JP2578779B2 - Method for measuring transistor characteristics - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for measuring transistor characteristics using a strip line type fixing jig.

Conventional technology To measure the high-frequency characteristics (S parameter and noise figure) of a transistor such as a FET, first mount the transistor on a transistor fixing device, and connect a tuning circuit or bias supply circuit to the input / output of the transistor fixing device. Was common. The transistor fixing device, tuning circuit, and bias supply circuit are independent devices, respectively.
These devices were connected to measure the high frequency characteristics of the transistor. In addition, since these devices are mostly of the coaxial line type, the transistor fixing devices are also generally of the coaxial line type.

FIG. 5 shows a part of a conventional coaxial line type transistor fixing device. Reference numeral 1 denotes a transistor, and reference numerals 2 and 3 denote input / output terminals and a ground terminal of the transistor 1, respectively. Reference numeral 4 denotes a central conductor of the coaxial line, and a slit 5 is provided in the central conductor 4. The input / output terminal 2 is inserted into the slit 5 to position the input / output terminal 2. Numeral 6 denotes an outer conductor of the coaxial line. The outer conductor 6 is narrow at a portion where the transistor 1 is mounted, and a shallow groove 7 for fixing the ground terminal 3 is provided at the narrow portion. And the outer conductor 6
By integrating another outer conductor (not shown) having the same shape with the outer conductor 6, the transistor 1 is mounted and fixed in the outer conductor.

FIG. 6 is a block diagram for measuring high-frequency characteristics of a transistor using a conventional coaxial line type transistor fixing device. In FIG. 6, 8 is a coaxial line type transistor fixing device, 9 is a tuning circuit, 10 is a bias supply circuit, and is a connection between the coaxial line type transistor fixing device 8 and the tuning circuit 9;
The connection between the tuning circuit 9 and the bias supply circuit 10 is connected by a coaxial connector. Then, the tuning circuit 9 tunes the input / output matching circuit of the transistor to measure the high frequency characteristics.

Problems to be Solved by the Invention The conventional coaxial line type transistor fixing device as described above and the method for measuring high frequency characteristics of a transistor using the coaxial line type transistor fixing device have the following problems.

First, in the coaxial line type transistor fixing device, in order to reduce the parasitic inductance due to the ground terminal 3 of the transistor 1, the shape of the external conductor 6 is adjusted to the package shape of the transistor 1, and the gap generated between the transistor 1 and the external conductor 6 is reduced. There is a need. Therefore, transistors having different outer conductor shapes are required for transistors having different package shapes, and therefore, there is a disadvantage that a transistor fixing device having a different outer conductor is required for each package. Further, even if the transistors have the same package shape, if the width of the ground terminal 3 is smaller than the width of the groove 7, the position of the transistor 1 cannot be fixed with good reproducibility. There is a drawback that the transistor 1 cannot be mounted on a transistor having a width larger than the width. Furthermore, since the center conductor 4 is not flat but cylindrical, the shape of the center conductor 4 must be partially flat to fix the input / output terminal 2 of the transistor 1 to the center conductor 4. However, for this reason, the structure becomes complicated, for example, by processing the center conductor 4, or the structure becomes complicated, for example, there is a special contrivance in the supporting method for firmly supporting the center conductor 4 in space. was there.

Next, as shown in FIG. 6, in the high-frequency characteristic measuring method using the coaxial line type transistor fixing device 8, a tuning circuit 9 having a coaxial connector as tuning means or bias supply means is used.
And the use of the bias supply circuit 10, the measurement system becomes large, the loss of the measurement system is large, and the measurement accuracy decreases
Since the distance between the tuning circuit 9 and the transistor is large, the frequency characteristic of the tuning becomes narrow and the tuning becomes difficult. For this reason, it takes a long measurement time. In contrast to the circuit, the measurement system is a circuit using a coaxial line, so that the characteristic result of the measurement system does not always coincide with the characteristic result when mounted on an actual circuit.

The present invention has been made in view of the above, and an object of the present invention is to provide a transistor fixing device that can flexibly respond to the shapes of a package and a package terminal of a transistor.

Means for Solving the Problems The present invention relates to a dielectric substrate disposed on a ground conductor plate, a strip line formed on the dielectric substrate, and a terminal ground conductor provided on the ground conductor plate. A shield plate disposed on the dielectric substrate, a dielectric bar attached to the shield plate, and pressing the input / output terminal of the transistor onto the strip line, and fixed to the shield plate, and A ground terminal crimping part for crimping the ground terminal of the transistor onto the terminal ground conductor; a ground terminal positioning component provided on the tip side of the ground terminal of the transistor for positioning the ground terminal; the shielding plate and the shielding plate; A guide pin that is fitted in a pin hole provided in a direction perpendicular to both of the ground conductor plates, and an input / output matching circuit of the transistor is provided on the dielectric substrate. And a transistor characteristic measuring method for measuring the characteristics of the transistor by using a transistor fixing device, wherein the shape of the input / output matching circuit is made the same or almost the same as the mounting circuit of the transistor. is there.

According to the present invention, the transistor can be fixed on a planar dielectric substrate by the above-described configuration, so that not only can the package be flexibly adapted to the package shape, but also a tuning circuit and a bias supply circuit can be formed on the same dielectric substrate. Therefore, the measuring system can be made smaller. Furthermore, by making the tuning circuit the same as the mounting circuit, not only can the characteristics at the time of mounting be evaluated in advance by the measurement system, but also the measurement time can be greatly reduced. Furthermore, the presence of the guide pins accurately positions the ground terminal and the input / output terminal of the transistor to be crimped by the ground terminal crimping portion and the dielectric rod, and improves the reproducibility of the crimping force. The reproducibility as well as the reliability of the measurement results is obtained.
Since the transistor can be fixed only by applying pressure to press the shielding plate against the ground conductor plate, the work of replacing the transistor is quickened, and the time for replacing the transistor can be greatly reduced.

Embodiments FIGS. 1 and 2 show an embodiment of a strip line type transistor fixing device according to the present invention. In FIGS. 1 and 2, reference numeral 11 denotes a ground conductor plate, on which a dielectric substrate 12 is disposed. Reference numeral 13 denotes a terminal ground conductor, which is provided so as to protrude from the ground conductor plate 11, and has a height substantially equal to the thickness of the dielectric substrate 12. On the other hand, a terminal ground conductor 13 provided with a slot 12 is fitted in the slot 14 in the dielectric substrate 12. The transistor 15 is disposed so that the ground terminal 16 of the transistor 15 is overlapped on the terminal ground conductor 13, and 17 is a ground terminal positioning component for positioning the transistor 15. A groove 18 slightly wider than the width of the terminal 16 is provided. The ground terminal positioning component 17 is such that the ground terminal 16 and the input / output terminal 19 of the transistor 15 are located symmetrically with respect to the strip line 20.
Are screwed in such a position that they can be positioned. twenty one
Is a shielding plate, and the height of the shielding plate 21 is reduced by the pedestal 22 in a portion of the shielding plate 21 facing the transistor 15. On this pedestal 22, the ground terminal 16 is connected to the ground terminal conductor.
Ground terminal crimping part 23 for crimping to 13 and input / output terminal 19
A dielectric rod 24 for attaching the wire to the strip line 20 is attached. Reference numeral 25 denotes a guide pin, and the guide pin 25 is formed so as to be engaged with a pin hole 26 provided vertically to the grounding dielectric plate 11 and the shielding plate 21. Therefore, the first
When the transistor 15 is positioned as shown in FIGS. 1A and 1B, a shielding plate 21 shown in FIG. 1C is placed over the transistor 15 and the shielding plate 21 is pressed against the ground conductor plate 11, and the transistor 15 The ground terminal 16 is grounded to the ground conductor plate 11, and the input / output terminal 19 is crimped to the strip line 20 to function as a strip line type transistor fixing device.

In the embodiment shown in FIGS. 1 and 2, even if the package shape of the transistor 15 is slightly changed, the arrangement of the transistor 15 is not disturbed. is there. By changing the length and width of the grounding terminal 16 by changing the length of the grounding terminal positioning part 17 and the groove width of the groove 18 at the tip of the positioning part 17, only the grounding terminal positioning part 17 is replaced. Can respond. Further, since the strip line 20 is flat, a simple structure that does not require any special complicated processing for crimping the input / output terminal 19 of the transistor 15 is sufficient. Further, since the height of the shielding plate 21 is reduced by providing the pedestal 22 in a portion of the shielding plate 21 facing the transistor 15, radiation of an electromagnetic field near the input / output terminal 19 of the transistor 15 is suppressed,
A transistor fixing device having good electric characteristics can be obtained. Furthermore, a guide pin that fits into a pin hole 26 provided in a direction perpendicular to both the shield plate 21 and the ground conductor plate 11.
25, the positional relationship between the shield plate 21 and the ground conductor plate 11 is accurately determined, and the force applied when the shield plate 21 is pressed against the ground conductor plate 11
As a result, the place where the ground terminal 16 and the input / output terminal 19 of the transistor 15 are crimped by the ground terminal crimping part 23 and the dielectric rod 24 is accurately positioned, and the reproducibility of the crimping force is improved. Therefore, reproducibility as well as reliability can be obtained in the measurement results of the transistor characteristics. Also, the presence of the mating hole 26 and the guide pin 25 makes the shielding plate 21
Since the transistor 15 can be fixed only by applying pressure for pressing the transistor 15 to the ground conductor plate 11, the work of replacing the transistor 15 is quickened, and the work for replacing the transistor 15 can be shortened.

FIG. 3 shows another embodiment of the strip line type transistor fixing device according to the present invention, which relates to the structure of a shielding plate. The same portions as those in FIG. 1 (c) are denoted by the same reference numerals. In FIG. 3, 21 is a shielding plate, 22 is a pedestal, 23
Is a ground terminal crimping part, and 24 is a dielectric rod. The dielectric rod 24 is made of an elastic dielectric material having a low relative dielectric constant and a small dielectric loss, for example, an ethylene tetrafluoride resin. The protrusion length of the dielectric rod 24 from the pedestal 22 is adjusted by the screw 27, and the pressure bonding strength of the input / output terminal 19 of the transistor 15 to the strip line 20 can be adjusted.

In the embodiment shown in FIG. 3, the compression of the input / output terminal 19 to the strip line 20 is performed by utilizing the elasticity of the dielectric rod 24 and the compression strength can be freely adjusted by the screw 27. The contact resistance between the wire and the strip line 20 can be extremely reduced, and the reproducibility of crimping can be ensured.

FIG. 4 shows another embodiment of the strip line type transistor fixing device according to the present invention, which relates to the configuration of a tuning circuit and a bias supply circuit, and the same parts as those in FIG. . On the dielectric substrate 12, a bias supply circuit 28 formed by a low-pass filter, a tuning circuit 29 for the transistor 15, and a DC blocking circuit 30 are provided. Reference numeral 14 denotes a slot, into which the terminal grounding conductor 13 enters. Reference numeral 31 denotes a screw hole for fixing the ground terminal positioning component 17 to the ground conductor plate 11 with a screw. Normal,
The width of the slot 14 is selected to be smaller than the size of the package of the transistor 15 and larger than the width of the ground terminal 16. The reason is to prevent the tuning circuit 29 from contacting the terminal ground conductor 13 even when the tuning circuit 29 is provided closest to the transistor 15.

In the embodiment shown in FIG. 4, the tuning circuit 29 is provided close to the transistor 15, so that the tuning frequency characteristic becomes wide. Since the tuning circuit 29 is fixed, the measurement time is reduced. By making the tuning circuit 29 the same shape as the mounted circuit, the characteristics when the transistor is mounted on the mounted circuit can be accurately predicted. In particular, it is effective when a highly accurate measurement such as a noise figure characteristic is required and it is required to accurately predict the characteristic of the mounted circuit. The bias supply circuit 28 is the same dielectric substrate as the tuning circuit 29
Since it is formed on 12, the measurement accuracy can be improved because the measurement system can be made small and the loss can be made small. In addition, the measurement result can be quantitatively extremely close to the characteristic result at the time of mounting on the mounting circuit, and the practical effect is very large.

Effect of the Invention As described above, according to the present invention, the transistor fixing device is of the strip line type, so that there is an effect that the means for fixing the transistor is flexible with respect to the package shape of the transistor. The use of the guide pin can provide not only reliability and reproducibility of the measurement result of the transistor characteristics, but also shorten the time required for replacing the transistor. Furthermore, since a bias supply circuit can be configured together with a tuning circuit on the dielectric substrate of the transistor fixing device, the measurement system can be reduced, the measurement time can be significantly reduced, and practical characteristic results can be obtained. The effect is obtained.

[Brief description of the drawings]

1 (a), 1 (b) and 1 (c) are a plan view, a side view and a perspective view of a transistor fixing device according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the transistor fixing device of FIG. FIG. 3 is a partial cross-sectional view of a shielding plate of a transistor fixing device according to another embodiment of the present invention. FIG. 4 is a structural view of a dielectric substrate of the transistor fixing device according to another embodiment of the present invention. FIGS. 1A and 1B are a plan view of a conventional coaxial line type transistor fixing device and FIG.
FIG. 6 is a block diagram of a high frequency characteristic measurement of a transistor using a conventional coaxial line type transistor fixing device. 11: Ground conductor plate, 12: Dielectric substrate, 13: Terminal ground conductor, 14: Slot hole, 15: Transistor, 16: Ground terminal, 17: Ground terminal positioning component, 18: Groove , 19 ... I / O line, 20 ... Strip line, 21 ... Shield plate, 22
… Pedestal, 23… ground terminal crimping part, 24… dielectric rod, 25
... Guide pin, 26 ... Pin hole, 27 ... Screw, 28 ... Bias supply circuit, 29 ... Tuning circuit, 30 ... DC blocking circuit, 31 ... Screw hole.

Claims (4)

(57) [Claims] A dielectric substrate disposed on a ground conductor plate;
A strip line formed on the dielectric substrate, a terminal ground conductor provided on the ground conductor plate, a shielding plate disposed on the dielectric substrate, a transistor attached to the shielding plate, and a transistor A dielectric rod for crimping the input / output terminal of the transistor on the strip line, a ground terminal crimping part fixed to the shielding plate, and crimping a ground terminal of the transistor on the terminal ground conductor; A ground terminal positioning component that is provided on the tip side of the ground terminal and positions the ground terminal; and a guide pin that fits into a pin hole provided in a direction perpendicular to both the shield plate and the ground conductor plate. The input / output matching circuit of the transistor is provided on the dielectric substrate, and the shape of the input / output matching circuit is the same as that of the mounting circuit of the transistor. Or using transistors fixing device being characterized in that substantially the same shape, the measurement method of a transistor characteristic measuring characteristics of said transistor. 2. The method according to claim 1, wherein the length of protrusion of the dielectric rod attached to the shielding plate from the shielding plate can be changed by a screw provided on the shielding plate, and the dielectric rod is made of an elastic material. The method for measuring transistor characteristics according to claim 1, characterized in that: 3. The transistor characteristic according to claim 1, wherein a metal conductor is used for the ground terminal crimping portion, and a height of the shielding plate is set low at a portion facing the transistor. Measuring method. 4. The method according to claim 1, wherein the transistor bias voltage supply circuit is formed by a strip line on a dielectric substrate.