JPH0440001A - Microwave 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] <Industrial Application Field> The present invention relates to a microwave device including a frequency filter circuit, and in particular to realizing miniaturization and high reliability of a microwave device using MMIC. be.

<Prior art> As a conventional example of a microwave circuit including signal processing circuits such as signal amplification, frequency conversion (mixing), and filtering, an example of the configuration of a front end section (down converter) of a microwave receiver is shown in Fig. 3. . Here, 30 is a microwave signal input terminal, 31 is a low noise amplifier, 32 is a bandpass filter circuit or image band removal filter circuit, 33 is a mixer, 34 is a local oscillator, 35 is an intermediate frequency amplifier, and 36 is an intermediate frequency amplifier. This is a frequency output terminal. The received signal is amplified by a low-noise amplifier 31, and then input to a mixer 33, where it is mixed with a local oscillation signal and converted to an intermediate frequency. At this time, the filter circuit 32 attenuates the image frequency that becomes a problem during mixing. Conventionally, the circuit shown in FIG.
It was formed of a C (Micr□wave IC) circuit. Furthermore, a half-wavelength side coupling filter using a microstrip line is often used in the filter circuit.

On the other hand, in recent years, the electronic mobility of GaAs threads and InP-based materials is 5 to 6 times higher than that of Si, so the development of field effect transistors and modulation doped field effect transistors using these materials has progressed. Furthermore, attempts are being made in various places to monolithically integrate these transistors, matching circuits, bias circuits, and the like. This monolithic IC is MMIC (Monolithic Micro
It is called a wave IC) and has the characteristics of being smaller and more reliable than conventional MIC circuits. For this reason, S
MMICs for different functional blocks such as low-noise amplifiers and mixers for HF band direct satellite broadcast reception have been reported.

<Problems to be Solved by the Invention> However, there are very few proposals for converting a filter circuit into an MMIC. This is because configuring the filter circuit using MMIC requires a large area. For example, when attempting to convert the front end section into an MMIC, the fill circuit 32 becomes large, so this section cannot be configured as a single MMIC, and the low noise amplifier 31 and mixer 33 before and after the fill circuit 32 become large. Intermediate frequency amplifier 35
MM
The miniaturization and high reliability of ICs are being hindered.

In view of the above, it is an object of the present invention to downsize and increase the reliability of a microwave circuit section having a frequency filter circuit therebetween, and to downsize and increase the reliability of a microwave device including such a circuit configuration. .

<Means for Solving the Problems> Therefore, the present invention combines circuits before and after the frequency filter circuit into one.
The present invention is characterized in that the frequency filter circuit is a separately formed circuit.

According to the present invention, a frequency filter circuit that is difficult to form on a semiconductor substrate is formed using a microstrip line or the like on a dielectric substrate, and the circuits before and after the circuit are formed as a frequency filter circuit. Since MMIC can be formed on a semiconductor substrate without being affected, the number of chips can be reduced, and the microwave circuit section having a frequency filter circuit therebetween can be made smaller and more reliable.

<Example> The present invention will be explained below using examples.

An embodiment of the present invention is shown in FIG. In Figure 1, 1
3 is a one-chip MMIC formed on a semiconductor substrate with all functional blocks except the filter circuit 32 in FIG. 3, 2 is an input terminal for microwave signals, 3 is an output terminal from the MMICI to the filter circuit 32, and 4 is input terminal of the filter circuit,
5 is the output terminal of the filter circuit, 6 is the input terminal for the signal from the fill circuit 32 to MMICI, and the other numbers are the same as in FIG. 3. As described above, the present invention is characterized in that the filter circuit and other functional blocks are separated, and both the filter circuit 32 and the MMICI are provided with input/output terminals for receiving and passing signals. . Therefore, the functional blocks other than the fill circuit, which require a large area, can be integrated into one chip on the semiconductor substrate, so the number of chips can be significantly reduced compared to the conventional example. Furthermore, the number of connections between functional blocks is greatly reduced, and in the example of the present invention shown in FIG. 1, there is only a connection between the filter circuit 32 and the MMICI.

As a result of the above, according to the example of the present invention, the receiver can be made smaller and more reliable.

Although a microwave receiver has been taken as an example above, the present invention is not limited thereto, and can be widely applied to microwave devices including a frequency filter circuit.

In addition, although the fill circuit 32 and MMICI are configured on the same plane in FIG. 1, the fill circuit 32 and MMICI do not need to be configured on the same plane.
By forming a frequency filter circuit using strip lines on a multilayered dielectric substrate and mounting an MMIC on this dielectric substrate, the microwave device can be further miniaturized. The schematic configuration diagram in FIG. 2 shows an example in which the filter circuit 32 and MMIC1 are connected and integrated using a multilayer substrate 22.

FIG. 2(a) is a top view, in which the MMICI mounted on the substrate 22 is connected to a transmission line 24 connected to an external circuit by a wire 25, and connected to an intermediate layer 26 by a wire 25 via a via hole 23. Formed fill circuit 32
(omitted in the drawing). Viaho) v2
3 is the output terminal 3. They are provided at two locations corresponding to the input terminals 6. FIG. 2('b) is a cross-sectional view taken along the line AA' in FIG. It is formed.

In the present invention, the number of MMICs does not need to be one; for example, the oscillator in FIG. 1 is a separate chip, and the present invention is effective even in a two-chip configuration.

Further, a plurality of filter circuits may be included.

The substrate forming the MMIC or fill circuit is also not particularly limited.

<Effects of the Invention> As explained above, according to the present invention, a frequency filter circuit that is difficult to make into an MMIC can be connected to the outside of a semiconductor chip, and a circuit that can be easily made into a monolith can be made into an IC on a semiconductor substrate. As a result, the microwave device can be made smaller and more reliable.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of a front end section showing an embodiment of the present invention, Fig. 2 is a schematic diagram of a connection using a multilayer board, and Fig. 3 is a circuit diagram of a front end section of a conventional receiver. It is a diagram. l...MMIC3...Output terminal 4...Input terminal 5...Output terminal 6...Input terminal 22
... Board 23... Viaho/I/26...
Middle class 32...Fill circuit agent Patent attorney Ume 1) @ (2 others) Me Figure 1 Figure 2 Stone Figure 3

Claims (1)

[Claims] 1. The frequency filter circuit includes a circuit configuration in which other types of circuits are connected to the front and rear stages of the frequency filter circuit, the front and rear circuits are one integrated circuit, and the frequency filter circuit is formed separately on the integrated circuit. A microwave device characterized in that it has a connected structure.