CN205028753U - Ultra-small SMD network port transformer - Google Patents

Abstract

The utility model discloses an ultra-small patch-type network port transformer, including an I-shaped core, a plate-shaped core and a winding group. The I-shaped core has a winding core portion located in the middle position and a first flange portion and a second flange portion respectively located at both ends of the winding core portion. The two ends of the plate-shaped core are respectively fixed to the bottom surfaces of the first flange portion and the second flange portion to form a closed magnetic circuit with the I-shaped core. The first flange portion and the second flange portion are provided with a plurality of equal pads. The winding of the winding group is wound on the winding core portion and one end is connected to the pad on the first flange portion and the other end is connected to the pad on the second flange portion. The flange portions at both ends of the I-shaped core of the utility model directly adopt electroplated pads, which are matched with winding welding, and the structure is simplified, easy to process, and low in cost.

Description

Ultra-small SMD network port transformer

technical field

The utility model relates to a network port transformer, in particular to an ultra-small patch type network port transformer.

Background technique

Ethernet is the foundation of the Internet widely used at present, and it is also the mainstream form of LAN at present. RJ45 is a standard interface for Ethernet wired connection. It is not only standard equipped on IT equipment such as computers, but also standard equipped on various AV and smart home equipment represented by smart TV, video surveillance, and home multimedia. The network port transformer is a key component applied to the LAN interface line. While transmitting Ethernet signals at high speed, it also plays the role of electrical isolation of signal output and input terminals, impedance matching, and common mode noise suppression.

Due to the redundant structure of existing network port transformers, the production process is complicated and the mold opening requirements are high, which leads to increased costs, and the increased costs are passed on to consumers, which needs further improvement, such as Chinese patent-application number 201320389259.0 For pulse transformers, the flanges at both ends of the drum core need to be assembled and fixed with a plurality of scattered electrode sheets one by one, and then the winding wires are welded to the electrode sheets. The cost of the electrode sheets and the assembly, fixing, and welding processes lead to an increase in cost. In addition, the winding of the winding core is a two-layer winding. Since the winding position of the winding core of the drum core and the flange are two planes perpendicular to each other, when winding the second layer of wire, the lead wire of the first layer The portion to the pad will affect the wiring at the beginning and end of the second layer.

Contents of the invention

In order to solve the above-mentioned technical problems, the purpose of this utility model is to provide an ultra-small SMD network interface transformer with simple structure and easy processing.

The technical scheme that the utility model adopts is:

The ultra-small SMD network port transformer includes an I-shaped core, a plate-shaped core and a winding group. The I-shaped core has a winding core in the middle and a first flange and a second Flange part, the two ends of the plate-shaped core are respectively fixed to the bottom surface of the first flange part and the second flange part to form a closed magnetic circuit with the I-shaped core, and it is characterized in that: the first flange part and the second flange part The flange part is provided with a number of welding pads of the same amount, and the winding wire of the winding group is wound on the winding core part, and one end is connected to the pad on the first flange part, and the other end is connected to the second flange part. pads.

Further, the opposite inner walls of the first flange part and the second flange part are respectively provided with inclined surfaces, and the inclined surfaces extend from the top surfaces of the first flange part and the second flange part to the winding core part.

Specifically, there are four pads on the first flange part, which are respectively a first pad and a second pad located at one end of the first flange part and conducting, and a pad located at the other end of the first flange part. The third pad and the fourth pad;

There are four welding pads on the second flange part, which are respectively the fifth welding pad and the sixth welding pad located at one end of the second flange part and conducting, and the seventh welding pad located at the other end of the second flange part. pad and the eighth pad;

The winding group includes a first winding, a second winding, a third winding, and a fourth winding, both ends of the first winding are respectively connected to the first pad and the eighth pad, and the second winding The two ends of the wire are respectively connected to the second pad and the seventh pad, the two ends of the third winding are respectively connected to the third pad and the sixth pad, and the two ends of the fourth winding are respectively connected to the fourth pad , the fifth pad.

Wherein, the first winding and the fourth winding are wound in parallel on the winding core without intersecting and serve as the first layer of coils, and the second and third windings are parallel and not intersecting on the first layer of coils Wind up and act as a second coil.

Further, both ends of the first pad, the second pad, the third pad, the fourth pad, the fifth pad, the sixth pad, the seventh pad and the eighth pad are provided with positioning pads. gap.

Furthermore, the positions of the second pad, the third pad, the fourth pad, the sixth pad, the seventh pad and the eighth pad are higher than the first pad and the fifth pad and the pads A positioning groove connecting the two ends of the pad is opened in the middle of the top.

Preferably, the distance between the second pad and the third pad, and between the sixth pad and the seventh pad is greater than 1.5mm, and the I-shaped core and the plate-shaped core adopt a magnetic permeability greater than 1800ui magnetic material, and its volume resistivity is greater than Ωm.

Further, the four inner corner ends of the plate-shaped core in contact with the first flange part and the second flange part are fixed by glue.

The beneficial effects of the utility model:

The flanges at both ends of the I-shaped core of the utility model directly adopt electroplating pads, cooperate with winding welding, the structure is simplified, easy to process, and the cost is low, and the coiling core part and the flange part adopt inclined surfaces, so as to avoid When bending the second layer lead wire, the part from the lead wire of the first layer to the pad will affect the wiring at the beginning and end of the second layer.

Description of drawings

Below in conjunction with accompanying drawing, the specific embodiment of the present utility model is described further.

Fig. 1 is the three-dimensional view of the network interface transformer of the present utility model;

Fig. 2 is an exploded view of the I-shaped core and the plate-shaped core;

Fig. 3 is the top view of I core;

Fig. 4 is the side view of I core;

Fig. 5 is a state diagram of an unfinished primary winding of the network interface transformer of the present invention;

Fig. 6 is a state diagram of the completed primary winding of the network interface transformer of the present invention;

Fig. 7 is a state diagram of the unfinished secondary winding of the network interface transformer of the present invention;

Fig. 8 is a state diagram of the completed secondary winding of the network port transformer of the present invention.

detailed description

Referring to Fig. 1 and Fig. 2, it is an ultra-small chip-type network port transformer of the present invention, including an I-shaped core 1, a plate-shaped core 2 and a winding group 3, and the I-shaped core 1 has a coil located in the middle The core 11 and the first flange 12 and the second flange 13 respectively located at the two ends of the core 11. Fixed to form a closed magnetic circuit with the I-shaped core 1.

In particular, the size of the I-shaped core 1 is not larger than 4.7x3.6x2.0mm, and the size of the plate-shaped core 2 is not larger than 4.7x3.6x1.0mm. This is an example without limitation. The gap between the I-shaped core 1 and the plate-shaped core 2 is less than 0.01 mm, which can close the magnetic circuit, reduce magnetic field leakage to interfere with nearby components, and increase the inductance value of the entire product.

The first flange part 12 and the second flange part 13 are respectively provided with four welding pads 4, and the winding wires of the winding group 3 are wound on the winding core part 11 and one end is connected to the first flange part 12. The other end of the pad 4 is connected to the pad 4 on the second flange portion 13. Compared with the traditional electrode sheet form, the pad 4 is directly plated and welded with wire winding. The structure is simplified, easy to process, and low in cost.

The inner side walls of the first flange portion 12 and the second flange portion 13 are respectively provided with inclined surfaces 14 with an inclination angle of at least 15°. The top surface extends to the winding core 11 , so that when the lead wires of the first layer are bent, the lead wires to the pads will not affect the wiring at the beginning and end of the second layer.

In addition, after the I-shaped core 1 and the plate-shaped core 2 are assembled facing each other, the four inner corners of the plate-shaped core 2 that are in contact with the first flange portion 12 and the second flange portion 13 are fixed with glue 17 .

As shown in FIG. 3 and FIG. 4 , there are four pads 4 on the first flange portion 12 , which are respectively a first pad A and a second pad B located at one end of the first flange portion 12 and conducting, And the third pad C and the fourth pad D located at the other end of the first flange portion 12;

Similarly, there are four pads 4 on the second flange portion 13, which are respectively the fifth pad E and the sixth pad F located at one end of the second flange 13 and conducting, and the pads located on the second flange The seventh pad G and the eighth pad H at the other end of part 13;

In order to facilitate the fixed winding, the first pad A, the second pad B, the third pad C, the fourth pad D, the fifth pad E, the sixth pad F, the seventh pad G and Both ends of the eighth pad H are provided with positioning notches 15 .

The positions of the second pad B, the third pad C, the fourth pad D, the sixth pad F, the seventh pad G and the eighth pad H are higher than the first pad A and the fifth pad E At least 0.2mm. There are two reasons for the design here. One is to facilitate fixing the coil leads. The other is to avoid the lead movement of the first pad A and the fifth pad E from moving too close to the pads B and F, and Intersect with the leads of pads B and F, affecting the insulation performance of the transformer. Moreover, a positioning groove 16 connecting the two ends of the pad is provided at the middle position of the top of the pad, which is beneficial to center each wire on the pad during winding, and facilitates the subsequent welding process. .

Preferably, the distances between the second pad B and the third pad C, and between the sixth pad F and the seventh pad G are all greater than 1.5 mm, and the I-shaped core 1 and the plate-shaped core 2 Use a magnetic material with a magnetic permeability greater than 1800ui, and its volume resistivity is greater than Ωm. This requirement is because the pads at both ends are respectively connected to the primary coil winding and secondary coil winding of the transformer. Since the transformer has an important isolation and insulation function , this distance will ensure that the network port transformer meets the requirements of IEEE802.3 for electrical insulation. The volume resistivity of the required magnetic material is greater than Ωm, so the safety distance of at least 1.5 mm is effective. If the resistivity is greater than Ωm, the requirement for the safety distance can be reduced.

Correspondingly, as shown in FIGS. 5-8 , the winding set 3 includes a first winding a, a second winding b, a third winding c, and a fourth winding d.

The first winding a and the fourth winding d are wound on the winding core 11 in parallel without intersecting and serve as the first layer of coils. The two ends of the first winding a are respectively connected to the first pad A, the eighth The bonding pad H, the two ends of the fourth winding d are respectively connected to the fourth bonding pad D and the fifth bonding pad E.

The second winding b and the third winding c are wound on the first layer coil in parallel without intersecting and serve as the second layer coil, and the two ends of the second winding b are respectively connected to the second pad B, the seventh pad G, the two ends of the third winding c are respectively connected to the third pad C and the sixth pad F.

The above is only the preferred implementation of the utility model, the utility model is not limited to the above implementation, as long as the technical solutions to achieve the purpose of the utility model by basically the same means are within the scope of protection of the utility model.

Claims (8)

1. An ultra-small SMD network port transformer, including an I-shaped core (1), a plate-shaped core (2) and a winding group (3). The I-shaped core (1) has a winding core (11) in the middle ) and the first flange part (12) and the second flange part (13) respectively located at both ends of the roll core part (11), the two ends of the plate-shaped core (2) are respectively connected to the first flange part (12) . The bottom surface of the second flange part (13) is fixed to form a closed magnetic circuit with the I-shaped core (1), and it is characterized in that: the first flange part (12) and the second flange part (13) are provided with etc. The number of pads (4), the winding wire of the winding group (3) is wound on the winding core (11) and one end is connected to the pad (4) on the first flange (12) and the other One end is connected to the pad (4) on the second flange portion (13). 2. The ultra-small SMD network port transformer according to claim 1, characterized in that: the inner side walls of the first flange part (12) and the second flange part (13) are respectively provided with inclined A surface (14), the inclined surface (14) extends from the top surfaces of the first flange portion (12) and the second flange portion (13) to the winding core portion (11). 3. ultra-miniature patch type network port transformer according to claim 1, is characterized in that: There are four welding pads (4) on the first flange part (12), which are respectively the first welding pad (A) and the second welding pad (A) located at one end of the first flange part (12) and conducting B), and the third pad (C) and the fourth pad (D) located at the other end of the first flange portion (12); There are four welding pads (4) on the second flange part (13), which are the fifth welding pad (E) and the sixth welding pad ( F), and the seventh pad (G) and the eighth pad (H) located at the other end of the second flange portion (13); The winding group (3) includes a first winding (a), a second winding (b), a third winding (c), and a fourth winding (d), the first winding (a) The two ends are respectively connected to the first pad (A) and the eighth pad (H), and the two ends of the second winding (b) are respectively connected to the second pad (B) and the seventh pad (G). The two ends of the third winding (c) are respectively connected to the third pad (C) and the sixth pad (F), and the two ends of the fourth winding (d) are connected to the fourth pad (D) and the sixth pad (D) respectively. Five pads (E). 4. The ultra-small SMD network port transformer according to claim 3, characterized in that: the first winding (a) and the fourth winding (d) are parallel and do not cross each other on the winding core (11) Wound and used as a first-layer coil, the second winding (b) and the third winding (c) are wound on the first-layer coil in parallel without intersecting and used as a second-layer coil. 5. The ultra-small SMD network port transformer according to claim 3, characterized in that: the first pad (A), the second pad (B), the third pad (C), the fourth pad Positioning notches (15) are provided at both ends of the pad (D), the fifth pad (E), the sixth pad (F), the seventh pad (G) and the eighth pad (H). 6. The ultra-small SMD network port transformer according to claim 3 or 5, characterized in that: the second pad (B), the third pad (C), the fourth pad (D), The positions of the sixth pad (F), the seventh pad (G) and the eighth pad (H) are higher than the first pad (A) and the fifth pad (E), and there is a The positioning grooves (16) at both ends of the connecting pad are connected. 7. The ultra-small SMD network port transformer according to claim 3, characterized in that: between the second pad (B) and the third pad (C), and the sixth pad (F) The distances to the seventh pad (G) are both greater than 1.5 mm, and the I-shaped core (1) and the plate-shaped core (2) are made of magnetic materials with a magnetic permeability greater than 1800ui, and their volume resistivity is greater than Ωm. 8. The ultra-small SMD network port transformer according to claim 3, characterized in that: the plate-shaped core (2) is in contact with the first flange part (12) and the second flange part (13) The four inner corners of the end are fixed with colloid (17).