JPH071863B2 - Semiconductor switch device - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a high voltage, high current semiconductor switch device which constitutes a part of a pulse generation circuit used in a pulse laser device or the like.

[Prior art]

Figure 9 shows, for example, "Copper Vapor Lasers
Come Of Age (Laser Focus, July Issue, 198
2 years) COPPER VAPOR LASERS COME OF AGE (LASER FOCUS,
JULY, 1982) ”, which is a circuit diagram showing a pulse generation circuit for a conventional copper vapor laser device, in which 1 is a high-voltage DC power supply, 2 is a charging reactor, 3 is a charging diode, Reference numeral 4 is a capacitor for charging and discharging, 5 is a resistor for charging, 6 is a thyratron switch for discharging, and 7 is a laser tube. Next, the operation will be described. High voltage generated from DC power supply 1 (several KV to several tens KV),
The capacitor 4 is charged through the reactor 2, the diode 3 and the resistor 5. Next, thyratron switch 6
When a conduction signal is applied to the grid of the thyratron switch 6 and the thyratron switch 6 becomes conductive, the voltage stored in the capacitor 4 passes through the thyratron switch 6 and the laser tube 7
Is applied as a pulse voltage. At that time, the impedance of the laser tube 7 is significantly smaller than the resistance value of the resistor 5, so that the current flowing through the cylitron switch 6 mainly flows through the laser tube 7. This allows
The laser tube 7 is excited to generate laser oscillation. Generally, in the case of a copper vapor laser device, if a steeper pulse voltage is applied to the laser tube 7, a higher laser output can be obtained. Therefore, the thyratron switch 6 used as a switch is required to switch for several tens of nanoseconds.

[Problems to be Solved by the Invention]

Since the pulse generation circuit used in the conventional copper vapor laser device or the like is configured as described above, the laser tube 7
The thyratron switch 6 for high power, which can be switched on in a few tens of nanoseconds, is used as a switch used in the pulse generation circuit in order to make the pulse voltage supplied to the device steeper and to increase the laser efficiency. Since the thyron switch 6 is a vacuum tube, it has a finite life and needs to be replaced frequently, and the thyratron switch 6 is a handmade product. However, there were problems such as deterioration of quality stability and reliability. The present invention has been made to solve the above problems, and provides a semiconductor switch device suitable for use in a pulse generation circuit, which has a semi-permanent life and can improve stability and reliability. The purpose is to get.

[Means for Solving the Problems]

In the semiconductor switch device according to the present invention, a plurality of semiconductor switches connected in series and parallel to each other are arranged in a first cylinder, and one end of a series circuit of each semiconductor switch is connected to the inside of the first cylinder. It is connected to a second cylindrical body made of a conductor provided outside, and two support rings are fitted into one end of the first cylindrical body, and a plurality of capacitors are connected in parallel between them, and The other end of the above-mentioned series circuit is connected to the support ring.

[Action]

In the semiconductor switch device according to the present invention, the second cylindrical body makes it possible to obtain an even current distribution and also to obtain an integrated pulse generation circuit including a capacitor for obtaining a pulse voltage in a compact form. .

【Example】

An embodiment of the present invention will be described below with reference to the drawings. First
3 to 3 show the first embodiment of the present invention, the portions corresponding to those of FIG. In FIG. 3, reference numeral 8 is a plurality of semiconductor switches, and FET (field effect transistor) 8 is used in this embodiment. In these FETs 8, a plurality of series circuits in which the drain terminals D and the source terminals S of the n FETs 8 are connected to each other are connected in parallel between the connection point of the diode 3 and the capacitor 4 and the DC power supply 1. And each FE
A series-parallel circuit is configured by connecting each T8 in parallel. 9 _{I to} 9 _n are conduction signal input terminals, and are commonly connected to the gate terminals G of the FETs 8 in the n parallel circuits of the FETs 8. In FIGS. 1 and 2, 10 is a cylindrical first cylindrical body made of an insulating material, and 11 is a conductor arranged coaxially at a predetermined interval inside the first cylindrical body 10. The second cylinder of the cylindrical body, 12 is a short-circuit ring provided on one end surface of the first and second cylinders 10 and 11, and 13 and 14 are a predetermined distance outside the end of the first cylinder 10. Capacitor support rings consisting of ring-shaped conductors arranged with
It has 13a and 14a. Reference numeral 4a denotes a plurality of capacitors which are connected in parallel to each other by being supported by connecting both ends to the flanges 13a and 14a, and constitute a large-capacity capacitor 4 of FIG. 3 as a whole. Reference numeral 15 is a terminal connected to the support ring 14, and 16 is a terminal connected to the second tubular body 11. The outer peripheral surface of the first cylindrical body 10 has a plurality of
The FETs 8 are connected in series and parallel to each other. N FETs 8 are connected in series along the axial direction of the first cylindrical body 10,
This series circuit is provided in parallel in a plurality of rows, and the drain terminal D of the FET 8 at one end of each series circuit is connected to the support ring 13.
The source terminal S of the FET 8 at the other end is connected to the short-circuit ring 12. The connection point between the drain terminal D and the source terminal S of each FET 8 is connected by a plurality of circumferential lead wires 17. Next, the operation will be described. In order to improve the stability of the switch and shorten the life of the switch, a FET 8 as a semiconductor switch is used in this embodiment in place of the conventional vacuum tube thyratron switch 6. However, a single semiconductor switch capable of switching several KV to several tens of KV and several tens of nanoseconds as realized by the thyratron switch 6 cannot exist at present. FETs as semiconductor switches that realize switching of several tens of nanoseconds have a maximum withstand voltage of only about 1 KV, so
In order to obtain a withstand voltage of several KV to several tens of KV, as shown in Fig. 3,
Multiple series connection of high-speed semiconductors such as FET8 is required. However, when the FETs 8 are connected in series and parallel, it is difficult to evenly distribute the current to each FET 8 especially in parallel connection.
The current distribution during the extremely fast time (several hundreds of nanoseconds) of the copper vapor laser device is determined by the counter electromotive force of the inductance of the circuit determined by the geometrical shape rather than the ON voltage determined by the characteristics of the FET8. In FIG. 1 according to the first embodiment of the present invention, a second cylinder body 11 made of a conductor is coaxially arranged inside a first cylinder body 10 in which a series-connected FET 8 is arranged. The second tubular body 11 forms a current return path. Therefore, each
The inductance seen from the FET 8 is uniform, the current flows evenly, and the switching characteristics of the FET 8 as a whole are improved. The terminal 15 is connected to the connection point between the diode 3 and the capacitor 4 in FIG. 3, and the terminal 16 is connected to each end of the DC power source 1, the laser tube 7 and the resistor 5. FIG. 4 shows a second embodiment, in which a plurality of hook-shaped FET fixing fittings 18 are provided on the outer peripheral surface of the first cylindrical body 10, and the FETs 8 are vertically supported by the respective fixing fittings 18. Is. In this case, the drain terminal D (not shown) of the FET 8 is directly connected to the fixing metal fitting 18, and the connection with the source terminal S of the adjacent FET 8 is made through the fixing metal fitting 18. Further, the connection in the circumferential direction is made via the lead wire 19 and the fixing metal fitting 18. According to the above configuration, since the FET 8 is arranged vertically, the length of the first and second cylindrical bodies 10 and 11 can be made shorter than that of FIG. In the first and second embodiments, the first tubular body 10 and the second tubular body 11 are coaxially arranged at a predetermined interval, and both are connected by the short-circuit ring 12. As shown in FIG. 5 showing the third embodiment, the source terminal S of the FET 8 is directly connected to the second cylindrical body 11
And the short-circuit ring 12 may be omitted. Further, in the first to third embodiments, the first and second cylindrical bodies 10,1
Although 1 has a cylindrical shape, square first and second cylindrical bodies 10 and 11 may be used as shown in FIG. 6 showing the fourth embodiment. 7 and 8 show a fifth embodiment, in which the first cylinder 10 is arranged inside the second cylinder 11. The first cylindrical body 10 is composed of a plurality of conductors.
Mounting ring 10a for FET mounting and these mounting rings 10a
Insulator ring that connects together to form a tubular body
It is composed of 10b and. A heat radiating portion 10c is integrally provided inside the mounting ring 10a.
The FET 8 is attached with its drain terminal D connected. In addition, at one end of the first cylindrical body 10, support rings 13, 14 are provided.
Are provided so as to project outward from the second cylindrical body 11, and a plurality of capacitors 4a are provided between the flanges 13a and 14a.
Is provided. The n FETs 8 are connected in series along the axial direction of the first cylindrical body 10, and the series circuits are arranged in parallel in a plurality of rows (four rows in FIG. 8).
The drain terminal D of the FET 8 at one end of each series circuit is connected to the support ring 13 via the heat radiating portion 10c, and the source terminal S of the FET 8 at the other end of each series circuit is connected to the short-circuit ring 12. Further, as shown in FIG. 8, the connection point a between the heat dissipation portion 10c to which the drain terminal D of each FET 8 is connected and the source terminal S is connected by a plurality of circumferential lead wires 17, so that n Parallel circuit is configured. According to the fifth embodiment, the second cylindrical body 11 that is a conductor is used.
As a result, since the periphery of the first cylindrical body 10 is covered, a shielding effect such as preventing noise and the like from leaking to the outside can be obtained. Also in the fifth embodiment, the source terminal S of the FET 8 may be directly connected to the second tubular body 11 to omit the short-circuit ring 12, and the first and second tubular bodies 10, 11 may be omitted. May have a rectangular shape. Further, although the FET 8 is used as the semiconductor switch in the first to fifth embodiments, SIT, IGBT, SI thyristor, transistor, thyristor or the like may be used. Furthermore, the present invention is not limited to copper vapor laser devices and the like, but can be applied to semiconductor switch devices in other electric circuits.

【The invention's effect】

As described above, according to the present invention, the first cylinder is provided with the series-parallel circuit of the plurality of semiconductor switches, and the second cylinder formed of the conductor is arranged inside or outside the first cylinder. Since one end of the series circuit of the semiconductor switch is connected to the cylindrical body, and two supporting rings having a plurality of capacitors connected to the end of the first cylindrical body are provided, the current is evenly distributed to each semiconductor switch. Therefore, the reliability and stability are improved, and the pulse generation circuit including the charge / discharge capacitor can be made compact.

[Brief description of drawings]

FIG. 1 is a side view showing a semiconductor switch device according to a first embodiment of the present invention, FIG. 2 is a sectional front view of the same device, and FIG.
FIG. 4 is a circuit diagram showing a pulse generation circuit using the same device.
FIG. 5 and FIG. 5 are side views of essential parts showing a semiconductor switch device according to second and third embodiments of the present invention, and FIG. 6 is a front view showing a semiconductor switch device according to the fourth embodiment of the present invention. 7 is a sectional side view showing a semiconductor switching device according to a fifth embodiment of the present invention, FIG. 8 is a sectional front view of the same, and FIG. 9 is a circuit diagram showing a pulse generation circuit of a conventional copper vapor laser device. Is. 4a is a capacitor, 8 is a FET, 10 is a first cylinder, 11 is a second
The cylindrical body, 13 and 14 are support rings. In the drawings, the same reference numerals indicate the same or corresponding parts.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshihiro Ueda 8-1-1 Tsukaguchi Honcho, Amagasaki City, Hyogo Prefecture Sanryo Electric Co., Ltd. Central Research Laboratory (72) Shinji Murata 8 Tsukaguchi Honcho, Amagasaki City, Hyogo Prefecture 1-1, Sanryo Electric Co., Ltd., Production Technology Laboratory (72) Inventor Takashi Kumagai 8-1-1, Tsukaguchihonmachi, Amagasaki City, Hyogo Prefecture Sanryo Electric Co., Ltd., Production Technology Laboratory (56) Reference JP 1 -291521 (JP, A)

Claims (1)

[Claims] 1. A first cylinder, a plurality of semiconductor switches arranged in the first cylinder and connected in series and parallel to each other, and the semiconductor switch arranged inside or outside the first cylinder. A second cylindrical body made of a conductor to which one end of the series circuit is connected, and one end of the first cylindrical body fitted at a predetermined interval, and one of the other series circuit of the semiconductor switch A semiconductor switch device comprising: two support rings whose ends are connected; and a plurality of capacitors connected in parallel between the two support rings.