JP3482868B2 - Power supply - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device which converts a DC power supply into a high frequency output and supplies it to a load.

[0002]

2. Description of the Related Art As a power supply device of this type, as shown in FIG. 15, a first printed circuit board 3a on which a power supply circuit for rectifying an output of an AC power supply to obtain a predetermined direct current output and a direct current of the power supply circuit are mounted. The second printed circuit board 3b, on which a high-frequency circuit that converts the output to a high-frequency output and supplies the load to the load, is mounted, and the metal shield case 1 is formed such that their mounting surfaces face each other.
The one housed in 0'is proposed (Actual Kaihei 3-8).
804). Here, the shield case 1
Reference numeral 0'denotes the first divided body 1 whose upper surface is opened in FIG.
0a and a second divided body 10 having an open lower surface in the same figure.
It is formed by combining with b, and two shield plates 11a and 11b are arranged in the shield case 10 ', and the first printed board 3a is included in the first divided body 10a. It is arranged in a space surrounded by the peripheral surface and the first shield plate 11a, and the second printed circuit board 3b is surrounded by the inner peripheral surface of the second divided body 10b and the second shield plate 11b. It is arranged in space.

As shown in FIG. 16 (a), a rectangular box-shaped shielding member 12 (FIG. 1) having an opening on one surface of a printed circuit board 3'on which a power supply circuit and a high frequency circuit are mounted.
7) is attached so as to cover the high-frequency circuit and is housed in a rectangular box-shaped shield case 10 ″ (see Japanese Patent Laid-Open No. 9-19164). Here, the shielding member 12 is provided. As shown in FIG. 17, a plurality of connecting pieces 12a are projected from the opening edge, and the connecting pieces 12a are inserted into the connecting holes 3c formed in the printed circuit board 3 ′,
It is soldered to the conductive pattern 3d formed on the back surface of the printed circuit board 3'shown in (b).

[0004]

By the way, in each of the above conventional configurations, the power supply circuit and the high frequency circuit are spatially separated from each other to reduce mutual interference due to electromagnetic induction between the power supply circuit and the high frequency circuit. By housing the circuit and the high frequency circuit in the shield case 10 ′ (or the shield case 10 ″), it is possible to prevent the high frequency noise generated from the high frequency circuit from leaking to the outside.

However, the power supply device shown in FIG. 15 requires two printed circuit boards 3a and 3b, and moreover, each printed circuit board 3a and 3b has a shield plate 11a and a shield plate 11a.
11b is provided, and further, each printed circuit board 3a, 3
b and the shield plates 11a and 11b are connected to the corresponding divided bodies 10a and 10b by screws 15 and then the divided bodies 10a and 10b are joined, so that the number of parts is large and the structure is complicated and the assembling is easy. There is a problem that it is bad.

Further, in the power supply device shown in FIG. 16, in addition to the shield case 10 ″, a rectangular box-shaped shielding member 12 having an opening on one side is required, and the connecting piece 12 a of the shielding member 12 is connected to the printed circuit board 3 ′. Since it is necessary to insert it into the connection hole 3c and solder it, the cost increases and the assemblability is poor.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a power supply device which does not malfunction due to noise and is easy to assemble.

[0008]

In order to achieve the above-mentioned object, the invention of claim 1 is a power supply circuit for outputting a DC voltage, and a load by converting the output of the power supply circuit into a high frequency output.
A high frequency circuit for supplying to the electrodeless discharge lamp, wherein the one printed board in which each circuit is mounted, a shield case body, wherein the printed circuit board a box shape is housed, which has an opening on one side, the sheet Rudokesu body To close the opening surface of
It said sheet and a Rudokesu shield case lid is attached to the body, to opposite from one side to the one side said to the printed circuit board is spatially divide the region in which the circuit component is mounted on the
That the Sri consisting notch towards the side Tsu isolation portion is formed and the bisected one region was high-frequency circuit is disposed, the sheet Rudokesu body corresponds to the slit portion and the high frequency circuit and the binary and shield plate disposed between the other disposed in the region by the circuit component is made integrally formed, the shield plate, the shield cable
The side wall and bottom wall of the main body
In the space surrounded by the shield case body and the shield case lid, the shield plate is interposed between the high frequency circuit and the power source circuit, so that the electromagnetic wave between the power source circuit and the high frequency circuit is induction can prevent mutual interference due, moreover, at the time of assembling, by accommodating a single printed circuit board to the shield case body, a shield plate formed integrally with the shield case body the flop
From one side of the lint board to the side opposite to that side
Since thus interposed between the power supply circuit and the high-frequency circuit through the ground Tsu preparative portion made of cormorants notch facilitates assembly. In addition, the shield plate is
Since it is continuously and integrally formed from the side wall and bottom wall,
Easy positioning of the printed circuit board with respect to the case body
become.

The invention of claim 2 outputs a DC voltage.
The power supply circuit and the output of the power supply circuit are converted to high frequency output
A high-frequency circuit for supplying a load and a circuit in which each circuit is mounted.
Box-shaped with two printed circuit boards and an opening on one side
A shield case body in which the printed circuit board is housed,
The cover should be set so as to cover the opening surface of the shield case body.
Includes a shield case lid attached to the main body
Well, the operating frequency of the high frequency circuit is 13.56MHz
Yes, the printed circuit board has an area where circuit components are mounted.
A slit part that spatially bisects is formed and
The high-frequency circuit is arranged in one of the
A continuous part that connects the areas divided by the slit part
Circuit parts that are not easily affected by noise are installed near the
The shield case body corresponds to the slit part.
Also, it is arranged in the other area divided into the high frequency circuit
The shield plate that is placed between the circuit components
And the shield plate is formed of
It is formed by continuously and integrally forming the side wall and the bottom wall of the main body,
An electrolytic capacitor for direct current smoothing which constitutes a part of the power supply circuit
The high-frequency circuit is placed on the shield plate
Characterized in that it is arranged in the space on the side of
Enclosed by the shield case body and the shield case lid.
In a closed space, there is a shield between the high frequency circuit and the power supply circuit.
There is a shield plate between the power supply circuit and the high frequency circuit.
Mutual interference due to the electromagnetic induction of
Also, the printed circuit board was divided into two by the slit portion.
The vicinity of the continuous part that connects the regions is affected by noise.
Since difficult circuit parts are installed, the power circuit and high frequency
More reliable malfunction due to noise interference with the wave circuit
The electrolytic capacitor can be
In the space where the high-frequency circuit is installed with respect to the shield plate
Since it is installed, switching elements and electrolytic capacitors
The distance from the service can be shortened and the assembly
Sometimes, one printed circuit board is used as the shield case body.
Formed integrally with the shield case body by storing
The shield plate is connected to the power circuit and high frequency through the slit part.
Easy to assemble because it is interposed between the wave circuit
become. Further, since the shield plate is continuously and integrally formed from the side wall and the bottom wall of the shield case body, the printed circuit board can be easily positioned with respect to the shield case body .

[0010]

[0011]

[0012]

[0013]

[0014]

[0015] The invention of claim 3 is the invention of claim 1, wherein the printed circuit board, a continuous portion hardly circuit components near the influence of noise of the connecting regions together, which is bisected by the slits unit distribution because it is set, it is possible to more reliably prevent erroneous operation due to noise interference between each other and the power supply circuit and the high-frequency circuit.

[0016] The invention of claim 4 is the invention of claim 3, parts that are disposed in the vicinity of the continuous portion, since electrolytic capacitor for DC smoothing constituting part of the power supply circuit, the high In the frequency circuit, the distance between the switching element that is switched at high frequency and the electrolytic capacitor can be shortened, and malfunction due to noise from the pattern wiring can be prevented.

[0017] The invention of claim 5 is the invention of claim 4, wherein the electrolytic capacitor is with respect to the shield plate
Since the high-frequency circuit is disposed in a space on the side to be disposed, it is possible to further shorten the distance between the switching element and the electrolytic capacitor.

The invention of claim 6 relates to claim 2 or claim
In the invention of 4 or claim 5, since the capacitor for high frequency noise elimination is connected in parallel with the electrolytic capacitor is disposed, by the capacitor for high frequency noise elimination is disposed, said high frequency circuit It is possible to more reliably prevent malfunction due to noise generated from the.

[0019] The invention of claim 7 is the invention of claim 6, the capacitor for the high-frequency noise removing is characterized in that it is arranged at a position apart from the high-frequency circuit than the electrolytic capacitor.

The invention of claim 8 is from claim 1 to claim
In seventh invention, the a control circuit for controlling the output power of the high frequency circuit, control circuit,且one in spaces on the side where the high-frequency circuit to the shield plate in the sheet Rudokesu body is disposed the because it is disposed between the high-frequency circuit and the power circuit, the distance between the high frequency circuit and the power supply circuit control circuit by placing between said RF circuit and said power supply circuit spreading, it is possible to reduce the noise that the noise from the high frequency circuit on the power supply circuit, further, a pattern between the high frequency circuit and the control circuit by the control circuit is disposed in the vicinity of the high frequency circuit Wiring can be shortened.

[0021] The invention of claim 9 is the invention of claim 8, wherein the printed circuit board, since the ground pattern of the control circuit is provided on the entire portion where components are mounted which constitutes the control circuit can the control circuit reliably prevented from malfunctioning at the noise from the high <br/> frequency circuit.

[0022]

The invention of claim 10 is the invention of claim 1, wherein the printed circuit board is with respect to the slits unit
The area of one side of the high-frequency circuit is disposed is, is larger than the area of the other side, before Te the print substrate smell
Serial high frequency circuit makes it possible to widen the ground pattern by the increasing the area of the side to be disposed, prior to
The high frequency circuit Te carboxymethyl Rudokesu body odor can be reduced the effect of noise on the side are disposed.

The invention of claim 11 is the invention of claim 1 to claim 10, wherein the shield case body, the front
One side of the volume of the space in which two spaces sac Chi said high <br/> frequency circuit which is more separated carboxymethyl Rudo plate is disposed is, is greater than the volume of the other side of the space, the high-frequency It is possible to reduce the temperature rise in the space on one side where the circuit is arranged.

According to a twelfth aspect of the present invention, in the first to eleventh aspects of the present invention, the power supply circuit converts an output of an AC power supply into a DC output, and inputs AC power from the AC power supply. wherein a power supply line, and a cable for supplying high-frequency output of the high frequency circuit to the load, the connection portion between the printed circuit board and the power supply line, the straight line connecting the connecting portion between the cable and the printed circuit board since the shield plate is disposed, it can be made less the effect of high frequency noise from the cable has on the power line, so as not to adversely affect the power line or al the power circuit.

A thirteenth aspect of the present invention is characterized in that, in the first to twelfth aspects of the present invention, the operating frequency of the high frequency circuit is 13.56 MHz.

According to a fourteenth aspect of the present invention, a power supply circuit that generates a DC output voltage across a smoothing capacitor that is an electrolytic capacitor, a high frequency circuit that converts the output of the power supply circuit into a high frequency output and supplies the high frequency output to a load, and One printed circuit board on which a circuit is mounted, a box-shaped shield case body having an opening on one surface and in which the printed circuit board is housed,
A shield case lid attached to the shield case body so as to cover the opening surface of the shield case body, wherein the printed circuit board is provided with a slit portion that spatially bisects a region where a circuit component is mounted, A high-frequency circuit is disposed in one of the divided regions, and the shield case main body is disposed corresponding to the slit portion and disposed between the high-frequency circuit and the circuit component disposed in the other divided region. plate is formed continuously and integrally on the side wall and bottom wall of the shield case body, said smoothing capacitor with a print substrate the smoothing capacitor in the vicinity of the continuous portion connecting between regions that have been divided by the slit portion is disposed A high-frequency circuit and a connection point where a capacitor for removing high-frequency noise is placed in parallel with the power supply line for supplying AC power to the power supply circuit. Which is characterized in that the shield plate is present between the connection points of the cables for supplying a high-frequency output to the load is connected, in a space surrounded by the shield case body and the shield case lid,
A shield plate is interposed between the high frequency circuit and the power supply circuit, and the smoothing capacitor and the high frequency noise removing capacitor are arranged in the vicinity of the continuous portion connecting the areas divided by the slit portion on the printed circuit board. Therefore, it is possible to prevent mutual interference between the power supply circuit and the high frequency circuit due to electromagnetic induction, and it is possible to reduce the influence of noise generated from the cable on the power supply line. By accommodating the printed circuit board in the shield case main body, the shield plate integrally formed in the shield case main body is interposed between the power supply circuit and the high frequency circuit through the slit portion, which facilitates the assembly.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) FIG. 3 shows a circuit diagram of an embodiment of a power supply device of the present invention. The power supply device of the present embodiment supplies high frequency power to the electrodeless discharge lamp 70 that is a load.

The electrodeless discharge lamp 70 is provided with a bulb 70a made of a light-transmissive material such as glass in which an inert gas, a metal vapor alone or a mixed gas is sealed as a discharge gas.
An induction coil 70b is arranged near the valve 70a. Various shapes have been proposed for the shape of the valve 70a and the arrangement of the induction coil 70b.
It is assumed that the induction coil 70b is arranged outside 0a. The discharge gas is adjusted so as to mainly generate ultraviolet rays, and a fluorescent material is applied to the inner peripheral surface of the bulb 70a.

The power supply device shown in FIG. 3 is a rectifier circuit DB including a diode bridge for full-wave rectifying an AC power source AC such as a commercial power source, and a rectifier circuit DB which converts the output of the rectifier circuit DB into a predetermined DC voltage and outputs the DC voltage. 1 DC power supply circuit E ₁ , a second DC power supply circuit E ₂ for converting the output of the rectifier circuit DB into a predetermined DC voltage and outputting the same, and a pair of switching elements Q ₂ and Q _{3 formed} of power MOSFETs in series. A main amplifier 34 which has a circuit and converts the output of the first DC power supply circuit E ₁ into a high frequency output and supplies it to the induction coil 70b by turning on and off the switching elements Q ₂ and Q ₃ at a high frequency;
A crystal oscillator circuit 31 using a crystal oscillator, a preamplifier 32 for amplifying the output of the crystal oscillator circuit 31 including a switching element Q ₁ made of a MOSFET, and a drive for driving the switching elements Q ₂ , Q ₃ via a transformer T. Circuit 33
And a matching circuit 50 provided between the induction coil 70b and the main amplifier 34. Further, a high frequency blocking filter circuit FL is inserted between the AC power source AC and the rectifier circuit DB. The high frequency output terminal of the main amplifier 34 is connected to the matching circuit 50 via the coaxial cable 6.
It is connected to the. In short, the high frequency output of the main amplifier 34 is supplied to the electrodeless discharge lamp 70 through the coaxial cable 6 and the matching circuit 50.

Although the electrodeless discharge lamp 70 is used as the load in this embodiment, the load is not limited to the electrodeless discharge lamp 70. Further, the main amplifier 34 is
The output of the preamplifier 32 is supplied between the gate and the source of each of the switching elements Q ₂ and Q ₃ via the transformer T to perform class D amplification. The inductor L ₁₁ and the capacitor C ₁₁ are connected in series. High frequency power is output through the resonance circuit.

In this embodiment, the filter circuit F
L, the rectifier circuit DB, the first DC power supply circuit E ₁ , and the second DC power supply circuit E ₂ constitute the power supply circuit 20, the crystal oscillation circuit 31, the preamplifier 32, etc. constitute the drive circuit 33, and the drive circuit 33. The main amplifier 34 constitutes the high frequency circuit 30.

The first DC power supply circuit E ₁ uses a step-up chopper circuit and includes a first inductor (not shown), a first transistor (not shown), and a first diode (not shown). , A first capacitor C consisting of an electrolytic capacitor
₁ (first smoothing capacitor), a first chopper control circuit (not shown) for controlling ON / OFF of the first transistor, and the like. That is, the first DC power supply circuit E ₁ generates a counter electromotive force in the first inductor by turning on and off the first transistor, and stores the counter electromotive force in the first capacitor C ₁ to perform boosting. ing. Further, the second DC power supply circuit E ₂ uses a step-down chopper circuit, and includes a second transistor (not shown) and a second transistor (not shown).
Second capacitor C consisting of an inductor (not shown), a second diode (not shown), and an electrolytic capacitor
₂ (second smoothing capacitor), a second chopper control circuit (not shown) for controlling on / off of the second transistor, and the like. That is, the second DC power supply circuit E ₂ generates a stepped down voltage across the second capacitor C ₂ . Then, from the AC power supply AC to the rectifier circuit D
Since the input current to B can continue to flow at a high frequency, there is no pause period in the input current, and the input can be performed by simply inserting a simple filter circuit FL between the AC power supply AC and the rectifier circuit DB. The current waveform can be made continuous, and the input current distortion can be reduced.

The preamplifier 32 is composed of a class C amplifier circuit using the switching element Q ₁ , and the main amplifier 34 is composed of a class D amplifier circuit using the pair of switching elements Q ₂ and Q ₃ . .

Further, the matching circuit 50 has an appropriate impedance viewed from the high frequency circuit 30 when the electrodeless discharge lamp 70 is stably lit so that high frequency power can be efficiently transmitted when the electrodeless discharge lamp 70 is stably lit. Designed to be value.

Therefore, in the power supply device of this embodiment, the high frequency power output from the high frequency circuit 30 is supplied to the coaxial cable 6.
To the electrodeless discharge lamp 70 side through the electrodeless discharge lamp 7
0 is turned on. In other words, from the high frequency circuit 30 to the induction coil 1b, several hundred kHz to several tens MHz (for example, the operating frequency of the high frequency circuit 30 is 1
By applying a high-frequency current of 3.56 MHz), a high-frequency electromagnetic field is generated in the induction coil 70b, high-frequency power is supplied to the electrodeless discharge lamp 70, and a high-frequency plasma current is generated in the bulb 70a to generate ultraviolet rays or It is designed to generate visible light.

By the way, the power supply circuit 20 and the high frequency circuit 30 of the circuit shown in FIG. 3 are mounted on the rectangular printed board 3 shown in FIGS. 1 and 2, and the metal shield case shown in FIG. Delivered within 10. The shield case 10 is in the shape of a rectangular box having an opening on one side, and has a shield plate body 1 in which the printed circuit board 3 is housed, and a rectangular plate shape which is coupled to the shield case body 1 so as to close the opening surface of the shield case body 1. It is configured with a shield case lid 8.

The printed circuit board 3 is provided with a slit portion 4 which is a narrow notch portion extending from the central portion of one of the four sides toward the side opposite to the one side, and is more than the slit portion 4 in FIG. In the first region 3 ₁ on the left side, the circuit components of the power supply circuit 20 except the first capacitor C ₁ and the second capacitor C ₂ are arranged. The high frequency circuit 30 is disposed in the second region 3 ₂ on the right side than the slit portion 4 in FIG. 2,
The second area 3 ₂ further includes a second area 3 ₂ and a first area 3
_{The first} capacitor C ₁ and the second capacitor C ₂ are arranged in the vicinity of the narrow third region 3 ₃ (continuous portion) connecting ₁ and ₁ .

On the other hand, the shield case body 1 is integrally provided with a metallic shield plate 2 at a position corresponding to the slit portion 4 of the printed circuit board 3, and the printed circuit board 3 is housed in the shield case body 1. In this state, since the shield plate 2 is interposed between the first area 3 ₁ and the second area 3 ₂ , mutual interference due to noise between the power supply circuit 20 and the high frequency circuit 30 is prevented. can do.
Here, the shield plate 2 is continuously and integrally formed from the bottom wall and the side wall of the shield case body 1. The printed circuit board 3 is fixed to the shield case body 1 by inserting the screws 16 into the holes 3e formed at the four corners and screwing the screws 16 into the screw holes 1e of the shield case body 1.

Further, in the present embodiment, a metallic separation shield plate 7 which is positioned on the same straight line as the shield plate 2 is arranged between the side edge of the shield plate 2 and the side wall of the shield case body 1. Here, the separation shield plate 7 is attached to the shield plate 2 by a metal screw 17, and the shield plate 2 has a screw hole in a notch 2a formed at an end portion in the longitudinal direction. 2b is formed, and the separation shield plate 7 is integrally provided with a mounting piece 7a which is mounted on the cutout portion 2a of the shield plate 2 and has a hole 7b through which the screw 17 is inserted. Here, the separation shield plate 7 contacts both the shield plate 2 and the inner side surface of the shield case body 1. Since the shield plate 2 and the separation shield plate 7 are interposed between the power supply circuit 20 and the high frequency circuit 30, and the shield plate 2 and the separation shield plate 7 have the same potential, the power supply circuit 20 and the high frequency circuit Mutual interference due to electromagnetic induction with the circuit 30 can be reliably prevented.

Further, in the present embodiment, the length H ₁ of the shield plate 2 in the longitudinal direction is made longer than the length H ₂ of the separation shield plate 7, so that the gap between the power supply circuit 20 and the high frequency circuit 30 is increased. Since the power consumption is reduced, malfunction due to noise interference between the power supply circuit 20 and the high frequency circuit 30 is unlikely to occur. The high frequency circuit 3 of the printed circuit board 3
The area of the second region 3 ₂ on the side where 0 is mounted is set to the power supply circuit 2
Since the area of the first region 3 ₁ on the side where 0 is arranged is larger than that of the first region 3 ₁ , the ground pattern on the printed circuit board 3 on the side of the high frequency circuit 30 can be widened, and the noise of the high frequency circuit 30 can be reduced. The impact can be reduced. Further, in the shield case 10, the high-frequency circuit 3 is provided with respect to the shield portion composed of the shield plate 2 and the separation shield plate 7.
Since the volume of the space on the side where 0 is disposed is made larger than the volume of the space on the side where the power supply circuit 20 is disposed, the temperature rise of the high frequency circuit 30 can be reduced.

Further, as shown in FIG. 4, by arranging the first capacitor C ₁ and the second capacitor C ₂ in the vicinity of the _third region 3 ₃ (continuous portion) of the printed circuit board 3,
Leakage noise between the power supply circuit 20 and the high frequency circuit 30 in the space where the shield plate 2 does not exist can be reduced. Further, the distance between the switching element Q ₁ of the preamplifier 32 and the first capacitor C ₁ of the first DC power supply circuit E ₁ can be reduced, and the switching elements Q ₂ and Q ₃ of the main amplifier 34 and the second DC power supply can be reduced. Since the distance between the circuit E ₂ and the second capacitor C ₂ can be reduced,
It is possible to prevent malfunction due to noise from the pattern wiring. Further, as shown in FIG. 4, by arranging in parallel a capacitor C ₀ for removing high frequency noise on the input side of each of the first capacitor C ₁ and the second capacitor C ₂ , the high frequency circuit 30 A malfunction due to noise on the power supply circuit 20 side can be prevented.

Further, in the present embodiment, in the printed circuit board 3, a portion to which the electric wire 5 for supplying the AC power supply AC to the rectifier circuit DB is connected via the high frequency blocking filter circuit FL, and the high frequency circuit section. The coaxial cable 6 for supplying the high-frequency output of 30 to the electrodeless discharge lamp 70, which is a load, is disposed substantially on the same straight line, and the shield plate 2 is interposed therebetween, so that the coaxial cable 6 is coaxial. It is possible to prevent high-frequency noise from the cable 6 from entering the AC power supply AC side through the power supply line 5.

By the way, at the time of assembly, the printed circuit board 3 is housed in the shield case body 1 and fixed by the screw 16, and the power supply line 5 and the cable 6 are connected to predetermined positions of the printed circuit board 3, and then the separation shield plate 7 is provided. Is attached to the shield plate 2 with the screw 17, and then the shield case lid 8 is attached to the shield case body 1.
To attach the shield case lid 8 to the shield case body 1, for example, a screw or the like may be used.

Therefore, in the power supply device of this embodiment, the other members can be assembled to the shield case body 1 from one direction, and the split body 1 can be assembled as in the conventional example shown in FIG.
The number of parts can be reduced and the assembling can be facilitated as compared with the case where the divided bodies 10a and 10b are joined after the printed boards 3a and 3b and the shield plates 11a and 11b are attached by the screws 15 for each 0a and 10b. In addition, FIG.
Since the work of inserting the connection piece of the shielding member 12 into the printed circuit board 3 and soldering the same as in the conventional example shown in FIG.

(Embodiment 2) FIG. 5 shows a circuit diagram of a power supply device of this embodiment. The basic circuit configuration of the present embodiment is substantially the same as that of the first embodiment shown in FIG. 3, except that a control circuit 40 for controlling the output of the high frequency circuit 30 is provided, and thus the same as the first embodiment. The same reference numerals are given to the constituent elements, and the description thereof will be partially omitted.

In the control circuit 40, when the electrodeless discharge lamp 70 which is a load is not connected (that is, when there is no load), an overcurrent flows in the high frequency circuit section 30 and the switching element Q _{2 of} the main amplifier 34, It has a protective function to prevent the destruction of Q ₃ . The control circuit 40 includes a resistor R for detecting overcurrent.
_X, the comparator CP, a pair of resistor R ₁ connected to the second ends of the capacitor C ₂ of the second DC power supply circuit E _2, R ₂
, And the connection point of the resistor R _X and the capacitor C ₃ is connected to the positive terminal of the comparator CP, and the resistor R ₁ and the resistor R ₂ are connected to the negative terminal of the comparator CP.
The connection point with is connected. That is, a voltage obtained by dividing the output voltage of the second DC power supply circuit E ₂ by the resistors R ₁ and R ₂ is input to the negative terminal of the comparator CP as a reference voltage. Thus, it becomes no load, the excessive current flows than in the normal lighting to the resistance R _X for overcurrent detection, the voltage of the capacitor C ₃ is increased, the voltage of the capacitor C ₃ exceeds the reference voltage The output of the comparator CP changes from low level to high level, and the switching element Q ₄ is turned on. When the switching element Q ₄ is turned on, the gate and source of the switching element Q ₁ of the preamplifier 32 are short-circuited via the diode D ₂ , so that the preamplifier 3
The oscillation of No. 2 is stopped, and as a result, the oscillation of the main amplifier 34 is stopped, so that the switching elements Q ₂ , Q ₃ and other circuit parts can be prevented from being destroyed.

As shown in FIG. 6, the control circuit 40 is arranged on the same printed circuit board 3 as the power supply circuit 20 and the high frequency circuit 30, but the high frequency circuit 30 is mounted in the slit portion 4. It is arranged so as to be located between the power supply circuit 20 and the high frequency circuit 30 in the second region 3 ₂ .
Further, since the ground pattern on the printed circuit board 3 of the control circuit 40 is formed on almost the entire surface, it is possible to prevent the control circuit 40 from malfunctioning due to high frequency noise from the high frequency circuit 30.

Therefore, in the present embodiment, the control circuit 40
Is disposed between the power supply circuit 20 and the high frequency circuit 30, the high frequency circuit 30 and the power supply circuit 20 can be separated from each other to the extent that they are not electromagnetically coupled, and the noise from the high frequency circuit 30 affects the power supply circuit 20. Can be reduced.

FIG. 7 shows the first DC power supply circuit E ₁ (however,
(Excluding the first capacitor C ₁ ) and the second DC power supply circuit E ₂
(However, the second capacitor C ₂ is excluded), drive circuit 3
3, the main amplifier 34, the control circuit section 40, the first capacitor C ₁ of the first DC power supply circuit E _1, with on the second DC power supply circuit the second printed circuit board 3 such as a capacitor C ₂ of E ₂ It is the figure which showed the example of arrangement | positioning, the connection location of the electric wire 5 for inputting the alternating current power from the alternating current power supply AC, and the electrodeless discharge lamp 7.
0 is connected to the coaxial cable 6 for supplying high-frequency power to the third area 3 ₃ (continuous portion) of the printed circuit board 3.
Is arranged so that both connection points are on the same straight line, and there is a slit portion 4 between both connection points.
Moreover, since the shield plate 2 is present in the state of being housed in the shield case 10, it is possible to prevent high frequency noise from the coaxial cable 6 from entering the AC power source AC side through the power source line 5. When the printed circuit board 3 is housed in the shield case 10, the printed circuit board 3 is
The separation shield plate 7 is arranged in a part of the third region 3 ₃ . In addition, A in FIG. 7 indicates a rectification unit including a filter circuit FL and a rectification circuit DB.

(Third Embodiment) The circuit configuration of this embodiment is the same as that of the second embodiment, and as shown in FIG. 8 or 9, the second region 3 ₂ separated by the slit portion 4 of the printed circuit board 3 is used. A slit portion 4'is provided between the portion where the control circuit 40 is provided and the portion where the drive circuit 33 and the main amplifier 34 are provided, and the shield plate corresponding to the slit portion 4'is provided in the shield case body 1. (Not shown)
Is characterized in that the high-frequency noise generated in the drive circuit 33 and the main amplifier 34 is generated by the control circuit 40.
Can be prevented from affecting. In the state where the OsameSo the printed circuit board 3 in the shield case 10, so that the separation shield plate 7 is arranged in the region of the third region 3 ₃ of the printed circuit board 3. 8 and 9
A is a high frequency blocking filter circuit FL and rectifier circuit DB
The rectification part which consists of. The same components as those in the second embodiment are designated by the same reference numerals and the description thereof will be omitted.

(Embodiment 4) The circuit configuration of the power supply device of this embodiment is the same as that of the second embodiment, and is characterized by the shape of the printed circuit board 3 and the arrangement of circuit components shown in FIG. In addition,
The same components as those in the above embodiment are designated by the same reference numerals.

In this embodiment, the slit portions 4 are formed from a pair of opposing sides of the printed circuit board 3,
The pair of slit portions 4 are formed on the same straight line. In addition, the shield case body 1 has slit portions 4
The pair of shield plates 2 are integrally provided so as to correspond to.

Further, in the present embodiment, the first capacitor C ₁ and the second capacitor C ₂ are formed in the central portion of the printed board 3 in the _second region 3 ₂ on the right side of the printed board 3 in FIG. It is arranged in the vicinity of the formed third region 3 ₃ (continuous portion).

Also in this embodiment, the connection point of the power supply line 5 and the connection point of the coaxial cable 6 are arranged so as to be far from the third region 3 ₃ .

(Fifth Embodiment) The basic configuration of the present embodiment is substantially the same as that of the fourth embodiment, and as shown in FIG. 11, in the first region 3 ₁ of the printed circuit board 3, the first DC power supply circuit E is provided. _A filter circuit F is provided between ₁ and the second DC power supply circuit E _2.
It is characterized in that a rectifying unit A composed of L and a rectifying circuit DB is provided, and it is possible to reduce the influence of mutual induction between the first DC power supply circuit E ₁ and the second DC power supply circuit E _2. it can. The same components as those in the fourth embodiment are designated by the same reference numerals.

(Sixth Embodiment) The circuit configuration of the power supply device of this embodiment is the same as that of the second embodiment, and is characterized by the shape of the printed circuit board 3 and the arrangement of circuit components shown in FIG. In addition,
The same components as those in the above embodiment are designated by the same reference numerals, and the description thereof will be omitted.

In this embodiment, the slit portion 4 formed of a rectangular long hole is formed in the central portion of the printed circuit board 3, and the shield case 2 is provided with the shield plate 2 at a position corresponding to the slit portion 4. The shield plates 7 are integrally provided so as to project, and separate shield plates 7 are provided between both side edges of the shield plate 2 and the inner surface of the shield case body 1 facing each other. Further, in the present embodiment, the first capacitor C ₁ and the second capacitor C ₂ are arranged in the second region 3 ₂ of the printed board 3 near both ends of the slit portion 4 in the longitudinal direction. In the present embodiment, the distance between the control circuit 40 and the second DC power supply circuit E ₂ that is the power supply of the control circuit 40 can be reduced, the pattern wiring between them can be shortened, and the main amplifier 34 and the main amplifier 34 can be shortened. Since the distance from the _first DC power supply circuit E ₁ which is the power supply of 34 can be reduced and the pattern wiring between them can be shortened,
It is possible to prevent malfunction due to the influence of noise from the pattern wiring.

(Embodiment 7) The basic configuration of this embodiment is substantially the same as that of Embodiment 6, and as shown in FIG. 13, in the first region 3 ₁ of the printed circuit board 3, the first DC power supply circuit E is provided. _A filter circuit F is provided between ₁ and the second DC power supply circuit E _2.
It is characterized in that a rectifying unit A composed of L and a rectifying circuit DB is provided, and it is possible to reduce the influence of mutual induction between the first DC power supply circuit E ₁ and the second DC power supply circuit E _2. it can. The same components as those in the sixth embodiment are designated by the same reference numerals.

(Embodiment 8) The basic configuration of this embodiment is substantially the same as that of Embodiment 7, and as shown in FIG. 14, three slit portions 4 are formed on the same straight line and correspond to each slit portion 4. It is characterized in that the shield plate 2 is formed integrally with the shield case body 1. In this embodiment, the separate shield plates 7 are arranged between the shield plates 4. The same components as those in the above-described embodiment are designated by the same reference numerals and the description thereof will be omitted.

[0061]

According to the first aspect of the present invention, a power supply circuit for outputting a DC voltage and an output of the power supply circuit are converted into a high-frequency output and a negative voltage is output.
A high-frequency circuit to be supplied to the electrodeless discharge lamp as a load, one printed circuit board on which each circuit is mounted, a box-shaped shield case body having an opening on one surface, and the printed circuit board being housed therein, and a shield case lid which is attached to the sheet Rudokesu body so as to close the opening of the sheet Rudokesu body, said printed circuit board said one side from one side so as to spatially divide the region in which the circuit component is mounted
Said the opposite is ground Tsu isolation portion made of a notch towards the sides is formed and the bisected one region was high-frequency circuit is disposed, the sheet Rudokesu body and correspondingly and the high frequency circuit to the slit portion A shield plate disposed integrally with the circuit component disposed in the other divided region is integrally formed, and the shield plate is the seal.
It is formed continuously and integrally from the side wall and bottom wall of the case body.
The shield plate is interposed between the high frequency circuit and the power supply circuit in the space surrounded by the shield case body and the shield case lid, so that mutual interference by electromagnetic induction between the power supply circuit and the high frequency circuit. It can be prevented, moreover, at the time of assembling, by accommodating a single printed circuit board to the shield case body, a shield plate formed integrally with the shield case body the printed circuit board
A notch extending from one side to the side opposite to the one side.
Since thus interposed between the power supply circuit and the high-frequency circuit through Li Cheng ground Tsu isolation portion, there is an effect that assembly is facilitated. The shield plate is a shield case.
It is integrally formed from the side wall and bottom wall of the main body.
Position the printed circuit board with respect to the shield case body.
It has the effect of making it easier.

The invention of claim 2 outputs a DC voltage.
The power supply circuit and the output of the power supply circuit are converted to high frequency output
A high-frequency circuit for supplying a load and a circuit in which each circuit is mounted.
Box-shaped with two printed circuit boards and an opening on one side
A shield case body in which the printed circuit board is housed,
The cover should be set so as to cover the opening surface of the shield case body.
Includes a shield case lid attached to the main body
Well, the operating frequency of the high frequency circuit is 13.56MHz
Yes, the printed circuit board has an area where circuit components are mounted.
A slit part that spatially bisects is formed and
The high-frequency circuit is arranged in one of the
A continuous part that connects the areas divided by the slit part
Circuit parts that are not easily affected by noise are installed near the
The shield case body corresponds to the slit part.
Also, it is arranged in the other area divided into the high frequency circuit
The shield plate that is placed between the circuit components
And the shield plate is formed of
It is formed by continuously and integrally forming the side wall and the bottom wall of the main body,
An electrolytic capacitor for direct current smoothing which constitutes a part of the power supply circuit
The high-frequency circuit is placed on the shield plate
The shield is installed in the space on the
Smell surrounded by case body and shield case lid
The shield plate between the high frequency circuit and the power supply circuit.
Therefore, due to electromagnetic induction between the power supply circuit and the high frequency circuit
Mutual interference can be prevented, and the printing substrate
The plate connects the areas divided by the slit part.
Circuit parts that are not easily affected by noise are placed near the continuous section.
Since it is installed,
It is possible to more reliably prevent malfunctions due to noise interference.
Also, the electrolytic capacitor is
It is installed in the space where the high-frequency circuit is installed.
With the distance between the switching element and the electrolytic capacitor
It can be shortened, and at the time of assembly, one
By storing the printed circuit board in the shield case body
The shield plate that is integrally formed with the shield case body.
Through the slit between the power supply circuit and the high frequency circuit.
Since it will be present, the effect that it will be easier to assemble
There is. Further, since the shield plate is continuously and integrally formed from the side wall and the bottom wall of the shield case body, there is an effect that the positioning of the printed circuit board with respect to the shield case body becomes easy.

[0063]

[0064]

[0065]

[0066] The invention of claim 3 is the invention of claim 1, wherein the printed circuit board, a continuous portion hardly circuit components near the influence of noise of the connecting regions together, which is bisected by the slits unit distribution because it is set, there is an effect that it is possible to more reliably prevent erroneous operation due to noise interference between each other and the power supply circuit and the high-frequency circuit.

[0067] The invention of claim 4 is the invention of claim 3, parts that are disposed in the vicinity of the continuous portion, since electrolytic capacitor for DC smoothing constituting part of the power supply circuit, the high In the frequency circuit, there is an effect that the distance between the switching element that is switched at high frequency and the electrolytic capacitor can be shortened, and malfunction due to noise from the pattern wiring can be prevented.

[0068] The invention of claim 5 is the invention of claim 4, wherein the electrolytic capacitor is with respect to the shield plate
Since the high-frequency circuit is disposed in a space on the side to be disposed, there is an effect that it is possible to further shorten the distance between the switching element and the electrolytic capacitor.

The inventions of claims 6 and 7 are
In the invention of claim 2 or claim 4 or claim 5 , since a capacitor for removing high frequency noise that is connected in parallel to the electrolytic capacitor is provided , by providing the capacitor for removing high frequency noise , there is an effect that it is possible to reliably prevent malfunction due to noise generated from the high frequency circuit.

The invention of claim 8 is from claim 1 to claim
In seventh invention, the a control circuit for controlling the output power of the high frequency circuit, control circuit,且one in spaces on the side where the high-frequency circuit to the shield plate in the sheet Rudokesu body is disposed the because it is disposed between the high-frequency circuit and the power circuit, the distance between the high frequency circuit and the power supply circuit control circuit by placing between said RF circuit and said power supply circuit spreading, it is possible to reduce the noise that the noise from the high frequency circuit on the power supply circuit, further, a pattern between the high frequency circuit and the control circuit by the control circuit is disposed in the vicinity of the high frequency circuit The effect is that the wiring can be shortened.

[0071] The invention of claim 9 is the invention of claim 8, wherein the print substrate, parts ground pattern of said control circuit constituting said control circuit is provided on the entire portion being mounted since the control circuit there is an effect that it is possible to prevent the high <br/> from malfunctioning reliably noise from frequency circuit.

[0072]

[0073] The invention of claim 10 is the invention of claim 1, wherein the printed circuit board is with respect to the slits unit
The area of one side of the high-frequency circuit is disposed is, is larger than the area of the other side, before Te the print substrate smell
Serial high frequency circuit makes it possible to widen the ground pattern by the increasing the area of the side to be disposed, prior to
There is an effect that the high-frequency circuit Te carboxymethyl Rudokesu body odor can be reduced the effect of noise on the side are disposed.

[0074] The invention of claim 11 is the invention of claim 1 to claim 10, wherein the shield case body, the front
One side of the volume of the space in which two spaces sac Chi said high <br/> frequency circuit which is more separated carboxymethyl Rudo plate is disposed is, is greater than the volume of the other side of the space, the high-frequency There is an effect that the temperature rise in the space on one side where the circuit is arranged can be reduced.

According to a twelfth aspect of the present invention, in the first to eleventh aspects of the present invention, the power supply circuit converts an output of an AC power supply into a DC output, and inputs AC power from the AC power supply. wherein a power supply line, and a cable for supplying high-frequency output of the high frequency circuit to the load, the connection portion between the printed circuit board and the power supply line, the straight line connecting the connecting portion between the cable and the printed circuit board since the shield plate is arranged, and possible to reduce the influence of high frequency noise from the cable has on the power line, there is an effect that the power supply line or al the power circuit can be made to not adversely affect.

According to a fourteenth aspect of the present invention, a power supply circuit that generates a DC output voltage across a smoothing capacitor that is an electrolytic capacitor, a high frequency circuit that converts the output of the power supply circuit into a high frequency output and supplies the high frequency output to a load, and One printed circuit board on which a circuit is mounted, a box-shaped shield case body having an opening on one surface and in which the printed circuit board is housed,
A shield case lid attached to the shield case body so as to cover the opening surface of the shield case body, wherein the printed circuit board is provided with a slit portion that spatially bisects a region where a circuit component is mounted, A high-frequency circuit is disposed in one of the divided regions, and the shield case main body is disposed corresponding to the slit portion and disposed between the high-frequency circuit and the circuit component disposed in the other divided region. plate is formed continuously and integrally on the side wall and bottom wall of the shield case body, said smoothing capacitor with a print substrate the smoothing capacitor in the vicinity of the continuous portion connecting between regions that have been divided by the slit portion is disposed A high-frequency circuit and a connection point where a capacitor for removing high-frequency noise is placed in parallel with the power supply line for supplying AC power to the power supply circuit. Since the shield plate exists between the connection point to which the cable for supplying the high-frequency output to the load is connected, the space between the high-frequency circuit and the power supply circuit is surrounded by the shield case body and the shield case lid. Since the shield plate is interposed between them, and the printed circuit board is provided with the smoothing capacitor and the capacitor for removing high frequency noise in the vicinity of the continuous part connecting the areas divided by the slit part, It is possible to prevent mutual interference due to electromagnetic induction with a high-frequency circuit, reduce the effect of noise generated from the cable on the power supply line, and use one printed circuit board as the shield case body during assembly. By storing it, the shield plate formed integrally with the shield case body passes through the slit part and the high frequency circuit and high frequency. Since thus interposed between the circuit, there is an effect that assembly is facilitated.

[Brief description of drawings]

FIG. 1 is a schematic exploded perspective view showing a first embodiment.

FIG. 2 is a schematic configuration diagram of a main part of the above.

FIG. 3 is a circuit diagram of the same.

FIG. 4 is a schematic explanatory view of a main part of the above.

FIG. 5 is a circuit diagram showing a second embodiment.

FIG. 6 is a schematic explanatory diagram of a main part of the above.

FIG. 7 is an explanatory diagram of an example of circuit arrangement on the printed circuit board.

FIG. 8 is a diagram illustrating the circuit arrangement example on the printed circuit board according to the third embodiment.

FIG. 9 is an explanatory diagram of another circuit arrangement example of the same.

FIG. 10 is a diagram illustrating a circuit arrangement example on a printed circuit board according to the fourth embodiment.

FIG. 11 is an explanatory diagram of a circuit arrangement example on a printed circuit board according to the fifth embodiment.

FIG. 12 is a diagram illustrating a circuit arrangement example on a printed circuit board according to the sixth embodiment.

FIG. 13 is an explanatory view of the circuit arrangement example on the printed circuit board according to the seventh embodiment.

FIG. 14 is an explanatory diagram of the circuit arrangement example on the printed circuit board according to the eighth embodiment.

FIG. 15 is a schematic configuration diagram showing a conventional example.

FIG. 16 is a schematic configuration diagram showing another conventional example.

FIG. 17 is an explanatory diagram of a main part of the above.

[Explanation of symbols]

1 Shield Case Main Body 2 Shield Plate 3 Printed Circuit Board 3 ₁ First Area 3 ₂ Second Area 3 ₃ Third Area 7 Separation Shield Plate 8 Shield Case Lid 10 Shield Case

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yufuku Akira 1048 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Works, Ltd. (56) Reference JP-A-8-223914 (JP, A) JP-A-9-148776 (JP, A) JP 5-259683 (JP, A) JP 11-299260 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02M 7/48 H02M 7 / 538 H05B 41/24

Claims (14)

(57) [Claims] 1. A power supply circuit for outputting a DC voltage, and an electrodeless discharge which is a load by converting the output of the power supply circuit into a high frequency output.
A high-frequency circuit to be supplied to the lamp, one printed circuit board on which each of the circuits is mounted, a box-shaped shield case body having an opening on one surface, and the printed circuit board being housed therein ,
And a shield case lid which is attached to the sheet over <br/> Rudokesu body so as to close the open face of the sheet Rudokesu body, said printed circuit board so as to divide the region in which the circuit component is mounted spatially From one side to the side opposite to that side
The high frequency circuit is disposed on one region of Sri Tsu isolation portion is formed by and said bisected consisting notch Cow, the sheet <br/> Rudokesu body corresponding to the slit portion and the and the radio frequency circuit The shield plate, which is arranged between the circuit component arranged in the other area divided into two, is integrally formed.
The shield plate is on the side of the shield case body.
A power supply device comprising a wall and a bottom wall that are integrally formed . 2. A power supply circuit for outputting a DC voltage and a power supply circuit.
High frequency that converts the output of the road to high frequency output and supplies it to the load
Circuit and one printed circuit board on which each circuit is mounted
And a box-shaped printed circuit board having an opening on one surface thereof
And the shield case that stores the
In the shield case body so as to cover the opening surface of the main body
And a shield case lid to be attached, the high-frequency circuit
The operating frequency of 13.56MHz, the print
The board spatially divides the area where the circuit components are mounted into two parts.
A lit portion is formed and is placed in front of one of the two divided areas.
The high-frequency circuit is installed and the slit section creates two
The shadow of noise near the continuous part that connects the divided regions.
Circuit parts that are hard to receive
The main body corresponds to the slit portion and the high frequency circuit.
Between the circuit component arranged in the other area divided into two
The shield plate is integrally formed from the side wall and the bottom wall of the shield case body, and a part of the power supply circuit is formed.
The electrolytic capacitor for DC smoothing that composes is the shield
Arranged in the space where the high-frequency circuit is arranged with respect to the plate
A power supply device comprising: 3. The printed circuit board is provided in the slit portion.
Noise is added near the continuous part that connects the two bisected regions.
Power apparatus according to claim 1, wherein less susceptible circuit components's is characterized by comprising disposed. 4. The parts arranged in the vicinity of the continuous portion are
An electrolytic capacitor for direct current smoothing which constitutes a part of the power supply circuit
The power supply device according to claim 3, wherein the power supply device is a sensor . 5. The electrolytic capacitor is the shield plate.
Is installed in the space on the side where the high-frequency circuit is installed.
Power supply according to claim 4, characterized by comprising been. 6. A capacitor connected in parallel to the electrolytic capacitor.
The power supply device according to claim 2, 4 or 5, further comprising a capacitor for removing frequency noise . 7. The capacitor for removing high frequency noise is
Places further away from the high frequency circuit than the electrolytic capacitor
Power supply of claim 6 Symbol mounting, characterized by comprising disposed on location. 8. A control for controlling the output power of the high frequency circuit.
Control circuit inside the shield case body
At which the high-frequency circuit is arranged with respect to the shield plate
And the power supply circuit and the high frequency circuit
The power supply device according to claim 1, wherein the power supply device is disposed between the power supply device and the power supply device. 9. The printed circuit board is a group of the control circuit.
The parts that make up the control circuit are mounted on the land pattern.
9. The power supply device according to claim 8, wherein the power supply device is provided over the entire portion . 10. The printed circuit board includes the slit portion.
With respect to the area on one side where the high frequency circuit is arranged,
Claim, characterized in that larger than the area of the other side 1
The power supply described. 11. The shield case body is made of the sheet metal.
The high frequency circuit out of the two spaces separated by the shield plate.
The volume of the space on one side where the road is arranged is
Power supply of claim 1 to請 Motomeko 10, wherein the even larger Ri by volume. 12. The power supply circuit outputs the output of an AC power supply as a direct current.
AC power from an AC power supply that is converted to output
Power line for inputting the high frequency output of the high frequency circuit.
A cable for supplying force to the load,
The connection point between the printed circuit board and the power line, the cable and
The seal is placed on the straight line connecting the connection point with the printed circuit board.
2. A contract plate is provided and the contract plate is arranged.
The power supply device according to claim 11 . 13. The operating frequency of the high frequency circuit is 13.
The power supply device according to claim 1, wherein the power supply device has a frequency of 56 MHz . 14. A smoothing capacitor comprising an electrolytic capacitor
Power supply circuit that generates a DC output voltage across the
High frequency that converts the output of the road to high frequency output and supplies it to the load
Circuit and one printed circuit board on which each circuit is mounted
And a box-shaped printed circuit board having an opening on one surface thereof
The main body of the shield case and the book
Attached to the shield case body so as to block the opening surface of the body
And a shield case lid, wherein the printed circuit board is a circuit
The slit part that spatially divides the area where the parts are mounted into
A high-frequency circuit is formed in one of the divided regions.
It is installed, the shield case body corresponds to the slit part
And is arranged in the other area divided into two parts with the high frequency circuit.
The shield plate that is placed between the circuit components
It is formed continuously and integrally on the side wall and bottom wall of the case body.
The substrate is divided into two parts by the slit part.
The smoothing capacitor is arranged in the vicinity of the continuous portion to be connected.
High-frequency noise is removed in parallel with the smoothing capacitor.
A removal capacitor is provided to supply AC power to the power supply circuit.
High-frequency circuit and connection point to connect the power line for power supply
A cable is connected to supply the high frequency output of the
The shield plate to that power supplies, characterized in that exists between the connection points to.