JPS5816587A - Circuit device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a circuit device in which the dimensions of a ground pattern provided on an insulating substrate are such that resonance does not occur within the frequency band used by the loudspeaker circuit device.

In a circuit device as shown in FIG. 1, a microwave circuit 2 is mounted on an insulating substrate 1, and an active element 3 or a capacitive passive element 4, etc. is placed on the insulating substrate 1 in parallel with the microwave circuit 2. In this case, a ground pattern 6 connected to the ground 5 at both ends of the insulating substrate 1 is stretched in a band shape, and the active element 3 or the passive element 4 is mounted on the upper surface of the ground pattern 6. . Incidentally, FIG. 2 also shows a similar circuit device, but in this figure, the earth pattern 6'
Extends from ground 5 at both ends to near the center, and closes the ends with open ends.

As shown in FIG. 3, such a circuit device is installed on a metal casing T for various communication and electronic devices, but at this time, the ground pattern 6, 6' is connected to the ground 5 at the end. It is grounded to the chassis TK via.

However, in this case, K as is clear from Figure 3.

The ground patterns 6° and 6' should be floating from the casing T by the thickness of the insulating substrate 1. In the ultra-high frequency band used by the circuit device, the capacitance between the ground patterns g and 6' and the casing T is small. The first effect was on the conductivity, and the effect on the casting property.
In the case where both ends are connected to ground 5 as shown in the figure, a stub-like KlkD with both ends shorted, or a second
In the case where one end is connected to the ground SK and the other end is open, as shown in the figure, there is no open stub shape, and depending on the relationship between the operating frequency of the circuit device and the dimensions of the ground pattern 6.6', resonance may occur in the circuit. Cracks sometimes appeared in the band characteristics of the frequency used by the device.

The present invention has been made in response to the above-mentioned circumstances, and provides a circuit device in which the dimensions of the ground pattern provided on the insulating substrate are such that resonance does not occur within the frequency band used by the circuit device. The purpose is to provide.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 1, the circuit device according to the present invention has a microwave circuit 2, etc. mounted on the upper surface of an insulating substrate 1 made of sapphire or the like, and its flesh @11! Housing for mKld communication, electronic equipment, etc.?
(See Figure 93) A grounding ground 5 is provided on the upper surface of the insulating substrate 1, and a band-shaped grounding pattern 6 is provided in a cypress-shaped manner, with both ends electrically connected to the grounding 5.
The active element 3 or the passive element 4 is mounted on the upper surface of this grounding element 76.

Here, the dimensions of the ground pattern 60, that is, the length between both ends connected to the ground 5.5, are determined as follows. Now, in Figure 114, the length of the earth pattern 6 to be sought is the length from one end to the origin of the coordinates and the other end, and this is X; The low frequency of the band used by the circuit device is also faxed, and its wavelength is λa; Let fbs be the highest frequency in the band used by the circuit device and its wavelength λb. and ζ
Generally, in the ultra-high frequency band, between the length X of the ground pattern 6 and the point Q of the current frequency, the wavelengths of the band frequencies fa and fb are always 100 wavelengths. Also, λb
Between the point R of and the point S of λa, the band frequency fa = f
The wavelengths of b are always the same. Therefore, earth pattern 6
When the other end is in the relationship between P and Q% and S%T and U, the length The Rukoto.

Therefore, the length K should be such that the other end of the ground pattern 6 does not fall within the above range. In other words, if it is within the range of 0 and P%Q and L 8 and T, the length of the earth pattern @
is never equal to the band frequency Σ or an integer multiple thereof. This can be expressed numerically as follows.

0 (x (-λb, -λa < X <-λb% ”
λa<X<-λb...22 22
2 Generalizing these equations, we get: ζ - λ wet < X < T λb for Kawamachi (1) 0 (x. However, n is a natural number.

Here, if the speed of light is 01 and the wavelength shortening rate of the earth pattern 6 provided on the insulating substrate 1 is r, then the electrical speed on the insulating substrate 1 is rC. Therefore, the frequency fa or fb
The wavelength λa or λb when
, (1) and (2), X is expressed as follows.

Mr. 029 nrc 2a <x勺、-・・・・・・・・・ (3) This (3
) is the formula for determining the length X of the earth pattern 6.

Therefore, the dimensions of the ground pattern 60 can be determined so as to satisfy the above equation (3), and resonance in the ultra-high frequency band of the nine-wave circuit device can be prevented from occurring.

FIG. 2 is a perspective view showing a circuit device having a ground pattern 6' having one end connected to the ground 5 at both ends of the insulating substrate 10, the other end extending to the vicinity of the center, and the other end being an open end. The dimensions of the ground pattern 6' in this case, that is, the length between one end connected to the ground 5 and the other open end, are determined as follows.

Now, in Fig. 5, the length of the earth pattern 6' to be sought is defined as the length from one end to the coordinate origin AK, and this is y; the lowest frequency of the band used by the circuit device is f.
Assume that ax its wavelength is λa; the highest frequency of the band used by the circuit device 'tftth and its wavelength is λb. and ζro,
In the ultra-high frequency band, in the earth pattern 6' with the other end open as described above, the wavelength of the band frequency fa-fb is always the i wavelength between waves whose length y is the roaring scissor frequency. Hereinafter, in the same way as in the case of FIG. 4, the number of wavelengths is i.times.5. Therefore, when the other end of the ground pattern 6' is in the relationship between B, C%D, E%F and q, the length y of the ground pattern 6' will be i wavelength of the band frequency or an odd multiple thereof, Resonance will occur.

At that ζ, the other end of the ground pattern 6' is within the above range λ
You can make it as long as you want. That is, A and B%C
Within the range of D%E and F, the length y of the earth pattern 6' will never be equal to the band frequency i or an odd multiple thereof.This can be expressed mathematically as 1. In the same way as in the case of FIG. 4, the following results are obtained.

°　.

7-λhata <ykuko λb ・・・・・・・・・(4) n-
3 0<y By substituting the above equation (2) into this equation (4), 0<y is obtained. This equation (5) is the equation that determines the length y of the earth pattern 6'. Therefore, if the dimensions of the ground pattern 6' are determined to satisfy the above equation (5), it is possible to prevent resonance in the ultra-high frequency band of the circuit device.

Since the present invention is configured as described above, by determining the dimensions of the ground pattern 6 or 6' to satisfy the above formula (3) or (4), it is possible to It is possible to prevent resonance from occurring. Therefore, cracks can be prevented from occurring in the frequency band characteristics used by the circuit device, and the characteristics can be improved.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a circuit arrangement having an earth pattern connected to earth at both ends, jll! Figure 2 is a perspective view showing a circuit device having a ground pattern with one end connected to ground and the other end open, Figure 3 is a sectional view of the main part of the circuit device, and Figures 4 and 5 are circuits! ! FIG. 3 is a diagram illustrating the relationship between the wavelength of the frequency of the frequency band used by the equipment and the length of the earth pattern. 1...Insulating board 5...Ground 6.6'...Earth pattern f,...Lowest frequency fb...Highest frequency λa...Wavelength of the lowest frequency λb...
・Wavelength of the highest frequency Relationship with person 1'1 who filed application No. 174 3hlil Last applicant's address 1015 Kamiodanaka, Nakahara-ku, Yozaki Φ, Kanagawa Prefecture (522) f+
p+, Fujitsu Limited, 8th Supplement 11, 6'A, as per the paper L. The scope of claims described in the specification, page 1, line 4 to page 2, line 7, is amended as follows〇[ (1) In a circuit device that has a band-shaped ground pattern on an insulating substrate, and both ends or one end of this ground pattern are connected to the ground at the side edges of the board, the ground pattern is connected to the ground at both ends. The dimensions are within a range shorter than n times the wavelength i on the highest frequency circuit device and longer than (n-1) times the wavelength i on the lowest frequency circuit device in the band used by the circuit device. A circuit device characterized by:

Claims (1)

[Scope of Claims] (1) In a circuit device that has a band-shaped ground pattern (turn) on an insulating substrate, and both ends or one end of this ground pattern are connected to the ground Kll at the side ends of the board, both ends are connected to the ground Kll. A circuit device whose dimensions are the same as the wavelength of the highest frequency circuit device in the band used by the circuit device. Q) One end is connected to the ground and the other end is The dimensions of the open ground pattern are set to be shorter than the power of the circuit device and at the wavelength of the lowest frequency. The circuit device according to claim 1, characterized in that the circuit device is bound within a range longer than (n-1) times. (3) Dimensions of a ground pattern with one end connected to ground and the other end open.
2. The circuit device according to claim 1, wherein the circuit device is within lll1 which is 0 times longer and 2n-3 times longer.