JPH04290001A - Electronic circuit board - Google Patents

Abstract

PURPOSE:To devise a characteristic impedance of a film signal transmission line to be made variable and also to make the circuit configuration compact. CONSTITUTION:At least part of film signal transmission lines 2a, 2b is made of a resistive material in the electronic circuit board in which an insulation board main body 1 and the film signal transmission lines 2a, 2b provided on a major side of the insulation board main body 1. That is, the entire film signal transmission lines or the major part including a resistor 10 connected in series between the film signal transmission lines, a reactance element and an inductance adjustment section arranged at the side is made of a so-called resistive material. Thus, the required characteristic impedance is kept without changing the width or the length of the film signal transmission lines and high circuit density (high density pattern) is attained and a guide wavelength is decreased.

Description

[Detailed description of the invention]

[Object of the invention]

0002

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic circuit board, and more particularly to an electronic circuit board suitable for constructing a high frequency circuit device.

0003

[Background Art] As information becomes more sophisticated and the amount of information increases, signal frequencies also become higher. For example, in the field of mobile communication such as mobile telephones, high frequency circuit devices in the high frequency (microwave) band are being used. be. Furthermore, for the purpose of making high frequency circuit devices lighter, thinner, shorter, and more compact, a configuration has been adopted in which a required high frequency circuit is disposed on the surface of an insulating substrate made of ceramic as a base material, for example.

By the way, in the construction of this type of high frequency circuit device, an electronic circuit board having the following construction is generally used. That is, as shown in perspective in FIG. 5, a film-type signal transmission line 2 having a microstrip line structure, for example, is formed on one main surface of an insulating substrate body 1 made of, for example, alumina and having a dielectric constant of about 10. An electronic circuit board is used in which a grounding conductor layer 3 is integrally formed on the other main surface of an insulating substrate body 1. However, in this type of electronic circuit board, the characteristic impedance is 50Ω.
In the case of a film-type signal transmission line 2, the width W of the film-type signal transmission line 2 is set to approximately 0.635 μm, the thickness of the insulating substrate body 1 is set to approximately 0.635 mm, and the characteristic impedance is set to 1 kΩ. In order to achieve this, it is necessary to set the width W of the film-type signal transmission line 2 even narrower. Also,
In order to provide the required circuit function, a resistor chip 4 (thick film circuit board ) or a film resistor 5 (in the case of a thin film circuit board) is inserted and arranged, and in the case of a configuration in which a bias is applied to the signal transmission line 2a of a microstrip line structure, a film reactance element 6 is arranged. There is. In FIG. 8, 7 indicates a bare chip, 8 indicates a pad portion connected to the grounding conductor layer 3, and 9 indicates a lead wire.

In the structure of the electronic circuit board, the film-type signal transmission line 2 is generally made of an Au conductor, an Ag--Pd conductor, or a Cu conductor, and the film-type resistor is made of a commercially available paste.

[0006]

However, the electronic circuit board having the above structure has the following practical problems. First of all, when providing a high impedance to the film-type signal transmission line 2 having a microstrip line structure in an electronic circuit board, it is necessary to reduce the width W of the signal transmission line 2. However, since there is a limit to the narrowing of the width W of the membrane signal transmission line 2, it is necessary to use a material with a small dielectric constant ε as the insulating substrate body 1 or to increase the thickness of the insulating substrate body 1. do not have. Here, the membrane type signal transmission line 2 width W
There is also the problem that when the area is narrowed, electromagnetic waves are likely to be dissipated from the corners of the connected ends, which are enlarged to maintain connections with resistors and the like.

Second, when the characteristic impedance (Zo) of the membrane signal transmission line 2 and the load resistance (ZR) are not matched (different), an equivalent reactance element is formed at a specific frequency. For example, as schematically shown in FIG. 9, the characteristic impedance Z of the membrane signal transmission line 2
When o = 50Ω, the length L of the membrane signal transmission line 2 is:
Zin=0(for the frequency where L=(2n+1)λg/4 (where n is an integer)
Ω), but the length L of the membrane signal transmission line 2 is always constant and cannot be shortened. In other words, from the viewpoint of the membrane signal transmission line 2, high density cannot be achieved.

Thirdly, when the resistor 4 (5) is arranged in series between the membrane signal transmission lines 2a and 2b for transmitting high-frequency signals, the membrane signal transmission line 2a is used to match the pattern.
, 2b and the width W1 of the resistor 4 (5), R = l/W1 ・Rs (sheet resistance value...where l is the length of the resistor), the resistance value is adjusted to adjust the resistance. Increasing the resistor 4 (5) requires increasing the length of the resistor 4 (5), which also impedes the ability to make the circuit compact.

The present invention has been made in response to the above-mentioned circumstances, and provides an electronic circuit board that not only allows changing the characteristic impedance of the membrane signal transmission line 2, but also allows the circuit configuration to be made more compact. For the purpose of providing.

[Configuration of the invention]

[0011]

[Means for Solving the Problems] An electronic circuit board according to the present invention includes an insulating substrate body and a film-type signal transmission line provided on the main surface of the insulating substrate body. , at least a portion of the film-type signal transmission line is formed of a resistive material. That is, the electronic circuit board of the present invention includes the entire film-type signal transmission line, including the resistor connected in series between the film-type signal transmission lines, and the reactance element and inductance adjustment unit arranged in a side chain. The main idea is to construct the main part from a so-called resistant material.

0012

[Operation] According to the above structure, at least a part of the film-type signal transmission line is composed or formed of a so-called resistive material, so compared to a case where it is formed of a normal conductor,
Not only can the characteristic impedance be easily increased, but it can also be made lighter, thinner, and smaller. In other words, it is possible to maintain the required characteristic impedance without changing the width or length of the film-type signal transmission line, and it is possible to achieve higher circuit density (higher pattern density). It exhibits the function of being able to make it smaller.

[0013]

Embodiments An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

FIG. 1 is a plan view showing an example of the main part configuration of an electronic circuit board according to the present invention, in which 1 is an insulating substrate body, 2 is an insulating substrate body;
is a film-type signal transmission line with a microstrip line structure provided on one main surface of the insulating substrate body 1. As shown in FIG. Therefore, the membrane-type signal transmission line 2 is divided into two membrane-type signal transmission lines 2a and 2b, and a resistor 10 is connected in series between the membrane-type signal transmission lines 2a and 2b. and are made entirely of a resistive material. For example, the membrane-type signal transmission lines 2a and 2b, which are divided into two, are formed of a resistor material with a resistance value of about 1 to 10Ω/□, and the resistors 1 and 2 are connected in series.
0 is made of a resistor material having a resistance value of about 50 to 100 Ω/□.

[0015] In an electronic circuit board having a structure in which the film-type signal transmission line 2 including the so-called resistor 10 connected in series is formed of a resistor material as in the above structure, when it is formed of an ordinary conductor. Unlike, the film type signal transmission line 2 can function as a film type signal transmission line 2 with high characteristic impedance without narrowing the width or increasing the length. Furthermore, due to the difference in characteristic impedance and load resistance of the membrane signal transmission line 2, the membrane signal transmission line 2 can also be used as an equivalent reactance element at a specific frequency when L=(2n+1)λg/4. The length L of 2 can also be made shorter than in the case where it is formed of a normal conductor. In other words, it is possible to change the λ length (intraduct wavelength) from the viewpoint of the membrane signal transmission line 2, and it is also possible to easily increase the density. Moreover,
The film-type signal transmission line 2 including the so-called resistor 10 connected in series is manufactured using a so-called thick film process, and by adjusting the resistance paste to an arbitrary sheet resistance and using it, the characteristic impedance can be achieved with the same circuit pattern. functions as different electronic circuit boards.

FIG. 2 is a plan view showing another example of the main structure, that is, the reactance component of the bias circuit. In this example, the main body of the membrane signal transmission line 2 is formed of a normal conductor, and the side chain The reactance component 11, which is arranged in a conventional manner, is formed by a thick film process or a thin film process.

Furthermore, FIGS. 3(a) and 3(b) are plan views showing other examples of the main part configuration. That is, in order to adjust the characteristic impedance of the membrane-type signal transmission line 2, a stub 12 arranged in a side chain manner is formed on the main body of the membrane-type signal transmission line 2 using a resistive paste using a thick film process or a thin film process. It is. In addition, Fig. 3(a)
Figure 3(b) shows the case of an open stub, and Figure 3(b) shows the case of a short stub.

In FIG. 4, curve A schematically shows the resonance situation depending on the λ length when the stub is made of thick film resistor paste, and curve B shows the resonance situation depending on the λ length when the stub is made of a normal conductor. ), the resonance point can be easily adjusted so that it does not become sharp, and the matching band can be widened. Moreover, when the stub 12 is formed of a resistor material, the λ length can be shortened, so that high-density wiring or high-density packaging is possible.

In the present invention, the resistor material constituting at least a part of the film-type transmission line is not limited to those having the above-mentioned resistance values, but is generally referred to as a resistor material of several Ω to Any material having several MΩ can be used.

[0020]

As can be seen from the above description, according to the electronic circuit board according to the present invention, the characteristic impedance of a film-type transmission line for transmitting high frequency signals can be increased. In other words, only the characteristic impedance can be changed without changing the selection and settings of the width and length of the membrane-type transmission line, or the thickness and dielectric constant of the insulating substrate body. Furthermore, since the tube wavelength is shortened and the packaging density can be increased, the degree of freedom in design is improved when configuring a high frequency circuit device.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an example of the configuration of main parts of an electronic circuit board according to the present invention.

FIG. 2 is a plan view showing another example of the configuration of main parts of the electronic circuit board according to the present invention.

FIGS. 3A and 3B are plan views showing still another example of the main part configuration of the electronic circuit board according to the present invention.

FIG. 4 is a curve diagram showing an example of the characteristics of an electronic circuit board according to the present invention in comparison with an example of characteristics of a conventional electronic circuit board.

FIG. 5 is a perspective view showing the main part configuration of a conventional electronic circuit board.

FIG. 6 is a plan view showing the configuration of main parts of a conventional electronic circuit board.

FIG. 7 is a plan view showing the configuration of other main parts of a conventional electronic circuit board.

FIG. 8 is a plan view showing still another main part configuration of a conventional electronic circuit board.

FIG. 9 is a schematic diagram for explaining the relationship between characteristic impedance and reactance with respect to frequency caused by load resistance in an electronic circuit board.

[Explanation of symbols]

1... Insulating substrate main body 2, 2a, 2b... Membrane type transmission line with microstrip line structure 3...
Grounding conductor layer 4... Chip resistance 5... Film resistor 6... Film reactance 7... Bare chip 8... Pad 9... Lead wire
10...Resistor 11...Reactance component
12...Stub

Claims (1)

[Claims] 1. An electronic circuit board comprising an insulating substrate body and a signal transmission line provided on a main surface of the insulating substrate body, wherein at least a part of the signal transmission line is formed of a resistive material. An electronic circuit board characterized by: