JP2002261430A - Wiring pattern for matching - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the capacitance portion of a pad formed on an interconnection. SOLUTION: In the wiring pattern for matching, the pad 36 to which a chip component 8 is attached in a part is formed in the interconnection 35 on a wiring board 34, a deficient part 50 is formed in the pad 36, the area of the chip component 8 and that of the pad 36 are reduced, and the capacitance portion generated in the pad 36 is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a matching wiring pattern capable of reducing a capacitance component of a wiring.

[0002]

2. Description of the Related Art In a current CATV amplifier module, the smaller the wiring capacitance of the feedback circuit, the better. If it is large, the input / output return loss on the high frequency side is greatly deviated from 75Ω.

FIG. 5 is a block diagram of a general CATV amplifier module. An input transformer 2 is connected to an input terminal 1, and an upper front-stage amplifier circuit 3a and a lower front-stage amplifier circuit 3b are connected to the input transformer 2. An upper rear-stage amplifier 4a is connected to the upper front-stage amplifier 3a, and a lower rear-stage amplifier 4a is connected to the lower front-stage amplifier 3b.
b is connected. Further, the output sides of the upper rear-stage amplifier circuit 4a and the lower rear-stage amplifier circuit 4b are connected to an output terminal 6 via an output transformer 5.

Each of the amplifying circuits includes a MESFET, a resistor, a capacitor, and the like. For example, the lower preamplifier circuit 3b includes a MESFET 7, a resistor 8, a resistor 9, a resistor 10, and a capacitor 11. The MES
The gate electrode of the FET 7 is connected to the input transformer 2, and the resistors 8 and 9 and the capacitor 11 are MESFETs.
7 is connected between the gate and drain to form a feedback circuit.

In the CATV amplifier, a wiring pattern is formed on a ceramic wiring board, and a MESF
A hybrid module system in which chip components such as an ET and a resistor and a capacitor are mounted and soldered is adopted.

FIG. 6 is a wiring pattern diagram in which a wiring pattern is formed on the ceramic wiring substrate 14 in the lower preamplifier circuit 3b. A part of the wiring 15 formed on the ceramic wiring board 14 is expanded to form a pad 16, and a tip of the wiring 17 is expanded to form a pad 18. The pad 16 and the pad 18 are provided with the resistor 8 which is a chip component. The electrode portion is placed and soldered.

Similarly, a pad 19 is formed by expanding an end of the wiring 17 different from the above, and a pad 21 and a pad 22 are formed at an end of the wiring 20. The electrode portion of the resistor 9 as a chip component is placed on the pad 19 and the pad 21 and soldered.

The electrodes of the capacitor 11, which is a chip component, are placed and soldered on the pads 22 and the pads 24 on which a part of the wiring 23 formed on the ceramic wiring board 14 is expanded.

The pad 25 has a chip-shaped M
The ESFET 7 is attached, and an electrode portion of the resistor 10 formed on the ceramic wiring board 14 is joined to a pad 27 and a pad 28 in which a part of a wiring 26 formed on the ceramic wiring board 14 is expanded.

FIG. 7 is an enlarged plan view of the pad 16 and the pad 18. The pad is expanded in accordance with the electrode of the chip component to form a rectangle, and the other pads are also rectangular. The wiring is connected as necessary. The ceramic wiring board 14 is provided with a terminal (not shown) for adding or taking out each signal, a power supply terminal (not shown), and is mounted on a radiator.

[0011]

Chip components such as resistors and capacitors, which are circuit elements constituting a circuit such as the CATV amplifier module, are placed on pads formed on wiring and soldered. Since the pad expands in a rectangular shape in accordance with the electrode of the chip component, as the signal to be processed, such as a CATV amplifier, becomes higher in frequency, the pad portion has a capacitive component as the frequency increases, and the characteristic deterioration that did not appear at low frequency Etc. may be adversely affected.

[0012]

According to the present invention, a pad for mounting a chip component is formed on a part of a wiring of a wiring board, a defective portion is provided in the pad, a contact area of the pad is reduced, and a capacitance generated in the pad is reduced. Provided is a matching wiring pattern with reduced components.

[0013] Further, the present invention provides a matching wiring pattern in which a recess is formed in the pad to form a missing portion, or a matching doping pattern in which the pad is formed in a donut shape with the inside being a missing portion. It is another object of the present invention to provide a matching wiring pattern in which a plurality of defective portions of the pad are formed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A matching wiring pattern according to the present invention will be described with reference to FIGS. Note that the same components as those in the related art are denoted by the same reference numerals.

FIG. 5 is a block diagram showing one embodiment of the CATV amplifier module. As described above, the primary winding of the input transformer 2 is connected to the input terminal 1, and the upper preamplifier circuit 3 a and the lower preamplifier circuit 3 b are connected to the secondary winding of the input transformer 2. . An upper rear amplifier circuit 4a is connected to the upper front amplifier circuit 3a, and a lower rear amplifier circuit 4b is connected to the lower front amplifier circuit 3b. Further, the output sides of the upper rear-stage amplifier circuit 4a and the lower rear-stage amplifier circuit 4b are connected to an output terminal 6 via an output transformer 5.

Each of the amplifying circuits includes a MESFET, a resistor, a capacitor, and the like. For example, the lower preamplifier circuit 3b includes a MESFET 7, a resistor 8, a resistor 9, a resistor 10, and a capacitor 11. The MES
The gate electrode of the FET 7 is connected to the input transformer 2, and the resistors 8 and 9 and the capacitor 11 are MESFETs.
7 is connected between the gate and drain to form a feedback circuit.

The CATV amplifier module employs a hybrid module system in which a wiring pattern is formed on a ceramic wiring substrate, and MESFETs and chip components such as resistors and capacitors are mounted on the wiring pattern and soldered.

FIG. 1 is a wiring pattern diagram in which a wiring pattern is formed on the ceramic wiring board 34 in the lower preamplifier circuit 3b. A part of the wiring 35 formed on the ceramic substrate 34 is swelled in a rectangular shape according to the electrode of the chip component to form a pad 36, and the tip of the wiring 37 is swelled in a rectangular shape to form a pad 38. The electrode portion of the resistor 8 as a chip component is placed on the pad 36 and the pad 38 and soldered.

Similarly, a pad 39 is formed by swelling a different end of the wiring 37 into a rectangular shape.
Pads 41 and pads 42 are formed at the ends of the.
The electrode portions of the resistor 9 as a chip component are placed on the pads 39 and 41 and soldered.

The electrodes of the capacitor 11, which is a chip component, are placed and soldered on the pad 44, which is a part of the pad 42 and the wiring 43 formed on the ceramic wiring board 34, which are expanded in a rectangular shape.

The pad 45 has a chip-shaped M
The ESFET 7 is mounted, and an electrode portion of the resistor 10 formed on the ceramic wiring board 34 is joined to a pad 47 and a pad 48 in which a part of a wiring 46 formed on the ceramic wiring board 34 is expanded in a rectangular shape. I have.

FIG. 2 is an enlarged plan view of the pad 36 and the pad 38. The pad 36 and the pad 38 are rectangular as described above. Defective portions 50 and 51 are formed by recessing portions of the pads 36 and 38 where the electrodes of the resistor 8 as chip components are placed.

The resistance 8 of the pad 36 and the pad 38
By forming a deficient portion 50 and a deficient portion 51 by depressing in a portion where the electrode is placed, the area of the pad 36 and the pad 38 is reduced, and the pad 36 and the pad 38 are reduced.
Has been reduced.

FIG. 3 shows another embodiment of the matching pattern of the present invention. By forming a plurality of defective portions 52, 53 and defective portions 54, 55 by recessing a plurality of portions of the pad 36 and the pad 38 where the electrode of the resistor 8 is placed, the pad 36, the electrode, the pad 38 Is reduced, and the capacitance components of the pad 36 and the pad 38 are reduced.

FIG. 4 also shows an embodiment of the matching pattern of the present invention. The missing portions 56 and 57 are formed by hollowing out the insides of the pads 36 and 38, and the pads 36 and 38 are formed in a donut shape.
By forming the pad 36 and the pad 38 in a donut shape, the contact area between the pad 36 and the pad 38 is reduced, and the capacitance component between the pad 36 and the pad 38 is reduced as described above.

Pads 39, 41, 42 and 4 other than the pads 36 and 38
Similarly, the pads 4 and the like have a rectangular shape, and similarly to the pads 36 and the pads 38, the deficient portions are formed by, for example, recessing the portions where the electrodes of the chip components are mounted.

The wires are connected as necessary. The ceramic wiring board 34 is provided with terminals (not shown) for adding or taking out signals, a power supply terminal (not shown), and is mounted on a radiator.

[0028]

According to the wiring pattern for matching of the present invention, a pad for attaching a chip component is formed in a part of the wiring of the wiring board, a defective portion is provided in the pad, the area of the pad is reduced, and the capacitance generated in the pad is reduced. Ingredients can be reduced. Therefore, the wiring capacitance on the high frequency side of the feedback circuit portion such as the CATV amplifier module is reduced, the deviation of the input / output return loss on the high frequency side can be reduced, and the characteristic deterioration in the high frequency band can be suppressed.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of a matching wiring pattern of the present invention.

FIG. 2 is a partially enlarged plan view showing an embodiment of a matching wiring pattern of the present invention.

FIG. 3 is another enlarged plan view showing a part of the embodiment of the matching wiring pattern of the present invention.

FIG. 4 is another partially enlarged plan view showing an embodiment of the matching wiring pattern of the present invention.

FIG. 5 is a block diagram of a CATV amplifier module used to explain the present invention and a conventional wiring pattern for matching.

FIG. 6 is a plan view showing an example of a conventional matching wiring pattern.

FIG. 7 is a partially enlarged plan view showing an embodiment of a conventional matching wiring pattern.

[Explanation of symbols]

 Reference Signs List 8 resistance 9 resistance 10 print resistance 11 resistance 34 ceramic wiring board 35 wiring 36 pad 37 wiring 38 pad 50 defective part 51 defective part 52 defective part 53 defective part 54 defective part 55 defective part

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4E351 AA00 BB01 BB29 BB41 DD01 GG06 5E319 AA03 AB06 AC12 BB01 CC22 GG20 5E336 AA04 BB00 BC34 CC33 CC43 CC51 EE01 GG11 5E338 AA00 BB75 CC01 CD33 EE11

Claims (4)

[Claims] 1. A matching wiring pattern, wherein a part of wiring of a wiring board is expanded to form a pad for mounting a chip component, and a defective portion is provided in the pad to reduce a capacitance component generated in the pad. 2. The matching wiring pattern according to claim 1, wherein a recess is formed in the pad to form a defective portion. 3. The matching wiring pattern according to claim 1, wherein a deficient portion is formed in the pad to form a donut. 4. The matching wiring pattern according to claim 1, wherein a plurality of defective portions of said pad are formed.