JPH0548320U - Common mode choke coil - Google Patents

Abstract

(57) [Summary] [Purpose] Achieving cost reduction by reducing the number of parts,
Parallel operation of semiconductor devices (especially high-speed switching operation)
It has excellent stability and high reliability. [Structure] A single high-permeability magnetic material 7 or 11 is used to form one circuit portion of a plurality of signal circuits with a pair of twisted wires, coaxial cables, or parallel wires so that the inductance of each circuit is equal. The signal circuit lines 8 and 12 of the same line length
In addition, a plurality of circuits are collectively wound.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a common mode choke coil, and particularly, in parallel operation of semiconductor elements, dv / dt generated during switching operation of each element (especially high speed switching operation) is reduced, and parallel operation is easy. The present invention relates to a common mode choke coil that can be made to have a uniform current sharing in each element.

[0002]

[Prior Art]

 FIG. 5 is a circuit diagram showing parallel operation of semiconductor devices using a conventional common mode choke coil.

In the figure, 1 is a semiconductor element such as a switching element, 2 is a drive circuit for the semiconductor element 1, 3a and 3b are signal lines for connecting the semiconductor elements 1 and the drive circuit 2 and transmitting signals, and 14a to 14d are Each connection piece of the common mode choke coil 18, 18 is a common mode choke coil, 19 is a straight capacitance (floating capacitance) existing on the circuit, and 20 is a voltage source simulating a change in voltage generated when the switching element is turned on and off. Is.

Next, the operation of this circuit will be described. A common mode noise current Io of I = C × dv / dt is generated from the voltage source 20 and the straight capacitance 19 when the switching element is on / off, which causes a circuit malfunction when the switching element is on / off. Therefore, the common mode choke coil 18 is usually inserted in the drive circuit section to suppress the common mode noise current of dv / dt and prevent circuit malfunction when the switching element is turned on and off. In particular, during high-speed switching operation, since dv / dt is large, the common mode choke coil 18 is indispensable because the common mode noise current Io becomes large even if the straight capacitance 19 is small.

Here, the common mode choke coil will be described. 6A is a front view showing the arrangement of components of a conventional common mode choke coil, FIG. 6B is a side view, FIG. 6C is a bottom view, and FIG. 6D is a circuit diagram.

In the figure, 14 is a connecting piece for connecting the common mode choke coil 18 to another circuit, 15 is a magnetic material, 16 is a signal circuit winding forming a desired inductance, and 17 is the magnetic material. It is a structure that holds and fixes the material 15 and the signal circuit winding 16. The characteristics of the common mode choke coil 18 are that the inductance in the normal mode is small and the inductance in the common mode is large.

FIG. 7A is a front view showing a component arrangement of a conventional common mode choke coil in which a signal circuit winding is a twisted wire, FIG. 7B is a bottom view, and FIG. 7C is a circuit diagram.

In the figure, 12 is a signal circuit winding formed by a twisted wire. The structure of the common mode choke coil 18 is substantially the same as that of the common mode choke coil 18 of FIG. 6, except that the signal circuit winding 12 is formed by a twisted wire to minimize the inductance in the normal mode. It makes a difference.

[0009]

[Problems to be solved by the device]

 The conventional common mode choke coil as described above suppresses the common mode noise current due to dv / dt during parallel operation of the semiconductor element 1 (especially during high speed switching operation), and causes current imbalance of each switching element. Had to be prevented. Therefore, each common mode choke coil is required to have the same characteristics and the same number as the semiconductor element 1.

Further, according to the calculation formula of the inductance of the toroidal coil, Φ = N × Io / Rm (1) Formula L = N × Φ / Io = N × N / Rm (2) Formula When parallel number = n , Lnl = L / n = N × N / (n × Rm) (3) Formula Io: Coil current L: Single inductance Lnl: N combined inductance Φ: Magnetic flux N: Number of turns Rm: Magnetic Resistance (constant). From the equation (3), when the number of parallel connections increases, the combined inductance Lnl becomes L / n. Therefore, in order to set the combined inductance Lnl = L, if the required number of turns is Nxl from the expressions (2) and (3), then Nxl × Nxl / Rm = N × N / (n × Rm) Nxl = √ [(N × N / Rm) / {1 / (n × Rm)}] = N × √n. Therefore, each common mode choke coil requires √n times the number of turns, which increases the work man-hour.

Further, due to the characteristics of each common mode choke coil, a ferrite-based mixed metal oxide is usually used as the magnetic material. However, due to an error in the material characteristics (the magnetic characteristic is usually about ± 20%), the individual choke coil is Since it is difficult to control the inductance value of the device, and the common mode choke coil is required for the number of parallel connections, there are problems to be solved such as an increase in the number of parts, an increase in the printed circuit board mounting area, and a decrease in reliability. It was

Therefore, the present invention reduces the number of parts of the common mode choke coil to achieve cost reduction, and stabilizes the parallel operation (especially, high-speed switching operation) of semiconductor elements, for example, prevents malfunction of each element, It is an object to provide a highly reliable common mode choke coil which is excellent in equalizing current balance and the like.

[0013]

[Means for Solving the Problems]

 The common mode choke coil according to the present invention comprises one of a pair of twisted wires, a coaxial cable, and a parallel wire, and has the same wire length so that the inductance of each circuit is equalized for a plurality of circuits collectively. Signal circuit winding, and a single high-permeability magnetic material body in which a plurality of circuit portions of the signal circuit winding are collectively wound, the high-permeability magnetic material body and the signal circuit winding. It comprises a structure for holding and fixing the wire and a connecting piece connected to each end of each of the signal circuit windings.

[0014]

[Action]

 In the common mode choke coil of the present invention, a single high-permeability magnetic material body is used to form one circuit portion for a plurality of signal circuits by a pair of twisted wires, coaxial cables, or parallel wires. Since the windings are bundled together, the inductance in the normal mode is minimized, and the length of each signal circuit winding is set to the same wiring length. In addition, since multiple signal circuits are wound together on a single high-permeability magnetic material body, a conventional common mode choke coil in which one circuit is wound on a single magnetic material is used. On the other hand, the desired inductance can be obtained even if the number of turns is reduced.

[0015]

【Example】

 Embodiments of the present invention will be described below.

FIG. 1 is a circuit diagram showing parallel operation of semiconductor devices using a common mode choke coil according to an embodiment of the present invention, and FIG. 2 is a signal circuit of a common mode choke coil according to an embodiment of the present invention. It is a winding figure which shows a winding method. In the figure, the same reference numerals and symbols as those of the above conventional example indicate the same or corresponding components as those of the above conventional example.

In the figure, reference numeral 4 is a common mode choke coil, and 6a to 6p are connecting pieces for connecting the common mode choke coil 4 to other circuits. In this embodiment, the signal circuit winding of each common mode choke coil 4 is wound as shown in FIG.

In the winding method of FIG. 2A, a twisted wire for one circuit is twisted for four circuits at the same time to perform a batch winding, and the wiring length for four circuits is set to be an equal length, and The number of turns required to form a desired inductance is wound around the magnetic permeability magnetic material 7. The colors of the respective signal circuit lines 8 are all separately coded. For example, the signal circuit line connecting the connection piece 6a and the connection piece 6i is black, and the signal circuit line connecting the connection piece 6b and the connection piece 6j is connected. The line is light blue, the signal circuit line connecting the connection piece 6c and the connection piece 6k is brown, the signal circuit line connecting the connection piece 6d and the connection piece 6l is green, and the signal circuit line connecting the connection piece 6e and the connection piece 6m is Purple, the signal circuit line connecting the connecting piece 6f and the connecting piece 6n is red, the signal circuit line connecting the connecting piece 6g and the connecting piece 6o is blue, and the signal circuit line connecting the connecting piece 6h and the connecting piece 6p is yellow. There is.

In the winding method of FIG. 2B, the twisted wire for one circuit is twisted for two circuits, and the twisted wire for four circuits is further twisted in a batch to form a wiring length for four circuits. Is a uniform length, and the number of turns required to form a desired inductance is wound around a single high-permeability magnetic material 7. It should be noted that the colors of the respective signal circuit windings 12 are all separately classified as in the case of FIG.

Next, the common mode choke coil of this embodiment will be described. FIG. 3A is a front view showing a component arrangement of a common mode choke coil in which the shape of the high-permeability magnetic material according to the embodiment of the present invention is EE type or EI type, and FIG. 3B is a bottom view. is there. In the figure, the same reference numerals and symbols as those of the above-mentioned conventional example indicate the same or corresponding components as those of the above-mentioned conventional example.

In the figure, 6 is a connecting piece for connecting the signal circuit wire 8 for four circuits to another circuit, 7 is a high magnetic permeability magnetic material, and 8 is a signal circuit winding forming a desired inductance. , 9 are structures for holding and fixing the high-permeability magnetic material 7 and the signal circuit lines 8 for four circuits. The high-permeability magnetic material 7 has a shape of EE type or EI type, and the signal circuit lines 8 for four circuits are collectively wound by the winding method shown in FIG.

FIG. 4A is a plan view showing a component arrangement of a common mode choke coil in which the high-permeability magnetic material according to an embodiment of the present invention is a toroidal type, and FIG. 4B is a side view. ..

In the figure, 10 is a common mode choke coil, 11 is a high-permeability magnetic material, 12 is a signal circuit winding formed by a twisted wire, 13 is the high-permeability magnetic material 11 and a signal circuit wire 12 Is a structure for holding and fixing. The high-permeability magnetic material 11 has a toroidal shape, and four signal circuit lines 12 are wound around the outer circumference of the toroidal-type high-permeability magnetic material 11. The signal circuit winding 12 for one circuit is composed of a twisted wire and is equally divided into four circuits by the winding method shown in FIG. 2 (b). The number of turns required to form the desired inductance is wound around the outer circumference of the magnetic material 11.

As described above, the common mode choke coil of the present embodiment is composed of one of a pair of twisted wires, a coaxial cable, and a parallel wire, and a plurality of circuits are collectively packaged so that the inductance of each circuit is uniform. Signal circuit windings 8 and 12 having the same wire length, and a single high magnetic permeability material 7 and 11 in which a plurality of circuit portions of the signal circuit windings 8 and 12 are collectively wound. Connected to the body, structures 9 and 13 for holding and fixing the high-permeability magnetic material 7 and 11 and the signal circuit windings 8 and 12, and the terminals of the signal circuit windings 8 and 12, respectively. It is provided with connecting pieces 6a to 6p.

That is, in the common mode choke coil of this embodiment, one circuit of a plurality of signal circuits is formed by a pair of twisted wires, coaxial cables, or parallel wires in a single high magnetic permeability magnetic material 7, 11. The windings are formed to have the same wire length so that the inductances of the circuits are equalized, and the windings for a plurality of circuits are collectively formed.

Therefore, by minimizing the inductance in the normal mode and making the signal circuit winding lengths the same, the inductance in the normal mode becomes uniform.

Further, since a plurality of signal circuits are collectively wound on a single high-permeability magnetic material, the magnetic flux Φn at the time of winding n circuits is calculated by the formula (1) of the toroidal coil. ) From the formula, Φn = n × (N × Io / Rm) (4) Formula Ln2 is Ln2 = N × Φn / (n × Io) = (N / n × Io) × (n × N × Io / Rm) = N × N / Rm (5) In contrast to Lnl = N × N / (n × Rm) in the equation (3), the equation (5) is Ln2 = N × N / Rm. In order to set the combined inductance Ln2 = Ln1, if the number of turns required from equations (3) and (5) is Nx2, then N × N / (n × Rm) = Nx2 × Nx2 / Rm Nx2 = √ [ {N × N / (n × Rm)} / (1 / Rm)] = N × √n. Therefore, by collectively winding a plurality of signal circuit windings 8 on a single high magnetic permeability magnetic material 7, a common mode choke coil 18 in which one circuit is wound on a conventional single magnetic material 15 is formed. On the other hand, the desired inductance can be obtained even if the number of turns is reduced by 1 / √n.

For this reason, the number of turns of the signal circuit line 8 is reduced, so that the size of the common mode choke coil can be reduced, and moreover, the winding is made up of a plurality of circuits at a time, the number of parts can be reduced, and the cost can be reduced. Becomes

Further, since the inductances in the normal mode are equalized, dv / dt generated during parallel operation (especially, high-speed switching operation) of the plurality of semiconductor elements 1 can be reduced, and parallel operation can be facilitated. The current distribution of each element can be made equal, the reliability is improved, and it becomes a high-performance common mode choke coil.

Moreover, in the above-described embodiment, since the colors of the plurality of signal circuit lines 8 and 12 are all separated separately, each signal line can be identified by its appearance (on the outer surface). Therefore, erroneous wiring can be prevented, inspection is facilitated, and workability and reliability are improved.

In addition, in the above embodiment, the connection pieces 6a to 6p are connected to the ends of the plurality of signal circuit lines 8 and 12, and are directly mounted on the printed board as a single common mode choke coil. be able to. Therefore, the mounting area of the printed circuit board can be reduced, the assembly time can be shortened, and the cost can be reduced.

By the way, in the above embodiment, the common mode choke coils of the signal circuit windings 8 and 12 in which four circuits are integrated are described, but the number of circuits may be increased or decreased, and the number of other components may be increased. The shape and dimensions may be arbitrarily modified or changed as long as the same effect as the present invention can be obtained even if the above is changed.

[0033]

[Effect of the device]

 As described above, the common mode choke coil of the present invention includes the signal circuit winding, the single high-permeability magnetic material body, the structure, and the connecting piece, and is a single high-permeability magnetic material body. Each signal circuit is composed of a pair of twisted wires, coaxial cables, or parallel wires, and the wires are collectively wound to minimize the inductance in normal mode and By making the circuit wiring length the same, the inductance in the normal mode becomes uniform, and the desired inductance can be obtained even if the number of turns is reduced compared to the conventional common mode choke coil. As a result, not only can the size of the common mode choke coil be promoted, the number of parts can be reduced, which not only reduces costs, but also when semiconductor devices are operated in parallel (especially high-speed switches). Stability and reliability of the packaging operation) is improved.

[Submission date] February 28, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction content]

In the figure, 1 is a semiconductor element such as a switching element, 2 is a drive circuit for the semiconductor element 1, 3a and 3b are signal lines for connecting the semiconductor elements 1 and the drive circuit 2 and transmitting signals, and 14a to 14d are Each connection piece of the common mode choke coil 18, 18 is a common mode choke coil, 19 is a stray capacitance (stray capacitance) existing on the circuit, and 20 is a voltage source simulating a change in voltage generated when the switching element is turned on and off. .

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction content]

Next, the operation of this circuit will be described. A common mode noise current Io of I = C × dv / dt is generated from the voltage source 20 and the stray capacitance 19 when the switching element is turned on and off, which causes a circuit malfunction when the switching element is turned on and off. Therefore, normally, the common mode choke coil 18 is inserted in the drive circuit section to suppress the common mode noise current of dv / dt and prevent circuit malfunction when the switching element is turned on and off. In particular, during high-speed switching operation, since dv / dt is large, the common mode noise current Io is large even if the stray capacitance 19 is small, and the common mode choke coil 18 is essential.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction content]

In the winding method of FIG. 2A, a twisted wire for one circuit is twisted for four circuits at the same time to perform a batch winding, and the wiring length for four circuits is set to be an equal length, and The number of turns required to form a desired inductance is wound around the magnetic permeability magnetic material 7. Contact name, the color of the signal circuit windings 8 are color all separately, for example, the signal circuit winding black connecting the connection pieces 6i and the connecting piece 6a, signal circuits connecting the connecting piece 6b and the connecting piece 6j winding blue, the signal circuit winding brown connecting the connection piece 6c and the connecting piece 6k, the signal circuit winding connecting the connecting piece 6d and the connecting piece 6l green signal times Michimaki connecting the connection piece 6e and the connection piece 6m line purple, red connection piece 6f the connecting piece signal circuit winding connecting 6n, the signal circuit winding connecting the connecting piece 6g connection segment 6o blue signal times Michimakisen connecting the connection piece 6h and the connection piece 6p Is yellow.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction content]

In the figure, 6 is a connecting piece for connecting the signal circuit winding 8 for 4 circuits to another circuit, 7 is a magnetic material with high magnetic permeability, 8 is a signal circuit winding forming a desired inductance, Reference numeral 9 is a structure for holding and fixing the high-permeability magnetic material 7 and the signal circuit winding 8 for four circuits. The high-permeability magnetic material 7 has a shape of EE type or EI type, and the signal circuit windings 8 for four circuits are collectively wound by the winding method shown in (a) or (b) of FIG. ing.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Name of item to be corrected] 0023

[Correction method] Change

[Correction content]

In the figure, 10 is a common mode choke coil, 11 is a toroidal type high magnetic permeability magnetic material , 12 is a signal circuit winding formed by a twisted wire, and 13 is the high magnetic permeability magnetic material 11 and a signal circuit winding. It is a structure for holding and fixing the wire 12. Signal times Michimakisen 12 will know 4 circuit, the winding length of each circuit line number of turns required to form a desired inductance on the outer periphery of a single torroid type high-permeability magnetic material 11 as a uniform length Is wound.

[Procedure Amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction content]

For this reason, the number of turns of the signal circuit winding 8 is reduced, so that it is possible to promote the downsizing of the common mode choke coil, and the winding is made up of a plurality of circuits at a time. Becomes

[Procedure Amendment 7]

[Document name to be amended] Statement

[Name of item to be corrected] 0030

[Correction method] Change

[Correction content]

Moreover, in the above-described embodiment, since the colors of the plurality of signal circuit windings 8 and 12 are all separated separately, each signal line can be identified by its appearance (on the outer surface). Therefore, erroneous wiring can be prevented, inspection is facilitated, and workability and reliability are improved.

[Procedure Amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0031

[Correction method] Change

[Correction content]

In addition, in the above embodiment, the connection pieces 6a to 6p are connected to the end portions of the plurality of signal circuit windings 8 and 12, and are directly mounted on the printed board as a single common mode choke coil. be able to. Therefore, the mounting area of the printed circuit board can be reduced, the assembly time can be shortened, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing parallel operation of semiconductor devices using a common mode choke coil according to an embodiment of the present invention.

FIG. 2 is a winding diagram showing a signal circuit winding method of a common mode choke coil according to an embodiment of the present invention.

FIG. 3 (a) is a front view showing a component arrangement of a common mode choke coil in which a high-permeability magnetic material according to an embodiment of the present invention is EE type or EI type;
Is a bottom view.

FIG. 4 (a) is a plan view showing a component arrangement of a common mode choke coil having a toroidal type high permeability magnetic material according to an embodiment of the present invention, and FIG. 4 (b) is a side view. is there.

FIG. 5 is a circuit diagram showing parallel operation of semiconductor elements using a conventional common mode choke coil.

6A is a front view showing the arrangement of components of a conventional common mode choke coil, FIG. 6B is a side view, and FIG.
Is a bottom view and (d) is a circuit diagram.

7A is a front view showing a component arrangement of a conventional common mode choke coil in which a signal circuit winding is a twisted wire, FIG. 7B is a bottom view, and FIG. 7C is a circuit diagram. .

[Explanation of symbols]

 1 semiconductor element 2 drive circuit 3a, 3b signal line 4,10 common mode choke coil 6,6a-6p connecting piece 7,11 high magnetic permeability magnetic material 8,12 signal circuit line 9,13 structure 19 straight capacitance 20 voltage source

[Procedure amendment]

[Submission date] February 28, 1992

[Procedure Amendment 9]

[Document name to be amended] Statement

[Correction target item name] Explanation of code

[Correction method] Change

[Correction content]

[Explanation of reference numerals] 1 semiconductor element 2 drive circuit 3a, 3b signal line 4,10 common mode choke coil 6,6a to 6p connection piece 7,11 high magnetic permeability magnetic material 8,12 signal circuit winding 9,13 structure 19 Stray capacitance 20 Voltage source

Claims (1)

[Scope of utility model registration request] 1. A signal circuit comprising one of a pair of twisted wires, a coaxial cable, and a parallel wire, and a plurality of circuits are collectively formed into a coil having the same wire length so that the inductances of the circuits are equalized. A winding, a single high-permeability magnetic material body in which a plurality of circuits of the signal circuit winding are collectively wound, and a structure for holding and fixing the high-permeability magnetic material body and the signal circuit winding. And a connection piece connected to each terminal of each of the signal circuit windings.