JPH0110957Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high frequency device, and particularly to a high frequency device including a plurality of circuits.

Conventionally, when configuring a high-frequency device such as a high-frequency amplifier, multiple circuits such as a high-frequency circuit and a bias circuit are configured on separate printed circuit boards in separate rooms separated by a side wall of the case, and the circuits are biased via a feed-through capacitor or feed-through filter. Bias was supplied from the circuit to the high frequency amplifier circuit. In this case, the feedthrough capacitor or feedthrough filter serves as a bypass capacitor or a low-pass filter to remove high frequency components. FIG. 1 is a mounting diagram showing the inside of a conventional high-frequency device, which includes a high-frequency circuit 1, a bias circuit 2, a bias circuit board 3, a feedthrough capacitor 4, a feedthrough capacitor 5 for DC power supply, an input/output connector 6, Each individual printed circuit board 3
, which are individually screwed to the case.

However, in ultra-high frequency bands such as microwave bands, the size of the room for the high-frequency amplifier circuit is limited depending on the frequency in order to prevent resonance due to waveguide mode and the like. As a result, as the frequency increases, for example over 10 GHz, the size of the room becomes smaller and the distance between the screws used to fix the printed circuit board to the case and the printed pattern of the high frequency circuit becomes shorter, causing parasitic resonance. However, there was a drawback that screws could not be installed at locations where fixation was required. That is, as the frequency increases, it is no longer possible to use the conventional method of creating each circuit on a separate printed circuit board and combining them.

Therefore, the purpose of the present invention is to configure individual circuits such as a high frequency circuit and a bias circuit on the same substrate, and to create a special shielding structure between each circuit so that it can be applied to high frequencies. An object of the present invention is to provide a new high frequency device.

According to the present invention, when individual circuits such as high frequency circuits and bias circuits are formed on the same printed circuit board with a ground pattern on the back side, and conductive side walls surrounding each circuit are provided, the side walls between the circuits are A high frequency device is obtained in which a radio wave absorber is interposed between the printed circuit board and at least one of the other side walls is in contact with a through hole communicating with a grounding pattern provided on the printed circuit board.

In the present invention, it is sufficient to use one printed circuit board for a plurality of circuits, eliminating the need for conventional assembly and simplifying the work. Furthermore, by using a radio wave absorber, the conventionally used feedthrough capacitor and feedthrough filter can be omitted, and therefore connection work is also unnecessary. Furthermore, since the side wall is connected to the ground pattern via the through hole, parasitic resonance of the high frequency circuit can also be prevented.

Next, the present invention will be described in detail with reference to the drawings of an embodiment of the present invention.

FIG. 2 is a mounting diagram of an embodiment of the device of the present invention, which is equipped with a high frequency circuit 1 and a bias circuit 2, and a connecting line 7 between the two circuits is configured on the same printed circuit board 8. The high frequency circuit 1 portion of the printed circuit board 8 is sandwiched between side walls 9 and 10 in a case 12. In the present invention, in order to perform the same function without using a feedthrough capacitor or a feedthrough filter, a radio wave absorber 11 is sandwiched between the sidewall 9 and the printed circuit board 8 to remove high frequency components. The portion of the printed circuit board that is in contact with the bottom surface is a ground pattern that is electrically connected to the back surface of the printed circuit board, the entire surface of which is a ground pattern, through a through hole in order to bring the side wall to a ground potential.

FIG. 3 is an exploded view of the vicinity of the high-frequency circuit in FIG.
4 is shown.

FIG. 4 is a diagram showing another embodiment of the present invention,
If each side wall is connected to form an integral structure as shown in the figure,
This has the advantage of reducing the number of parts and reducing assembly time. Here, 15 represents a side wall having an integral structure.

In the above description, an example has been described in which there is one high frequency circuit and one bias circuit, but it goes without saying that the present invention can also be applied to a device having two or more of these high frequency circuits and two or more bias circuits. FIG. 5 shows an embodiment of the present invention in which there are four circuits. In this case, the connection line between the high-frequency circuits is also constructed on the same printed circuit board as the circuit, and the bottom part of the side wall through which the connection line between the high-frequency circuits passes is provided with a notch so that the high-frequency radio waves are not attenuated. An insulating radio wave absorber as shown in the embodiment shown in Fig. 3 is sandwiched between the side wall portion where the connecting line between the high frequency circuit and the bias circuit passes, to prevent the grounding wire from coming into contact with the side wall. Preventing.

Figure 6 shows the side wall 1 of the equipment shown in Figure 5 to completely shield the equipment and improve reliability.
5 is further covered with an outer wall 16 according to an embodiment of the present invention.

As explained above, the present invention configures multiple circuits in a high-frequency device on the same printed circuit board,
The printed circuit board is structured so that the printed circuit board can be attached to the case using the side wall that separates each circuit, a radio wave absorber is sandwiched between the side wall between the circuits and the printed circuit board, and a through hole is formed in the part of the printed circuit board that touches the bottom of at least one side wall. By adopting a structure in which the ground pattern is formed through the ground pattern, it is possible to easily attach the printed circuit board to the case, reduce the number of parts, and prevent parasitic resonance of the high frequency circuit.

[Brief explanation of the drawing]

Fig. 1 is an implementation diagram of a conventional high frequency device, Fig. 2 is an implementation diagram of the first embodiment of the present invention, Fig. 3 is an exploded view of the vicinity of the high frequency circuit in Fig. 2, and Fig. 4 is an implementation diagram of the first embodiment of the present invention. FIG. 5 is a diagram showing another embodiment of the present invention in which the side walls of FIG. The figure which shows the example when further implementing in one case. In the figure, 1... High frequency circuit, 2... Bias circuit, 3... Bias circuit board, 4... Feedthrough capacitor, 5... Feedthrough capacitor, 6... Input/output connector, 7... Bias supply line, 8 ... Printed circuit board, 9, 10 ... Side wall, 11 ... Radio wave absorber, 12 ... Case, 13 ... Ground pattern,
14...Screw, 15...Connected side wall, 16...
outer wall.

Claims (1)

[Scope of utility model registration request] A high-frequency device that includes at least a high-frequency circuit, a bias circuit that generates a bias to be supplied to the high-frequency circuit, and a connection circuit between these two circuits, and that shields these two circuits from each other, wherein the high-frequency circuit and the bias circuit are connected to each other. When the two circuits are configured on a single printed circuit board with a ground pattern on the back side, and the two circuits are surrounded by conductive side walls,
An insulating radio wave absorber is interposed between the side wall between the two circuits and the printed circuit board,
A high frequency device characterized in that at least one of the other side walls is in contact with a through hole that communicates with the ground pattern on the back surface of the printed circuit board at a position where this side wall is installed.