JP2011123735A - Electronic apparatus and driving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inexpensively provide a transmission system which can be satisfactorily operated against the increase of contact resistance. <P>SOLUTION: In an electronic apparatus which is operated by generating a DC voltage from electric signals input from a first connection terminal and a second connection terminal which are disposed on the driving device side, a first apparatus-side terminal being in contact with the first connection terminal and a second apparatus-side terminal being in contact with the second connection terminal are formed like surfaces having a prescribed area, and a clamping circuit for limiting a voltage applied to an internal circuit of the electronic apparatus to a prescribed value and a rectifier circuit for converting electric signals inputted to the first apparatus-side terminal and the second apparatus-side terminal to a DC voltage are provided, and the first connection terminal and first apparatus-side terminal and the second connection terminal and second apparatus-side terminal can be connected by conductor connection or both conductor connection and capacity connection via a capacitance formed between terminals in parallel. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electronic device and a drive device, and more particularly to a technique suitable for use in transmitting power and data signals from a drive device to an electronic device via a contact terminal.

  In general, in the case of a data carrier for short-range communication, it does not have a power source, and the operating power is operated by using the power sent from the reader / writer device as the power source. In such a data carrier system, the connection with the reader / writer device is roughly classified into a non-contact type and a contact type.

  As a conventional example of a contact type data carrier, for example, in Patent Document 1, there is a contact type data carrier that communicates with a reader / writer unit by transmitting three signals of power, clock, and data through a two-wire interface. Proposed.

  Contacts and connectors are used for the connection between the contact data carrier and the reader / writer device, but the connection is required to be able to be easily and reliably turned on and off. However, if the connection state lasts for a long period of time, the electrode at the connection part becomes dirty, affected by foreign matter, or the contact electrode oxidizes, resulting in contact failure, which makes it impossible to reliably turn on and off. .

  In order to solve such problems, there are contrivances such as gold-plating the electrodes, making the connection part a sealed structure to prevent dust, etc., and making the contact part springy. Sometimes done. However, this configuration has a problem that the cost of the data carrier increases. Therefore, it is conceivable to stabilize the power supply to the internal circuit by providing a voltage regulator on the data carrier after increasing the drive voltage instead of devising the connection portion.

FIG. 4 shows an example of a contact-type transmission system in which a voltage regulator is provided on the data carrier.
In FIG. 4, reference numeral 41 denotes a reader / writer device, and 42 denotes a data carrier. The reader / writer device 41 and the data carrier 42 are connected via a first contact portion P1 and a second contact portion P2, and a contact transmission system. Is configured.

  The first contact portion P1 includes a first reader / writer contact P11 and a first data carrier contact P12. The second contact portion P2 includes a second reader / writer contact P21 and a second data carrier contact P22. An internal circuit 421 is connected via a diode D0 between the first data carrier contact P12 and the second data carrier contact P22.

  A voltage regulator 422 is disposed between the power supply terminal A of the internal circuit 421 and the diode D0. Further, a first capacitor C41 and a second capacitor C42 are connected in parallel with the internal circuit 421. The first capacitor C41 has one side connected between the diode D0 and the voltage regulator 422, and the other side connected to the second data carrier contact P22 and connected in parallel with the internal circuit 421. The second capacitor C42 has one side connected between the voltage regulator 422 and the power supply terminal A of the internal circuit 421 and the other side connected to the second data carrier contact P22 in parallel with the internal circuit 421. It is connected.

  In order to supply the internal circuit 421 with a pulse signal transmitted from the reader / writer device 41 via the first contact part P1, the signal input terminal B of the internal circuit 421 and the anode side of the diode D0 are connected. Further, the reference potential terminal E of the internal circuit 421 and the second data carrier contact P22 are connected.

  In the reader / writer device 41, a drive circuit 411 that supplies a voltage higher than the operating pressure of the internal circuit 421 is connected to the first reader / writer terminal P11, and a reference potential 412 is connected to the second reader / writer terminal P21. Has been. The drive circuit 411 supplies power for driving the internal circuit 421 of the data carrier 42 via the first contact part P1 and the second contact part P2. As described above, when the voltage regulator 422 is provided, the allowable range of contact resistance in the first contact portion P1 and the second contact portion P2 can be widened.

JP 2003-208583 A

  As described above, if the drive voltage is increased and the voltage regulator 422 is provided in order to allow a large contact resistance in the first contact portion P1 and the second contact portion P2, the cost of the data carrier 42 is increased. Therefore, when applied to a data carrier that requires a low price with a simple configuration, there is a significant problem in terms of cost.

For example, when the operating voltage of the internal circuit is 3.3 V, the operating current is 0.3 mA, and the power consumption is 1 mW, the total contact resistance at the first contact portion P1 and the second contact portion P2 is allowed up to 1000 KΩ. For this purpose, a drive voltage of 300 V or more is required. For this reason, since it is necessary to use the voltage regulator 422 having an allowable input of 300 V or more, the cost of the data carrier is increased.
In view of the above-described problems, an object of the present invention is to provide an electronic device and a driving device that can operate even when contact resistance is increased at low cost.
It is a second object of the present invention to provide a transmission system that can operate satisfactorily even when the contact resistance increases and the driving force to the electronic device decreases.
Furthermore, it is a third object to further suppress the jump of signals to the surroundings.

An electronic apparatus according to the present invention is an electronic apparatus that operates by generating a DC voltage from an electric signal input from a first connection terminal and a second connection terminal arranged on the driving device side. A first device-side terminal that contacts the first connection terminal; a second device-side terminal that contacts the second connection terminal; and a space between the first device-side terminal and the second device-side terminal. An internal circuit connected to the internal circuit, a clamp circuit connected in parallel with the internal circuit and limiting a voltage applied to the internal circuit to a predetermined value, and the first device side terminal and the second device side terminal A rectifier circuit that converts an input electrical signal into a DC voltage, and the first device side terminal and the second device side terminal are configured in a planar shape having a predetermined area. Connection terminal and first device side terminal, and second connection terminal and second device Among the capacitive connection via the capacitance formed when the contact is increased due to the gap between the terminal and the conductor connection and the high resistance foreign object is sandwiched or tilted or deformed, and the contact resistance increases. It is characterized in that it is possible to connect conductor connections or both in parallel.
Another feature of the electronic apparatus according to the present invention is that the rectifier circuit is disposed between the first connection terminal and the second connection terminal and a power input terminal of the internal circuit. 1 rectifier circuit, a second rectifier circuit disposed between the first connection terminal and the second connection terminal and the signal input terminal of the internal circuit, the first connection terminal and the second connection terminal. The connecting terminal is disposed between the clamp circuit and the clamp circuit.
Another feature of the electronic device according to the present invention is that a coil that resonates in parallel with the frequency of the drive signal together with the equivalent input capacitance of the device is provided between the first connection terminal and the second connection terminal. It is connected.

The drive device of the present invention is a drive device that outputs a high-frequency electrical signal via a first device-side terminal and a second device-side terminal arranged on the electronic device side, and the first device A first connection terminal that contacts the side terminal, a second connection terminal that contacts the second device side terminal, and a signal connected between the first connection terminal and the second connection terminal An output circuit; an electric signal generation circuit that outputs a high-frequency electric signal output from the first connection terminal and the second connection terminal to the signal output circuit; and the electric signal generation circuit and the signal output circuit. A matching circuit disposed between the signal output circuit and the matching circuit to form a parallel resonance circuit, and the resonance voltage of the parallel resonance circuit is set between the first connection terminal and the second connection circuit. Vary depending on the load impedance connected to the connection terminal. It is characterized in.
According to another feature of the driving apparatus of the present invention, the parallel resonant circuit includes a contact between the first connection terminal and the first device side terminal, and the second connection terminal. If the load impedance connected to the resonance circuit is large due to poor contact with the second device side end, the resonance voltage of the parallel resonance circuit is increased, both contacts are good and the contact When the load impedance is small, the resonance voltage of the parallel resonance circuit is lowered.
Another feature of the present invention is that the first connection terminal and the second connection terminal are formed in a planar shape having a predetermined area, and the first device-side terminal and the first connection terminal are formed. The connection terminal and the second device-side terminal and the second connection terminal can be connected in parallel in conductor connection or both of conductor connection and capacitive connection.
Another feature of the present invention is that the signal output circuit outputs a high-frequency electrical signal in a differential manner.

  A transmission system according to the present invention includes the electronic device described above and the drive device described above.

According to the electronic apparatus of the present invention, the terminal for connecting the drive device is configured in a planar shape having a predetermined area, and the conductor connection and the capacitor connection to the terminal of the drive device are the conductor connection or both in parallel. In addition to enabling connection and limiting the voltage fluctuation due to fluctuations in the resistance value of the connection terminal to the specified range by the clamp circuit, when the resistance value in the conductor connection increases due to contamination on the connection terminal part It is possible to form a connection circuit by capacitive connection. Thereby, the electronic device which can ensure the electrical connection in a contact part reliably can be provided.
According to the driving device of the present invention, the first connection terminal that comes into contact with the first device-side terminal disposed on the electronic device side, and the second device-side terminal disposed on the electronic device side. The second connection terminal that comes into contact, the signal output circuit connected between the first connection terminal and the second connection terminal, and the first connection terminal and the second connection terminal output the signal. An electric signal generation circuit for outputting a high-frequency electric signal to the signal output circuit, and a matching circuit disposed between the electric signal generation circuit and the signal output circuit are provided, and the signal output circuit and the matching circuit The parallel resonance circuit is configured to change the resonance voltage of the parallel resonance circuit according to the load impedance connected to the first connection terminal and the second connection terminal. If the contact is normal, By load impedance of the road is reduced, the lower the amplitude of the parallel resonant circuit, the first connection terminal and the excessive voltage to the second connection terminal can be prevented from being output. Also, if the contact part is incomplete and the contact resistance increases and the load impedance increases, the drive voltage increases, so even if the contact resistance value of the contact part increases, the electronic device can be driven well can do.
According to the transmission system of the present invention, in the state where the electronic device and the driving device are connected, even if the resistance value of the connection terminal varies, the electrical connection state between the electronic device and the driving device is improved. Even if the value of the contact resistance at the contact portion increases, the driving device can drive the electronic device satisfactorily through a large contact resistance and capacitance parallel circuit.
Further, since driving is performed with a differential high-frequency electric signal, jumping from the signal line to the surroundings due to capacitive coupling can be suppressed.

It is a figure which shows embodiment of this invention and shows the structural example of a transmission system. It is a figure which shows embodiment of this invention and shows the 1st modification of a transmission system. It is a figure which shows embodiment of this invention and shows the 2nd modification of a transmission system. It is a figure which shows a prior art example and shows the structural example of a transmission system.

Next, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a diagram illustrating a configuration example of a transmission system according to the first embodiment of this invention. The transmission system according to the present embodiment includes a contact reader / writer device 110 as a driving device that outputs a high-frequency electrical signal, and a contact data carrier 120 as an electronic device. The reader / writer device 110 and the data carrier 120 is connected via a first connection terminal device T1 and a second connection terminal device T2 (hereinafter referred to as contacts T1 and T2).

  The first connection terminal device T1 is provided on the electronic device side with the first connection terminal T11 connected to the reader / writer device 110 side (drive device side), and the power input of the internal circuit 121 on the data carrier 120 side The terminal A includes a first device side terminal T12 connected via a rectifier circuit 123. The first connection terminal T11 and the first device side terminal T12 have a predetermined area in order to face the connection partner with a predetermined area. In this way, the surface connection makes it possible to electrically connect the reader / writer device 110 and the data carrier 120 in a direct current and alternating current manner as will be described later.

  The second connection terminal device T2 has the same configuration as that of the first connection terminal device T1, and the second connection terminal T21 connected to the reader / writer device 110 side and the data carrier 120 side via the rectifier circuit 123. And a second device side terminal T22 connected to the reference potential terminal E of the internal circuit 121. A clamp circuit 122 and a capacitor C1 are arranged in parallel with the internal circuit 121. The clamp circuit 122 limits the voltage applied to the internal circuit 121 to a predetermined voltage value.

The rectifier circuit 123 includes a first rectifier circuit 123a including diodes D1 to D2, a second rectifier circuit 123b including diodes D3 to D4, and a third rectifier circuit 123c including diodes D5 to D8. Converts incoming AC electrical signals to DC.
The diodes D6 and D8 connected to the reference potential terminal E of the internal circuit 121 in the tag in the third rectifier circuit 123c are used in common with the first to third rectifier circuits 123a to 123c.

  The first rectifier circuit 123a rectifies an alternating current flowing from the first connection terminal device T1 and the second connection terminal device T2 to the power supply input terminal A by the diodes D1 and D2 to generate a direct current voltage. Further, the second rectifier circuit 123b configured by the diodes D3 and D4 rectifies the signal current flowing from the first connection terminal device T1 and the second connection terminal device T2 to the signal input terminal B. The third rectifier circuit 123c rectifies a signal current flowing from the first connection terminal device T1 and the second connection terminal device T2 to the clamp circuit 122 to generate a DC voltage. Further, a capacitor C2 is provided between the signal input terminal B and the reference potential, and the amplitude of the data carrier signal input to the signal input terminal B is stabilized.

The first rectifier circuit 123a is connected to the internal circuit 121 after connecting a large-capacity C1 as a ripple filter to stabilize and supply the operating power of the internal circuit 121.
The second rectifier circuit 123b is for detecting the modulation and is connected to the signal input terminal B of the internal circuit 121 after connecting the capacitor C2 for bypassing the high frequency signal.
The third rectifier circuit 123c is supplied to the clamp circuit 122 and limits the voltage only when the rectified voltage exceeds a predetermined voltage, so that a capacitor that gives an operation delay is not connected.
As described above, by dividing the rectifier circuit into three, there is an advantage that a capacitor can be connected so as to have an optimum time constant for each purpose.

  In the present embodiment, by providing the rectifier circuit 123, when the reader / writer device 110 drives the data carrier 120 with a differential AC signal, the first connection terminal device T1, the second connection When a contact failure occurs in the terminal device T2 and the value of the contact resistance increases, for example, even when a contact resistance value increases due to foreign matter being caught, the terminal device T2 can be operated satisfactorily.

  This is because, when a foreign object is caught and the resistance value becomes large, the first connection terminal T11 and the first device side terminal in the first connection terminal device T1 (the same applies to the second connection terminal device T2). This is opposed to T12 with a gap corresponding to the height of the foreign matter, and a capacitance is created between the contact electrodes. Since a displacement current flows through this capacitance, it is possible to electrically secure a connection state. As a result, the data carrier 120 can be stably operated even when a contact failure occurs due to a high-resistance foreign object being caught.

In the present embodiment, the first connection terminal device T1 and the second connection terminal device T2 facing each other are formed in a planar shape having a predetermined area. For example, when a 5 mm square and an area of 25 mm ² have 30 μm of foreign matter between the terminals and the contact resistance increases to 1000 KΩ, the capacitance between the electrodes is about 7.5 pF, so the frequency is 10 MHz. Then, the impedance is 2120Ω. Therefore, even if the contact adheres with dirt and the contact resistance value increases, an advantage is obtained in that it can be driven through a capacitor connected in parallel.

  The reader / writer device 110 according to the present embodiment drives an AC drive signal output from the electrical signal generation circuit 111 by a signal output circuit 112 having an equivalently high output impedance. The signal output circuit 112 is configured by a parallel resonance circuit composed of L1 and C11, and differentially outputs the resonance voltage of the parallel resonance circuit to the first connection terminal device T1 and the second connection terminal device T2. Capacitors C12 and C13 are provided in series with the capacitor C11, and the impedance matching circuit 113 is configured by these capacitors C11, C12, and C13. In this example, the capacitor C11 serves both as a capacitor of the resonance circuit and a capacitor of the impedance matching circuit 113.

  When the parallel resonance voltage has a resonance frequency and Q is high, a voltage that is Q times the drive signal is obtained. For this reason, when the contact of the contacts T1 and T2 is poor and the contact resistance value is large, a large drive signal is obtained when the load impedance connected to the resonance circuit is large.

  On the other hand, when the contact between the contacts T1 and T2 is good, the load impedance of the resonance circuit becomes small, and the voltage at the resonance point decreases. Accordingly, when the contacts T1 and T2 are in good contact, excessive driving is not performed, and there is no inconvenience that an excessive voltage is applied to the data carrier 120. Therefore, even if a contact failure occurs in the contacts T1 and T2, the allowable range for driving the data carrier 120 can be widened.

  In this example, the parallel resonant circuit has a high impedance at the time of resonance, and a voltage Q times that of the drive signal source can be obtained. In addition, when a load is connected in parallel to the parallel resonance circuit, it is utilized that the resonance circuit falls from a high voltage when there is no load to a low voltage. Therefore, when the connection state with the data carrier 120 is incomplete, matching and resonance are combined to obtain the effects as described above.

That is, since the signal output circuit 112 of the reader / writer device 110 shown in FIG. 1 has a high output impedance, when the load impedance is large (when the contact is poor contact), the drive output becomes large and the data carrier 120 is driven. There is an advantage that it is difficult to run out.
On the other hand, since the output impedance is high, if the load impedance is small (when the contact is in normal contact), the drive output is small and there is an advantage that the data carrier 120 is not excessively driven. Thereby, according to the transmission system of the present embodiment, the first connection terminal device T1 and the second connection terminal device T2 can be connected in the conductor connection or the capacitor connection in the conductor connection or the capacitor connection in parallel. Become.

  FIG. 2 shows a modification of the impedance matching circuit 113, in which capacitors C12 and C13 for impedance matching are connected between a coil L1 and a capacitor C11 constituting a parallel resonance circuit.

FIG. 3 shows an example in which a resonance coil L2 that resonates with the signal frequency of the electric signal generation circuit 111 of the reader / writer device 110 is provided together with the equivalent input capacitance of the data carrier 120. By configuring in this way, the input impedance of the data carrier 120 can be increased, so that driving is facilitated, and there is an advantage that it is easy to drive even when the contact resistance is high or the capacitance between the electrodes is small.
When the magnetic flux from the coil L1 of the resonance circuit of the reader / writer device 110 is induced in the resonance coil L2 and a voltage is generated, the drive voltage via the first connection terminal device T1 and the second connection terminal device T2 Since interference occurs, it is desirable to change the directions of the coils L1 and L2 or keep them apart.

Next, a specific calculation example is shown.
(Calculation Example-1)
When driving of the data carrier 120 requires 9 Vpp or more and 1 mApp or more, when the power consumption of the data carrier 120 is 1.1 mW, the contact terminal is equivalently a parallel circuit of a contact resistance of 1000 K and an interelectrode capacitance of 7.5 pF. , This is two in series. For this reason, the drive circuit needs to be driven higher by the voltage drop in this portion, but the drive to be increased is about 13 Vpp. This level of driving is easy in this embodiment.

(Calculation Example-2)
If driving of the data carrier 120 requires 9 Vpp or more and 1 mApp or more, and the power consumption of the data carrier 120 is 1.1 mW, the contact terminal is equivalent to a contact resistance of 1000 KΩ and an interelectrode capacitance of 1 pF (impedance is 15 MHz at 10 MHz). 9KΩ) parallel circuit. Since there are two contact terminals, the drive circuit needs to be driven high in order to compensate for the voltage drop in this part, but the drive to be increased is 41 Vpp. The compensation driving amount corresponding to this voltage drop is in a range that can be easily realized when the Q of the tuning circuit of the driving circuit is 20 or more when the amplitude of the signal source is 5 Vpp.

In the present embodiment, the reader / writer device 110 and the data carrier 120 are electrically connected via the first connection terminal device T1 and the second connection terminal device T2. Therefore, in a state where the data carrier 120 is operating in response to the output of the parallel resonant circuit, the reader / writer device 110 and the data carrier 120 are one closed circuit when viewed from the outside, and the coil L1 The generated magnetic flux is not used for external driving.
Further, since the drive circuit has a differential output, the signal lines to the first and second connection terminal devices T1 and T2 are operating signals and are high-frequency signals of opposite phases, so that jumping to the surroundings can be suppressed.
Furthermore, jumping to the periphery can be suppressed by providing a guard ring connected to the ground potential around the shield wire and the first and second connection terminal devices T1 and T2.

  Furthermore, in order to prevent the magnetic flux from the coil L1 from leaking more reliably, it is desirable to use a coil using a closed magnetic circuit type core such as a toroidal core or a magnetic shield type coil. With this configuration, when the drive signal is weak, interference due to magnetic field coupling with the resonance coil L2 when the contact resistance values of the first connection terminal device T1 and the second connection terminal device T2 are large. The operation can be reduced.

  In each of the embodiments described above, it is also effective to dispose nanocarbon on the surface of the terminal in order to reduce the contact resistance of the contacts T1 and T2.

  The configuration for modulating the drive signal, the configuration in which the reader / writer device 110 receives a reply from the data carrier 120, and the configuration in which the reply from the data carrier 120 is returned can be configured using a known technique. In the embodiment described above, this is omitted.

110 Reader / Writer Device 111 Electric Signal Generation Circuit 112 Signal Output Circuit 113 Impedance Matching Circuit T1 First Connection Terminal Device T11 First Reader / Writer Terminal T12 First Data Carrier Terminal T2 Second Connection Terminal Device T21 Second Reader / writer terminal T22 second data carrier terminal L1 parallel resonant coil C11 parallel resonant capacitor C12, C12 matching capacitor 120 data carrier 121 internal circuit 122 clamp circuit 123 rectifier circuit 123a first rectifier circuit 123b second rectifier circuit 123c Third rectifier circuit

Claims (8)

An electronic device that operates by generating a DC voltage from electrical signals input from a first connection terminal and a second connection terminal arranged on the drive device side,
A first device-side terminal in contact with the first connection terminal;
A second device side terminal in contact with the second connection terminal;
An internal circuit connected between the first device side terminal and the second device side terminal, and a clamp circuit connected in parallel with the internal circuit and limiting a voltage applied to the internal circuit to a predetermined value When,
A rectifier circuit that converts an electrical signal input to the first device side terminal and the second device side terminal into a DC voltage;
The first device side terminal and the second device side terminal are configured in a planar shape having a predetermined area, and the first connection terminal, the first device side terminal, and the second connection terminal. And the second device-side terminal, the capacitance formed when the contact resistance is increased due to the gap between the conductor connection and the terminal and the high resistance foreign matter sandwiched or tilted, or deformed to open the gap. An electronic device characterized in that it is possible to connect a conductor connection or both of them in parallel among the capacitive connections.   The rectifier circuit includes a first rectifier circuit disposed between the first connection terminal and the second connection terminal and a power input terminal of the internal circuit, and the first connection terminal and the second connection terminal. A second rectifier circuit disposed between a connection terminal and a signal input terminal of the internal circuit; and a first rectifier circuit and a second connection terminal disposed between the clamp circuit and the first connection terminal. The electronic device according to claim 1, comprising:   3. The coil according to claim 1, wherein a coil that resonates in parallel with a frequency of a drive signal together with an equivalent input capacitance of the device is connected between the first connection terminal and the second connection terminal. Electronics. A driving device that outputs a high-frequency electrical signal via a first device-side terminal and a second device-side terminal disposed on the electronic device side,
A first connection terminal in contact with the first device side terminal;
A second connection terminal in contact with the second device side terminal;
A signal output circuit connected between the first connection terminal and the second connection terminal;
An electric signal generation circuit for outputting a high-frequency electric signal output from the first connection terminal and the second connection terminal to the signal output circuit;
A matching circuit disposed between the electrical signal generation circuit and the signal output circuit;
The signal output circuit and the matching circuit constitute a parallel resonance circuit, and the resonance voltage of the parallel resonance circuit changes according to a load impedance connected to the first connection terminal and the second connection terminal. A drive device characterized by being caused to.   The parallel resonant circuit has any contact between the first connection terminal and the first device side terminal and any contact between the second connection terminal and the second device side end. If the load impedance connected to the resonance circuit is bad and the resonance voltage of the parallel resonance circuit is high, the resonance voltage of the parallel resonance circuit is increased. If both contacts are good and the load impedance is low, the resonance voltage of the parallel resonance circuit is low. The drive device according to claim 4, wherein:   The first connection terminal and the second connection terminal are configured in a planar shape having a predetermined area, and the first device side terminal, the first connection terminal, and the second device side terminal 6. The driving device according to claim 4, wherein the second connection terminal can be connected in a conductor connection or a parallel connection of a conductor connection and a capacitor connection.   The drive device according to claim 4, wherein the signal output circuit outputs a high-frequency electrical signal in a differential manner.   A transmission system comprising the electronic device according to any one of claims 1 to 3 and the drive device according to any one of claims 4 to 7.

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