end of the first round-shaped branch 331, the other end of the first round-shaped branch 331 is circuit-connected to the upper end of the first connection resistance wire 313, the lower end of the first connection resistance wire 313 is circuit-connected to one end of the second round-shaped branch 332, the other end of the second round-shaped branch 332 is circuit-connected to the surface control circuit 311, and at the same time, the surface control circuit 311 is circuit-connected to one end of the third round-shaped branch 333, the other end of the third round-shaped branch 333 is circuit-connected to the lower end of the second connection resistance wire 314, the upper end of the second connection resistance wire 314 is circuit-connected to one end of the fourth round-shaped branch 334, the other end of the fourth round-shaped branch 334 is circuit-connected to the surface control circuit 311;

[0047] The first connection resistance wire 313 and the second connection resistance wire 314 are both of meander-shaped structures.

[0048] There are four copper sheets 52 and four connecting circuits 521 in one-to-one correspondence. A single copper sheet 52 is connected to one end of its corresponding connecting circuit 521 , and the other end of the connecting circuit 521 is connected to the bottom power supply circuit 512 .

[0049] The copper sheet 52 includes a first rectangular area 522 , a second rectangular area 523 and a grid area 524 . The first rectangular area 522 and the second rectangular area 523 have the same structure. The grid area 524 is evenly distributed with grid holes 525 penetrating therethrough.

[0050] The exposed portion of the copper sheet 52 relative to the corresponding window 63 is adhered and connected to the conductive TPU sheet 53 via a conductive double-sided adhesive.

[0051] A program input area 34 is disposed between the surface control circuit 311 and the surface power circuit 312 . The program input area 34 includes four program burning ports 341 .

[0052] The power module 8 includes an external power circuit board 81, a charging port 82 and a battery 83, and the external power circuit board 81 is circuit-connected with the charging port 82 and the battery 83;

[0053] The battery 83 is connected to the surface power circuit 312 and the bottom power circuit 512 through the external power circuit board 81.

[0054] A control area reinforcement sheet 71 and a power area reinforcement sheet 72 are attached to the lower surface of the bottom main board 61 . The control area reinforcement sheet 71 corresponds to the control circuit area 11 up and down, and the power area reinforcement sheet 72 corresponds to the power circuit area 12 up and down.

[0055] Solder points 14 are distributed on the upper edge of the control circuit area 11. The solder points 14 pass through the first holes 231 to contact the surface control circuit 311. The solder points 14 pass through the first holes 231, the surface control circuit 311, and the first vias 431 in sequence to contact the bottom control circuit 511. The solder points 14 are circuit-connected to the surface control circuit 311, and the solder points 14 are circuit-connected to the bottom control circuit 511.

[0056] The material of the surface insulating coating 2 is polyimide, the material of the FPC matrix layer 4 is polyimide; the material of the bottom insulating coating 6 is polyimide.

[0057] The supplementary description of this utility model is as follows:

[0058] The utility model preferably packages the surface insulating coating 2, the surface circuit layer 3, the FPC matrix layer 4, the bottom circuit layer 5 and the bottom insulating coating 6 into one body.

[0059] In the present invention, the area of ​​the control area reinforcement sheet 71 is preferably greater than or equal to the area of ​​the control circuit area 11 ; the area of ​​the power area reinforcement sheet 72 is greater than or equal to the area of ​​the power circuit area 12 .

[0060] In the present invention, the control area reinforcement sheet 71 and the power area reinforcement sheet 72 are preferably made of any one or any combination of polyester, polyimide, epoxy glass fiber, phenolic, steel or aluminum.

[0061] The utility model preferably has five solder points 14 , which are a first solder point 141 , a second solder point 142 , a third solder point 143 , a fourth solder point 144 , and a fifth solder point 145 .

[0062] Embodiment 1:

[0063] See also Figure 1 — Fig. 9A flexible circuit board comprises a component layer 1, a surface insulating coating 2, a surface circuit layer 3, an FPC matrix layer 4, a bottom circuit layer 5, and a bottom insulating coating 6 which are sequentially arranged from top to bottom; the lower surface of the surface insulating coating 2 is face-to-face bonded to the upper surface of the FPC matrix layer 4, the lower surface of the FPC matrix layer 4 is face-to-face bonded to the upper surface of the bottom insulating coating 6, the surface circuit layer 3 is sandwiched between the lower surface of the surface insulating coating 2 and the upper surface of the FPC matrix layer 4, and the bottom circuit layer 5 is sandwiched between the lower surface of the FPC matrix layer 4 and the upper surface of the bottom insulating coating 6;

[0064] The upper half of the component layer 1 is the control circuit area 11, and the lower half is the power circuit area 12; the surface insulating coating 2 includes a surface main board 21 and a plurality of surface support boards 22, the upper half of the surface main board 21 is the surface control area 211, and the lower half is the surface power area 212, the surface control area 211 is distributed with a plurality of first holes 231, and the surface power area 212 is distributed with a plurality of second holes 232; the surface circuit layer 3 is divided into a surface main circuit area 31 and a plurality of surface branch circuit areas 32, the upper half of the surface main circuit area 31 is the surface control circuit 311, and the lower half is the surface power circuit 312, the surface control circuit 311 is circuit-connected with the surface power circuit 312, the surface branch circuit area 32 is distributed with resistance wires 33, and the resistance wires 33 are circuit-connected with the surface main circuit area 31; the FPC base The material layer 4 includes a matrix layer main board 41 and a plurality of matrix layer support boards 42, wherein the upper half of the matrix layer main board 41 is a matrix layer control area 411, and the lower half is a matrix layer power supply area 412, wherein the matrix layer control area 411 is provided with a plurality of first vias 431, and the matrix layer power supply area 412 is provided with a plurality of second vias 432; the bottom surface circuit layer 5 is divided into a bottom surface main circuit area 51 and a plurality of copper sheets 52, wherein the upper half of the bottom surface main circuit area 51 is a bottom surface control circuit 511, and the lower half is a bottom surface power supply circuit 512, wherein the bottom surface control circuit 511 of the bottom surface circuit layer 5 is circuit-connected with the bottom surface power supply circuit 512, and the copper sheet 52 is circuit-connected with the bottom surface main circuit area 51 via a connecting circuit 521; the bottom surface insulating coating 6 includes a bottom surface main board 61 and a plurality of bottom support boards 62, wherein the bottom surface support boards 62 are provided with corresponding empty windows 63;

[0065] The control circuit area 11 sequentially passes through the first hole 231 to contact the surface control circuit 311, and the power circuit area 12 sequentially passes through the second hole 232 to contact the surface power circuit 312; the control circuit area 11 sequentially passes through the first hole 231, the surface control circuit 311, and the first via 431 to contact the bottom control circuit 511, and the power circuit area 12 sequentially passes through the second hole 232, the surface power circuit 312, and the second via 432 to contact the bottom power circuit 512; the control circuit area 11 is circuit-connected with the surface control circuit 311 The power circuit area 12 is circuit-connected with the surface power circuit 312; the control circuit area 11 is circuit-connected with the bottom control circuit 511, and the power circuit area 12 is circuit-connected with the bottom power circuit 512; the power circuit area 12 is circuit-connected with the power module 8; the surface support plate 22, the matrix layer support plate 42 and the bottom support plate 62 have the same area; the area of ​​the surface branch circuit area 32 is less than or equal to the area of ​​the surface support plate 22; the empty window 63 corresponds to the copper sheet 52 up and down, and the area of ​​the empty window 63 is less than or equal to the area of ​​the copper sheet 52.

[0066] When in use, on the surface circuit layer 3, the power module 8 provides current to the surface control circuit 311 through the surface power circuit 312, and the current flows through the surface control circuit 311 to the resistance wire 33 of the surface branch circuit area 32. When the current passes through the resistance wire 33, the current does work and consumes electric energy, generating heat in the resistance wire 33; on the bottom circuit layer 5, the power module 8 provides current to the bottom control circuit 511 through the bottom power circuit 512, and the bottom control circuit 511 transmits the generated current to the control copper sheet 52, and then outputs it through the copper sheet 52; due to the existence of the FPC matrix layer 4, the circuits between the surface circuit layer 3 and the bottom circuit layer 5 can operate independently without interfering with each other. Therefore, the utility model can obtain a flexible circuit board with two layers of circuits that can have different functions at the same time, operate independently, and do not interfere with each other.

[0067] Embodiment 2:

[0068] The basic content is the same as that of Example 1, except that: a first connection resistance wire 313 is arranged on the left side of the surface control circuit 311 and the surface power supply circuit 312, and a second connection resistance wire 314 is arranged on the right side of the surface control circuit 311 and the surface power supply circuit 312; the number of the resistance wires 33 is four, namely a first loop branch 331, a second loop branch 332, a third loop branch 333, and a fourth loop branch 334; the surface control circuit 311 is circuit-connected to one end of the first loop branch 331, and the other end of the first loop branch 331 is circuit-connected to the upper end of the first connection resistance wire 313, and the first connection The lower end of the resistance wire 313 is circuit-connected to one end of the second circular branch 332, and the other end of the second circular branch 332 is circuit-connected to the surface control circuit 311. At the same time, the surface control circuit 311 is circuit-connected to one end of the third circular branch 333, and the other end of the third circular branch 333 is circuit-connected to the lower end of the second connection resistance wire 314, the upper end of the second connection resistance wire 314 is circuit-connected to one end of the fourth circular branch 334, and the other end of the fourth circular branch 334 is circuit-connected to the surface control circuit 311; the first connection resistance wire 313 and the second connection resistance wire 314 are both circular structures.

[0069] When in use, the current passes through the surface control circuit 311 and flows to the resistor wires 33 of the first loop branch 331, the second loop branch 332, the third loop branch 333, and the fourth loop branch 334. The current generates heat due to the work done, so that the flexible circuit board has the function of generating heat.

[0070] Embodiment 3:

[0071] The basic content is the same as that of Example 1, except that: the number of the copper sheets 52 and the connection circuits 521 are both four, and they correspond one to one; a single copper sheet 52 is connected to one end of the corresponding connection circuit 521, and the other end of the connection circuit 521 is connected to the bottom power supply circuit 512. The copper sheet 52 includes a first rectangular area 522, a second rectangular area 523 and a grid area 524. The first rectangular area 522 and the second rectangular area 523 have the same structure, and the grid area 524 is evenly distributed with grid holes 525 that penetrate through. The exposed part of the copper sheet 52 relative to the corresponding window 63 is attached to the conductive TPU sheet 53 through a conductive double-sided adhesive.

[0072] When in use, the current flows to the four copper sheets 52 via the bottom control circuit 511, causing the copper sheets 52 to heat up; on this basis, the bottom control circuit 511 can also control the intermittent conduction of the current in the entire circuit, so that the copper sheets 52 flow through intermittent current, so that the receptors attached to the copper sheets 52 continue to feel the regular intermittent current stimulation; when the copper sheet 52 that is heated and continuously outputs intermittent current stimulation directly contacts the receptor, the receptor will have a strong sense of discomfort, so a conductive TPU sheet 53 is attached to the copper sheet 52, and the conductive TPU sheet 53 has a certain heat insulation effect on the heat generated by the copper sheet 52, and reduces the stimulation of the intermittent current continuously released by the copper sheet 52 on the receptor. Therefore, the utility model can not only generate heat energy, but also continuously release intermittent current stimulation; and it is more skin-friendly and comfortable.

[0073] Embodiment 4:

[0074] The basic content is the same as that of Embodiment 1, except that: the power module 8 includes an external power circuit board 81, a charging port 82 and a battery 83, and the external power circuit board 81 is circuit-connected with the charging port 82 and the battery 83; the battery 83 is circuit-connected with the surface power circuit 312 and the bottom power circuit 512 through the external power circuit board 81. The power supply 83 can be integrated on a flexible circuit board to make it smaller.

[0075] When in use, the charging port 82 is connected to an external power source to charge the battery 83, and the battery 83 provides power for the flexible circuit board; the charging port 82 can also be connected to an external power source to directly provide power for the flexible circuit board to work. Therefore, the utility model can provide two power supply modes, which is convenient for use in various scenarios and more portable.

[0076] The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiment. Any equivalent modifications or changes made by ordinary technicians in this field based on the contents disclosed in the present invention should be included in the protection scope recorded in the claims.

Claims

1. A flexible circuit board, characterized in that: The flexible circuit board comprises a component layer (1), a surface insulating coating (2), a surface circuit layer (3), an FPC matrix layer (4), a bottom circuit layer (5), and a bottom insulating coating (6) which are arranged in sequence from top to bottom; the lower surface of the surface insulating coating (2) is bonded to the upper surface of the FPC matrix layer (4) face to face, the lower surface of the FPC matrix layer (4) is bonded to the upper surface of the bottom insulating coating (6) face to face, the surface circuit layer (3) is sandwiched between the lower surface of the surface insulating coating (2) and the upper surface of the FPC matrix layer (4), and the bottom circuit layer (5) is sandwiched between the lower surface of the FPC matrix layer (4) and the upper surface of the bottom insulating coating (6); The upper half of the component layer (1) is a control circuit area (11), and the lower half is a power circuit area (12); the surface insulating coating (2) comprises a surface main board (21) and a plurality of surface support boards (22); the upper half of the surface main board (21) is a surface control area (211), and the lower half is a surface power area (212); the surface control area (211) is provided with a plurality of first holes (231), and the surface power area (212) is provided with a plurality of second holes (232); the surface circuit layer (3) is divided into a surface main circuit area (31) and a plurality of surface branch circuit areas (32); the upper half of the surface main circuit area (31) is a surface control circuit (311), and the lower half is a surface power circuit (312); the surface control circuit (311) is circuit-connected to the surface power circuit (312); the surface branch circuit area (32) is provided with resistance wires (33), and the resistance wires (33) are circuit-connected to the surface main circuit area (31); the FP The C substrate layer (4) comprises a substrate main board (41) and a plurality of substrate support boards (42); the upper portion of the substrate main board (41) is a substrate control area (411), and the lower portion is a substrate power supply area (412); the substrate control area (411) is provided with a plurality of first via holes (431), and the substrate power supply area (412) is provided with a plurality of second via holes (432); the bottom surface circuit layer (5) is divided into a bottom surface main circuit area (51) and a plurality of copper sheets (52); the bottom surface The upper half of the main circuit area (51) is a bottom control circuit (511), and the lower half is a bottom power circuit (512); the bottom control circuit (511) is circuit-connected to the bottom power circuit (512); the copper sheet (52) is circuit-connected to the bottom main circuit area (51) via a connecting circuit (521); the bottom insulating coating (6) comprises a bottom main board (61) and a plurality of bottom support plates (62); the bottom support plates (62) are provided with corresponding empty windows (63); The control circuit area (11) sequentially passes through the first hole (231) to contact the surface control circuit (311), and the power circuit area (12) sequentially passes through the second hole (232) to contact the surface power circuit (312); the control circuit area (11) sequentially passes through the first hole (231), the surface control circuit (311), and the first via hole (431) to contact the bottom control circuit (511), and the power circuit area (12) sequentially passes through the second hole (232), the surface power circuit (312), and the second via hole (432) to contact the bottom power circuit (512); the control circuit area (11) is circuit-connected to the surface control circuit (311). The power circuit area (12) is connected to the surface power circuit (312); the control circuit area (11) is connected to the bottom control circuit (511); the power circuit area (12) is connected to the bottom power circuit (512); the power circuit area (12) is connected to the power module (8); the surface support plate (22), the matrix support plate (42) and the bottom support plate (62) have the same area; the area of ​​the surface support circuit area (32) is less than or equal to the area of ​​the surface support plate (22); the empty window (63) corresponds to the copper sheet (52) from top to bottom, and the area of ​​the empty window (63) is less than or equal to the area of ​​the copper sheet (52).

2. A flexible circuit board according to claim 1, characterized in that: A first connection resistance wire (313) is arranged on the left side of the surface control circuit (311) and the surface power supply circuit (312), and a second connection resistance wire (314) is arranged on the right side of the surface control circuit (311) and the surface power supply circuit (312); The number of the resistance wires (33) is four, namely a first loop branch (331), a second loop branch (332), a third loop branch (333), and a fourth loop branch (334); The surface control circuit (311) is circuit-connected to one end of the first round-shaped branch (331), the other end of the first round-shaped branch (331) is circuit-connected to the upper end of the first connecting resistance wire (313), the lower end of the first connecting resistance wire (313) is circuit-connected to one end of the second round-shaped branch (332), the other end of the second round-shaped branch (332) is circuit-connected to the surface control circuit (311), and at the same time, the surface control circuit (311) is circuit-connected to one end of the third round-shaped branch (333), the other end of the third round-shaped branch (333) is circuit-connected to the lower end of the second connecting resistance wire (314), the upper end of the second connecting resistance wire (314) is circuit-connected to one end of the fourth round-shaped branch (334), and the other end of the fourth round-shaped branch (334) is circuit-connected to the surface control circuit (311); The first connection resistance wire (313) and the second connection resistance wire (314) are both of a meander-shaped structure.

3. A flexible circuit board according to claim 1, characterized in that: The number of the copper sheets (52) and the connection circuits (521) is four, and they correspond one to one; a single copper sheet (52) is circuit-connected to one end of its corresponding connection circuit (521), and the other end of the connection circuit (521) is circuit-connected to the bottom power supply circuit (512).

4. A flexible circuit board according to claim 1, 2 or 3, characterized in that: The copper sheet (52) comprises a first rectangular area (522), a second rectangular area (523) and a grid area (524); the first rectangular area (522) and the second rectangular area (523) have the same structure; and the grid area (524) is evenly distributed with penetrating grid holes (525).

5. A flexible circuit board according to claim 4, characterized in that: The exposed portion of the copper sheet (52) relative to the corresponding empty window (63) is connected to the conductive TPU sheet (53) by means of a conductive double-sided adhesive tape.

6. A flexible circuit board according to claim 1, 2 or 3, characterized in that: A program input area (34) is provided in the middle area between the surface control circuit (311) and the surface power supply circuit (312), and the program input area (34) comprises four program burning ports (341).

7. A flexible circuit board according to claim 1, 2 or 3, characterized in that: The power module (8) comprises an external power circuit board (81), a charging port (82) and a battery (83), and the external power circuit board (81) is circuit-connected to the charging port (82) and the battery (83); The battery (83) is respectively connected to the surface power circuit (312) and the bottom power circuit (512) via an external power circuit board (81).

8. A flexible circuit board according to claim 1, 2 or 3, characterized in that: A control area reinforcement sheet (71) and a power area reinforcement sheet (72) are affixed to the lower surface of the bottom main board (61); the control area reinforcement sheet (71) corresponds vertically to the control circuit area (11), and the power area reinforcement sheet (72) corresponds vertically to the power circuit area (12).

9. A flexible circuit board according to claim 8, characterized in that: Solder points (14) are distributed on the upper edge of the control circuit area (11); the solder points (14) sequentially pass through the first holes (231) to contact the surface control circuit (311); the solder points (14) sequentially pass through the first holes (231), the surface control circuit (311), and the first via holes (431) to contact the bottom control circuit (511); the solder points (14) are circuit-connected to the surface control circuit (311); and the solder points (14) are circuit-connected to the bottom control circuit (511).

10. The flexible circuit board according to claim 8, characterized in that: The material of the surface insulating coating (2) is polyimide, the material of the FPC matrix layer (4) is polyimide, and the material of the bottom insulating coating (6) is polyimide.

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