DE202014105674U1 - Contacting device for boards - Google Patents

Abstract

Contacting device for boards comprising a base frame, arranged on the base frame holding means for fixing a board, at least one contact arm, wherein the contact arm is fastened to the base frame and having a contact element, wherein the contact arm with the contact element to a contact point of the board is manually aligned with the Framework-like frame is connected via a hinge, and arranged at another end of this contact arm a probe for contacting a contact point of a circuit board and this contact arm is manually operable.

Description

The present invention relates to a contacting device for boards.

In the development of assemblies usually first individual prototypes are produced, which are soldered and tested by hand. This is especially true for assemblies that are used in small batches, for example, to control certain lights or devices, which are to be produced daily from a few tens to a few hundred pieces.

The function of these prototypes is typically tested manually by contacting a gauge, which is usually an oscilloscope, with one or two probes with corresponding contact points on the assembly. The probes are held by hand. If several contacts are necessary at the same time, then small wires are soldered to the corresponding contact points of the module. At these wires then measuring cables can be fixed by means of clamps.

• 1. Wenn man mit Prüfspitzen, die von Hand gehalten werden, abrutscht, kann man einen Kurzschluss erzeugen, einzelne Leiterbahnen durchtrennen oder die Baugruppe durch Kratzer beschädigen.
• 2. Man kann nicht mehr als zwei Kontaktstellen von Hand kontaktieren, da man nicht mehr als zwei Hände zur Verfügung hat.
• 3. Ein beidseitiges Messen des Prototypens ist sehr schwierig.
• 4. Man muss die Prüfspitzen sehr ruhig halten. Wenn man zittert, kann der Kontakt unterbrochen sein. Hierdurch kann die Messung verfälscht werden. Es kommt daher auch zu Messfehlern.
• 5. Es ist schwierig, über längere Zeit den Kontakt der Prüfspitze mit den Kontaktpunkten aufrechtzuerhalten, wenn die Prüfspitze von Hand gehalten wird.
• 6. Das Anlöten von kleinen Drähten ist nur möglich, wenn der Kontaktpunkt eine gewisse Größe besitzt. Es gibt eine zunehmende Tendenz, die einzelnen Kontaktstellen und Kontaktpunkte sehr klein auszugestalten. Hier ist es praktisch unmöglich, einen Testdraht an der entsprechenden Kontaktstelle anzulöten.

This is the usual procedure for testing prototypes. However, it has significant disadvantages:

• 1. Slipping off with test probes that are held by hand can cause a short circuit, cut through individual tracks, or damage the assembly with scratches.
• 2. You can not contact more than two contact points by hand, because you have not more than two hands available.
• 3. Measuring the prototype on both sides is very difficult.
• 4. You have to keep the probes very quiet. If you tremble, the contact may be interrupted. This can falsify the measurement. It therefore also leads to measurement errors.
• 5. It is difficult to maintain the contact of the probe with the contact points for a long time if the probe is held by hand.
• 6. The soldering of small wires is only possible if the contact point has a certain size. There is an increasing tendency to make the individual contact points and contact points very small. Here it is virtually impossible to solder a test wire to the corresponding pad.

In the mass production of printed circuit boards, however, there are different machines for the automatic testing of printed circuit boards, which can be both populated and unpopulated. Basically, these machines are divided into two groups, the group of finger testers and the group of parallel testers. The finger testers are testers that scan the individual contact points consecutively with individual test fingers and the parallel testers have an adapter with which all contact points are contacted simultaneously.

A finger tester is in the EP 0 468 153 A1 and a method of testing printed circuit boards by means of a finger tester is disclosed in U.S. Patent Nos. 5,467,774 EP 0 853 242 A1 described.

One method of performing connection and short circuit tests is e.g. B. from the EP 0 772 054 A2 or the parallel German application DE 195 41 307 A1 out. This known method is particularly suitable for use with so-called finger testers, which contact the test points of the nets of the circuit boards to be tested with two or more movable test fingers in order to carry out the corresponding electrical measurements. The measurement methods conventionally used in finger testers are the measurement of a resistance or a capacitance. In the EP 0 772 054 A2 the so-called field measurement for the determination of interruptions in the interconnects (connection test) or for the determination of short circuits between the individual interconnects is described.

Furthermore, when testing printed conductors, a so-called four-wire measurement is also carried out in order to measure a line resistance very precisely. For this purpose, contact points with two test fingers each are contacted with a finger tester. The conductor track to be examined is contacted at two printed circuit board test points each with two test probes, whereby one current is fed into the conductor path via one of the test probes of the test probes and the voltage dropping across the conductor track is measured via the other test probe tip. Resistances in the range of less than or equal to 1 ohm can be detected with high reliability.

From the DE 44 41 347 A1 shows a contacting device, which has at least four needles to be used for four-wire measurement.

In the US 6,384,614 B1 a device for carrying out a four-wire measurement by means of two contact tips is disclosed.

The parallel testers have adapters which are always designed specifically for the respective printed circuit board. The structure of such an adapter is z. B. from the EP 0 831 332 A1 out.

In the DE 38 16 019 A1 a device for testing electronic assemblies is described. By using a stylus and the parallel circuit of individual styli to quality inspection properties, such. B. certain high frequency properties, be feasible.

The object of the present invention is to provide a cost-effective and individually adaptable contacting device for printed circuit boards.

To solve this problem, the invention has the features specified in claim 1. Advantageous embodiments thereof are specified in the subclaims.

According to the invention a contacting device for boards is provided. The contacting device comprises a base frame, a holding device arranged on the base frame for fixing a circuit board, at least one contact arm, wherein the contact arm can be fastened to the base frame and has a contact element, wherein the contact arm with the contact element can be aligned manually to a contact point of the circuit board.

The term "manual" means in the context of the present invention without motor drive, d. H. the contact arm is fixed on a contact element by a user by hand with a non-motor driven locking device.

• 1. Die Kontaktelemente müssen nicht von Hand gehalten werden sondern sie behalten eigenständig ihre Position. Hierdurch wird verhindert, dass der Benutzer, abrutscht. Dadurch wird ein Kurschluss sowie das Durchtrennen einzelner Leiterbahnen oder eine sonstige Beschädigung der Baugruppe verhindert.
• 2. Durch das Vorsehen mehrerer Kontaktelemente (Kontaktarm mit mehreren Kontaktelementen, zwei oder mehr Kontaktarme, Programmieradapter) sind zwei oder mehr Kontaktstellen kontaktierbar.
• 3. Ein Kontaktelement ist sicher und wackelfrei auf einem Kontaktfeld anordbar. Dadurch wird verhindert, dass der Kontakt unterbrochen und die Messung verfälscht wird. Messfehler werden sicher und zuverlässig vermieden. Mittels der erfindungsgemäßen Kontaktiervorrichtung wird ein konstanter Kontakt einer Prüfspitze mit einem Kontaktpunkt ermöglicht.
• 4. Der Kontakt zwischen dem Kontaktelement und dem Kontaktpunkt ist beliebig lang aufrechthaltbar, da die Prüfspitze vom Kontaktarm gehalten wird. Somit ist eine exakte dauerhafte Positionierung des Kontaktelements bzw. der Prüfspitze auf dem Kontaktpunkt möglich. Zudem können Messprogramme von beliebiger Dauer ausgeführt und/oder die Platine kann programmiert werden.
• 5. Das Anlöten von Drähten ist nicht notwendig. Die Größe der Kontaktpunkte ist unerheblich.
• 6. Die erfindungsgemäße Kontaktiervorrichtung ist individuell an die unterschiedlichsten Platinen anpassbar und kann auch als Montagerahmen für Platinen verwendet werden.
• 7. Die erfindungsgemäße Kontaktiervorrichtung ist aufgrund ihres Aufbaus sehr einfach und kostengünstig ausgebildet.

By means of the device according to the invention, the following advantages are achieved:

• 1. The contact elements do not need to be held by hand but they retain their position independently. This prevents the user from slipping. This prevents a short circuit as well as the severing of individual tracks or any other damage to the module.
• 2. By providing a plurality of contact elements (contact arm with multiple contact elements, two or more contact arms, programming adapter) two or more contact points are contacted.
• 3. A contact element is safe and wobble-free on a contact field can be arranged. This prevents the contact from being interrupted and the measurement being falsified. Measurement errors are safely and reliably avoided. By means of the contacting device according to the invention a constant contact of a probe is made possible with a contact point.
• 4. The contact between the contact element and the contact point can be maintained as long as desired since the test tip is held by the contact arm. Thus, an exact permanent positioning of the contact element or the probe on the contact point is possible. In addition, measuring programs of any duration can be executed and / or the board can be programmed.
• 5. Soldering of wires is not necessary. The size of the contact points is irrelevant.
• 6. The contacting device according to the invention is individually adaptable to a variety of boards and can also be used as a mounting frame for boards.
• 7. The contacting device according to the invention is very simple and inexpensive due to their construction.

The contacting device according to the invention is particularly suitable for testing small series and prototypes.

The contacting device may have a manually operable locking device for fixed fixing of the contact arm. By the locking device of the contact arm in a precisely defined height in the vertical direction or in a precisely defined distance above the board can be arranged. For this purpose, for example, a sleeve-shaped spacer may be provided. In this way, the contact element fastened to the contact arm, in particular a spring contact element (Pogopin), is arranged with a defined contact force on the contact field.

By means of the manually operable locking device ensures that a probe is fixedly arranged and fixed on a contact point of the board.

The contact arm may be formed of a first arm portion and a second arm portion which are hinged together.

Additionally but in particular alternatively, the contact can be connected at its attachable to the base frame end via a slot with this, so that the contact arm is linearly displaceable.

Due to the two possibilities described above for the formation of the contact arm, it is possible to align the arranged at the end of the contact arm contact element to any contact point of a board.

The contact arm may preferably be formed of printed circuit board material.

Because the contact arm is made of printed circuit board material, it is possible to form conductor tracks for signal detection and signal transmission directly on the contact arm. Due to the board material, the contact arm is also extremely light and can be produced in any shape.

At the contact arm, a connector may be provided which is electrically connected to the contact element is connected, with this connector measuring devices can be connected.

In the context of the present invention, a measuring device is understood to be a voltage and / or current measuring device, a voltage and / or current source, an oscilloscope or a signal generator, etc.

A connector is understood to mean a plug, a socket (also coaxial) or a pin.

The base frame may be formed of profile struts forming a rectangular frame.

The fact that the base frame is formed of profile struts, it is extremely inexpensive to produce in almost any size. Also, the size can be easily and inexpensively, as needed, changed.

The rectangular frame may have at its vertices Profilfußstreben, which are perpendicular to a plane defined by the frame plane.

The footrests may extend in one or both directions away from the plane of the base frame. As a result, a two-sided measurement of the module is possible.

By Profilfußstreben inventive contacting is standing, lying and obliquely usable.

A standing use of the contacting device is understood to mean that the plane spanned by the rectangular frame is arranged at 90 ° to the horizontal.

A horizontal use of the contacting device is understood to mean that the plane spanned by the rectangular frame is arranged parallel to the horizontal.

Furthermore, on one or both sides of the frame, the foot braces may be formed at two adjacent corner points shorter or longer than at the two opposite corner points. In this way, an inclined relative to the horizontal arrangement of the plane defined by the profile struts level realize.

This facilitates the testing and editing of the board, as a more ergonomic position or arrangement of the board is made possible.

Furthermore, by providing tread struts which extend in both directions away from the plane of the base frame, it is possible to machine a board on both sides.

In a preferred embodiment, the foot braces are slidably connected to the frame, for example via angle profiles and sliding nuts. In this way, any of the uses described above with the contacting device is possible.

The holding device for fixing a circuit board may have a snap device. The snap device may have a holding mechanism designed as an eccentric or a spring-loaded holding mechanism.

By the holding device no mounting holes on the board are necessary to fix them in the contactor. Accordingly, also boards can be tested with Randnaher placement.

An electronic circuit for signal conditioning or detection can be arranged on the contact arm and / or on the base frame.

The electronic circuit for signal conditioning or detection may include a programmable signal generator, a frequency converter, a current or voltage converter and / or a signal amplifier, wherein a plurality of identical and / or different elements may be provided.

The contacting device according to the invention may also have two or more contact arms.

Characterized in that two or more contact arms are provided, a plurality of contact points of a circuit board can be contacted.

The contact arms may have one, two or more contact elements for double and / or multiple contact in common pitches.

By providing a plurality of contact arms and / or contact elements by means of the contacting device according to the invention, a four-point measurement can be performed.

For this purpose, four contact elements are provided. The conductor track to be examined is contacted at two printed circuit board test points each with two contact elements, wherein a current is fed into the conductor track via one of the contact elements at a circuit board test point and the voltage drop across the conductor track is measured via the other contact elements. This can be used with high reliability resistors in the Range of less than or equal to 1 ohm are detected.

To perform the four-point measurement, a four-point probe can be used.

In order to carry out the four-point measurement, it is also possible to provide a probe which replaces two contact elements. The probe is designed such that two contact elements in a tip with a large cross section, z. B. a conical tip are connected. This tip is z. B. formed of a gold or copper alloy, so that the tip has a very low resistance. At a contact element of the probe is then a power source and to the other contact element is then connected a voltmeter. By providing two such a probe, the four-point measurement by means of the contacting device according to the invention can also be carried out at very small printed circuit board test points or contact points, since only a single tip must be brought into contact with the printed circuit board test point.

By means of the device according to the invention it is also possible to determine the high-frequency properties of the printed conductors of a printed circuit board. For this purpose, the impedance of printed conductors is measured by means of a high-frequency signal. One known method is time domain reflectometry (TDR), in which a voltage signal is applied to the respective network to be measured and then the duration of one or more reflections of the signal is measured. For this purpose, so-called time domain reflectometers are used, which are special oscilloscopes that apply a voltage to the grid and show the change in this voltage within a certain period of time. The time domain reflectometry is similar to that of the radar or sonar principle, in which signals are emitted and reflections are evaluated. In the case of time domain reflectometry, the transmitted signal is a voltage that runs along a track.

The contact arms or their contact elements can be connected to an active electronics for differential measurement, that is to say that the test probes can be connected to a differential amplifier with fixed or programmable amplification.

A multiple and permanent contact allows programming and debugging a board with individual arrangement of the contact points.

For this purpose and for further measurements, a programming adapter can be arranged on two opposite profile struts of the rectangular frame or on two profile struts arranged parallel to one another and connected to the rectangular frame. On the programming adapter, a multiple connector may be provided.

Alternatively, a specific Mehrfachkontaktarm may also be provided.

The programming adapter can transmit an enable signal, a ground signal, a supply signal and / or at least one programming signal.

Furthermore, an in-circuit test is also possible with the contacting device according to the invention. In this case, one or more predetermined signals are transmitted via a contact element and via a further contact element, the response (response) of the circuit is tapped.

At the contact arm, a connection in the form of a plug, which is connected via a line section with the contact element, be provided for connection to a corresponding measuring electronics.

This connection is preferably removed from the contact tip, so that fewer forces are transmitted to the spring tip when inserting and removing the measuring electronics.

Furthermore, the cables can be connected to the base frame via strain relief elements, so that the cables are plugged into delicate plugs without damaging them.

At the end of the contact arm, a temperature measuring head such as an NTC can be arranged.

Thus, the contact elements may be connected to an active electronics for temperature detection.

On the base frame and / or on the contact arm terminal and connector strips, preferably with strain relief for safe connection and connection to a measuring electronics can be integrated.

Furthermore, the contacting device may have a mechanical lifting / lowering device for the defined lifting and lowering of the contact arm.

The contact arms can be arranged at different heights. For this purpose, it is only necessary that differently long contact elements or test probes are arranged at their ends.

The invention will be explained in more detail below with reference to the drawings. These show in:

1 a representation of a contacting device according to the invention in a schematic view,

2 a detailed view of in 1 illustrated contacting device,

3 a contacting device according to the invention in a perspective view,

4 an eccentric lever in a plan view of a holding device of the contacting, and

5 a base element of the holding device in a perspective view.

In the following, a contacting device according to the invention 1 described with reference to an embodiment ( 1 to 4 ).

The contacting device 1 includes a base frame 2 , one on the base frame 2 arranged holding device 3 for fixing a circuit board and a contact arm 4 with a contact element 5 which is manually alignable on a contact point of a board.

The contact element may be a probe, a spring probe, a probe, a contact tip or a four-point probe, and so on. The contact element may be fastened to the contact arm at a predetermined angle, inclined with respect to the vertical.

The contacting device described below 1 can be used both lying and standing. The terms lying and standing are explained in more detail below.

The base frame 2 is made of two parallel spaced-apart longitudinal struts 6 , which also has two transverse struts, also spaced apart from each other in parallel 7 connected to each other are formed such that the longitudinal struts 6 and the cross struts 7 the rectangular base frame 2 form.

The longitudinal struts 6 and the cross struts 7 are formed from T-slot profiles which are square in cross-section and have a longitudinal groove on each side wall 8th for inserting sliding square head screws have.

The cross struts 7 are with the longitudinal struts 6 over angle profiles 9 connected, wherein the angle profiles by means of the grooves 8th arranged square head screws and connecting elements are connected such that the longitudinal struts survive at all four corners of the rectangular frame. This section of the longitudinal struts 6 is called supernatant 10 designated.

At these supernatants 10 are foot struts 11 arranged, which are also formed of profile struts. The foot struts 11 are at the supernatants 10 by means of appropriate angle profiles 9 attached.

In the present embodiment, it is provided that the foot struts 11 in the area of a crossbar 7 extend from the plane defined by the rectangular frame plane at right angles down. The in the area of the other cross strut 7 arranged footstays 11 on the other hand extend perpendicularly from the plane spanned by the rectangular frame both down and up.

By means of such trained foot struts, it is possible, the contactor 1 lying, as in the 1 and 2 shown to use, with the downwardly extending struts 11 all have the same length, so that the contacting device can be arranged on a horizontal base, such as a work table, parallel to its surface ( 1 to 3 : Operation lying).

The fact that two of the foot braces extend both upwards and downwards, is also a setting up of the device 1 on these two struts 11 possible, so that the plane spanned by the rectangular frame plane is now perpendicular to a surface of a work table ( 3 : Standing).

Furthermore, between the longitudinal struts 6 and between the cross struts 7 parallel to the cross struts 7 extending struts 12 on the base frame by means of appropriate angle profiles 9 attached.

In the central area of the struts 12 is the holding device 3 arranged for fixing a board. The holding device 3 comprises four retaining means, each consisting of a base element 13 and an ejector lever 14 are formed.

The basic element 13 includes a mounting portion 15 with a through hole 16 over the the base element 13 in a corresponding groove 8th the striving 12 is fixed.

Furthermore, the base element 13 two storage legs 17 formed, which extend in the vertical direction. In the storage legs 17 is the ejector lever 14 rotatably mounted.

The ejector lever 14 is formed in an approximately S-shaped, wherein an actuating leg 18 for actuating or tilting the holding lever 14 around a rotation axis 19 is formed and an ejector leg 20 for clamping and ejecting a board is formed.

A board support formed on the ejector leg is designed in such a way that the support surface is designed to be very narrow, so that even boards with assembly near the edge can be fixed. A vertical stop surface is made to rest at an angle <90 ° to ensure secure clamping different board material and at the same time to prevent the board from sliding upwards.

In the area between the struts 12 is on adapter struts 21 a programming adapter 22 locatable.

The contact arm 4 is from a first arm section 23 and a second arm portion 24 trained, over a joint 25 connected to each other. The arm sections 23 . 24 are each made of two superimposed and parallel strip-shaped elements 26 educated. Around the two strip-shaped elements 26 To keep at a distance corresponding sockets (not shown) are provided.

The contact arm 4 or its strip-shaped elements 26 are made of board material.

An end of the first arm section 23 is about a locking device, which is formed for example as a screw with thumbwheel, in a groove 8th a cross strut 7 attached. By actuating or tightening the knurling wheel, the contact arm is arranged and fixed in a precisely defined height in the vertical direction or at a precisely defined distance above the circuit board. To define the height, for example, a sleeve-shaped spacer may be provided. In this way, the contact element fastened to the contact arm, in particular a spring contact element (Pogopin), is arranged with a defined contact force on the contact field.

In this case, both the contact arm and / or the contact element can exert a spring force.

Furthermore, the locking device can be designed as a quick release with eccentric.

At the other end of the first arm section 23 this is also articulated via a knurled screw with one end of the second arm portion 24 connected. The other end of the second arm section 24 has a contact element 5 , For example, a probe for contacting a contact point of a board on.

Furthermore, on the longitudinal struts 6 and / or the cross struts 7 further, in particular at least one further contact arm 4 be arranged (not shown). The further contact arm 4 is according to the contact arm described above 4 educated.

In the band-shaped elements 26 of the second section 24 a contact arm 4 At least one trace is formed to receive data from the probe 28 towards one on the second arm portion 24 arranged plug connection 29 transferred to. At the plug connection 29 a corresponding plug of a cable of a test device can be inserted.

On the programming adapter 22 a corresponding plug is also provided for connection to the test device.

The contact arms can be positioned at any point of a generally rectangular test field. To contact a contact point of a circuit board to be tested, the contact arms along the respective struts 6 . 7 displaceable, so that the contact element can be placed from above or from below onto the contact point of the printed circuit boards.

Furthermore, the contacting device may have a mechanical lifting / lowering device for the defined lifting and lowering of the contact arm. The lifting / lowering device may, for example, have a slotted guide and an actuating lever to allow the defined raising and lowering of the contact arm.

The mechanical lifting / lowering device may also be formed integrally with the locking device in a single device.

Furthermore, the contacting device can have a magnifying glass in order to be able to examine details of the test field more precisely.

By connecting a measuring device to the connector of a contact element and / or the programming adapter, the measurements described above can be carried out by means of the contacting device according to the invention.

LIST OF REFERENCE NUMBERS

1

contacting

3

holder

4

contact

5

contact element

6

longitudinal strut

7

crossmember

8th

groove

9

angle section

10

Got over

11

Fußstrebe

12

holding strut

13

base element

14

ejector

15

attachment section

16

Through Hole

17

storage legs

18

actuating lever

19

axis of rotation

20

holding leg

21

adapter strut

22

programming adapter

23

first arm section

24

second arm section

25

joint

26

band-shaped element

27

thumbscrew

28

probe

29

connector

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 0468153 A1 [0006]
• EP 0853242 A1 [0006]
• EP 0772054 A2 [0007, 0007]
• DE 19541307 A1 [0007]
• DE 4441347 A1 [0009]
• US 6384614 B1 [0010]
• EP 0831332A1 [0011]
• DE 3816019 A1 [0012]

Claims (13)

Contacting device for boards comprising a base frame, a arranged on the base frame holding means for fixing a circuit board, at least one contact arm, wherein the contact arm is attachable to the base frame and having a contact element, wherein the contact arm with the contact element to a contact point of the board is manually aligned with the framework-like frame is connected via a hinge , And arranged at another end of this contact arm a probe for contacting a contact point of a circuit board and this contact arm is manually operable. Contacting device according to claim 1, characterized in that a manually operable locking device for fixed fixing of the contact arm is provided. Contacting device according to claim 1 or 2, characterized in that the contact arm of a first arm portion and a second two arm portion is formed, which are hinged together, or that the contact arm is connected at its attachable to the base frame end via a slot with this, so that the contact arm is linearly displaceable. Contacting device according to one of claims 1 to 3, characterized in that the contact arm is formed of printed circuit board material. Contacting device according to one of claims 1 to 4, characterized in that the base frame is formed of profile struts, which form a rectangular frame. Contacting device according to claim 5, characterized in that the rectangular frame has at its vertices Profilfußstreben which are perpendicular to a plane defined by the frame plane, wherein the Fußstreben extend in one or both directions from the plane of the base frame. Contacting device according to one of claims 1 to 6, characterized in that the holding device for fixing a circuit board has at least one snap device. Contacting device according to one of claims 1 to 7, characterized in that the holding device is attached to two opposite profile struts of the rectangular frame or to two mutually parallel and connected to the rectangular frame profile struts. Contacting device according to one of claims 1 to 8, characterized in that a mechanical lifting / lowering device for the defined raising and lowering of the lever arm is provided. Contacting device according to one of claims 1 to 9, characterized in that a programming adapter is arranged on the base frame such that it contacts at least one contact element of a circuit board. Contacting according to one of claims 1 to 10, characterized in that a connector is provided on the contact that is electrically connected to the contact element, said measuring devices are connected to this connector. Contacting device according to one of claims 1 to 11, characterized in that the contact arm, an electronic circuit for signal detection or conditioning is arranged. Contacting device according to one of claims 1 to 12, characterized in that the base frame, an electronic circuit for signal detection or conditioning is arranged.

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