JP4671939B2 - Method for detecting internal signal of circuit and mounting board used therefor - Google Patents

Description

  The present invention relates to a method for detecting an internal signal of a circuit without contacting the circuit, and a mounting board used therefor.

As a conventional method for detecting an internal signal of a circuit without contacting the circuit, for example, as shown in FIG. 7A, a part of the wiring pattern L connected to the electronic component 3 is extended to transmit the antenna part. T is provided, and an electromagnetic wave emitted from the transmission antenna unit T is received as an electromagnetic wave W radiated from the electronic component 3 using a receiver R as shown in FIG. , See Patent Document 1.)
JP 7-27832 A

  However, the conventional method detects the electromagnetic waves W1 to W5 when there are a plurality of transmission antenna portions T and a plurality of electromagnetic waves W1 to W5 are emitted from the antenna portion T as shown in FIG. Therefore, as shown in the order of (1) to (3) according to the arrows in FIG. 8, it is necessary to move the receiver R to the vicinity of the specific circuit to be measured, and the detection procedure is complicated and efficient. There is a problem of being bad.

  Further, as shown in FIG. 9, the electronic circuit arranged in the control device has two control elements Ec (1) and Ec (2) represented by transistors, and changes the duty ratio of the drive signal. When driving and controlling the two solenoid valves Vs (1) and Vs (2), the basic frequencies of both control elements Ec (1) and Ec (2) are common. For this reason, in the above conventional method, the electromagnetic wave W1 emitted from the electronic circuit including the control element Ec (1) and the electromagnetic wave W2 emitted from the electronic circuit including the control element Ec (2) have basically the same frequency. It is impossible to judge whether electromagnetic waves are emitted from the electronic circuit.

  Furthermore, in the conventional method for measuring the electromagnetic wave radiated from the electronic circuit, as shown in FIG. 10, when another electronic device 300 is arranged around the electronic device 200 including the transmission antenna unit T, the transmission of the electronic device 200 is performed. There is a possibility that electromagnetic waves emitted from the antenna unit T adversely affect the operation of other electronic devices 300.

  The present invention has been made on the basis of such fact recognition, and can detect electromagnetic waves without taking a complicated procedure. Furthermore, when a plurality of the electromagnetic waves are detected, the identification is easy, and the surroundings can be detected. It is an object of the present invention to provide a method for detecting an internal signal of a circuit that does not affect the operation of the arranged circuit, and a mounting board used therefor.

  The present invention is a method for detecting an internal signal transmitted from each location in a circuit without contacting the circuit, and is provided in the vicinity of each location in the circuit where the internal signal is transmitted. Providing a resonance generating means comprising a resonance circuit for signal amplification and frequency selection and a transmitting antenna section connected thereto, and detecting an internal signal of the circuit by measuring an electromagnetic wave emitted from these resonance generation means It is a feature.

  The present invention provides an internal signal transmitted from each location in the circuit by measuring the frequency of each electromagnetic wave emitted from the resonance generating means by differentiating the frequency of the electromagnetic waves emitted from the resonance generating means. Is preferably detected.

  In the present invention, it is preferable that one of the front and back surfaces of the circuit is shielded to regulate the direction of electromagnetic waves emitted from the resonance generating means.

  In the present invention, it is preferable that the resonance frequency of the resonance circuit in the resonance generating means is set to a frequency different from the harmonic component of the operation frequency of the circuit.

  In the present invention, when the circuit has a control element for driving and controlling the actuator, it is preferable to measure the electromagnetic wave by providing the resonance generating means with a space near the input side of the control element.

  In order to realize such a detection method, a signal is amplified by mounting a circuit board on a printed circuit board, with an interval in the vicinity of the printed circuit board where an internal signal of the circuit is emitted. A mounting board comprising a resonance circuit for selecting a frequency and at least one resonance generating means including a transmission antenna unit connected to the resonance circuit is preferable.

  According to the present invention, since the resonance frequency of the resonance circuit can be changed in the resonance generating means, if the frequency of the electromagnetic wave measured by one receiver is analyzed, a plurality of such circuits are detected in detecting the internal signal of the circuit. Even if it exists in a location, it is not necessary to take complicated procedures, such as moving a receiver. In addition, even when the electromagnetic waves are detected simultaneously from a plurality of locations, the frequency components differ depending on the resonance circuit, so that the identification can be easily performed. That is, according to the present invention, if the measurement of electromagnetic waves is performed only once by one receiver, it is possible to detect the presence / absence of internal signals in all the circuits provided with the resonance generating means in the vicinity.

  Further, the resonance generating means according to the present invention is not electrically connected to the circuit because it is provided in the vicinity of the circuit to be measured with a space therebetween. For this reason, according to the present invention, even if the electromagnetic wave emitted from the transmission antenna unit of the resonance generating unit becomes noise or, conversely, even if external noise is received by the transmission antenna unit, Almost no electrical influence from resonance generating means. That is, according to the present invention, the operation of the circuit is hardly affected.

  In the present invention, if one of the front and back surfaces of the circuit is shielded to restrict the direction of the electromagnetic wave emitted from the resonance generating means, the influence of the electromagnetic wave on the periphery of the circuit can be reduced.

  Furthermore, in the present invention, when the resonance frequency of the resonance circuit in the resonance generating means is set to a frequency different from the harmonic component of the operating frequency of the circuit, the resonance circuit of the resonance generating means is used for detecting an internal signal. Resonates and emits electromagnetic waves from the transmitting antenna unit. However, while the circuit is operated normally, the resonance circuit of the resonance generating means does not resonate and unnecessary electromagnetic waves are not emitted from the transmitting antenna unit. That is, according to the present invention, an internal signal can be detected without affecting the original operation of the circuit.

  Furthermore, according to the mounting board of the present invention, the effects of the detection method described above can be realized easily and inexpensively using an existing receiver or frequency analysis device.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a plan view showing an example of a mounting board used in the detection method of the present invention, and FIG. 2 is an enlarged view showing a resonance generating means according to the present invention provided on the mounting board of FIG.

  In FIG. 1, reference numeral 1 denotes a mounting board in which a surface mounting component 3 represented by an IC (integrated circuit), a resistor, a transistor, and the like is mounted on a surface 2 a of a printed board 2. In the mounting substrate 1, two circuits R1 and R2 are formed on the surface 2a of the printed circuit board 2.

  The first circuit R1 has an input terminal 4a, the input terminal 4a is connected to the surface-mounted component 3a by the wiring pattern 5a, and the surface-mounted component 3a is connected to the surface-mounted component 3b by the wiring pattern 5b. Similarly, the second circuit R2 has an input terminal 4b, and this input terminal 4b is connected to the surface mount component 3c by the wiring pattern 5c, and the surface mount component 3c is connected to the surface mount component 3b by the wiring pattern 5d. .

  In FIG. 2, reference numeral 10 denotes resonance generating means provided on the printed board 2 independently of the circuits R1 and R2. The resonance generating means 10 includes a resonance circuit 11 for signal amplification and frequency selection. The resonance circuit 11 has a coil pattern 11a and a capacitor pattern 11b which are printed on the surface 2a of the printed board 2 and connected in parallel, and one of them is connected to the transmission antenna unit 12.

  The transmission antenna unit 12 transmits an electromagnetic wave W having a frequency corresponding to the resonance frequency fo of the resonance circuit 11. That is, the frequency f of the electromagnetic wave W emitted from the transmitting antenna unit 12 can be changed as appropriate by changing the resonance frequency fo of the resonance circuit 11. The resonance frequency fo of the resonance circuit 11 can be changed as appropriate by changing the shape (number of turns) of the coil pattern 11a and the shape (land area) of the capacitor pattern 11b.

In FIG. 1, the resonance generating means 10 for detecting the internal signal of the first circuit R1 is denoted by reference numeral 10A. The resonance generating means 10A is provided on the surface 2a of the printed circuit board 2 at a distance in the vicinity of the first circuit R1, and has an independent circuit configuration that is not electrically connected to the first circuit R1. Thereby, when an electric signal flows as an internal signal of the first circuit R1, the resonance circuit 11 (A) of the resonance generating means 10A resonates under the influence of the electric signal and is connected to the resonance circuit 11 (A). from part 12A transmits an electromagnetic wave W _a having a frequency corresponding to the resonant frequency fo (a).

In FIG. 1, the resonance generating means 10 for detecting the internal signal of the second circuit R2 is denoted by reference numeral 10B. The resonance generating means 10B is also provided on the printed circuit board 2 in the vicinity of the second circuit R2, with an interval, and has an independent circuit configuration that is not electrically connected to the second circuit R2. Thus, when an electric signal flows as an internal signal of the second circuit R2, the resonance circuit 11 (B) of the resonance generating means 10B also resonates due to the influence of the electric signal and is connected to the resonance circuit 11 (B). transmitting the electromagnetic wave W _B having a frequency corresponding to the resonant frequency fo (B) from part 12B.

  That is, the mounting substrate 1 is a mounting substrate in which a plurality of circuits are formed on the printed circuit board 2, and internal signals of the first circuit R1 and the second circuit R2 among the entire circuits on the printed circuit board 2 are generated. Two resonance generating means 10A and 10B comprising resonance circuits 11 (A) and 11 (B) for signal amplification and frequency selection and transmission antenna portions 12A and 12B connected to the resonance circuits 11 (A) and 11 (B) for signal amplification and frequency selection are provided in the vicinity of each location Is.

In Figure 1, reference numeral 20 is a resonance producing means 10A, 10B of the transmitting antenna section 12A, the electromagnetic wave W _A, a receiver for receiving W _B emitted from 12B (receiving antenna). Receiving antenna 20, the resonance generating means 10A, receives two waves W _A emitted from 10B, the W _B simultaneously, the composite waveform is chronologically measured as shown in FIG. 3 (a).

And the frequency f _A of the electromagnetic wave W _A emitted from the resonance generating unit 10A, and the frequency f _B of the electromagnetic wave W _B emitted from the resonance generating unit 10B, as described above, each of the resonant circuits 11a (A), 11a (B ) Resonance frequencies fo (A) and fo (B). For this reason, if the frequencies f _A and f _B included in the measured waveform are analyzed by, for example, a spectrum analyzer using Fourier transform, the resonance is generated from the resonance generating means 10A as shown in FIG. The frequency f _{A of} the electromagnetic wave and the frequency f _{B of} the electromagnetic wave emitted from the resonance generating means 10B can be extracted.

Incidentally, in FIG. 3 (b), the frequency f _A of the electromagnetic wave W _A that are expected from the resonance generating unit 10A is measured, but the frequency f _B of the electromagnetic wave W _B to be emitted from the resonance generating unit 10B is being measured Absent. In this case, the internal signal of the first circuit R1 can be detected, but the internal signal of the second circuit R2 cannot be detected. Thus, it can be seen that the first circuit R1 functions normally, but the second circuit R2 does not function normally for some reason.

Further, when the first circuit R1 and the second circuit R2 have the same operating frequency (clock frequency), the resonance frequency fo (A of one of the resonance circuits 11 (A) or 11 (B) of these circuits R1 and R2 ) Or fo (B) is twice the resonance frequency fo (B) or fo (A) of the other resonance circuit 11 (B) or 11 (A), the frequency f of the electromagnetic wave emitted from the resonance generating means 10A _A and the frequency f _{B of the} electromagnetic wave emitted from the resonance generating means 10B can be changed.

According to such a detection method using the resonance generating means 10, the resonance frequency fo of the resonance circuit 11 of the resonance generating means 10 can be changed, so that the frequencies f of the electromagnetic waves W _A and W _B measured by one receiving antenna 20 are obtained. _{If A} and f _B are analyzed, in detecting the internal signal of the circuit, even if the circuit is located at a plurality of locations such as the first circuit R1 and the second circuit R2, the complicated operation such as moving the receiving antenna 20 is required. There is no need to follow the steps. Moreover, even when the electromagnetic waves W _A and W _B are detected simultaneously from a plurality of locations of the first circuit R1 and the second circuit R2, the frequency components f _A and f _B are generated in the resonance circuits 11 (A) and 11 (B). Since it differs depending on each, it can be easily identified. That is, according to the detection method using the resonance generating unit 10, the electromagnetic wave W _A, W be performed only once in one receive antenna 20 to measure the _B, circuit all internal signal having a resonance producing means 10 in the vicinity The presence or absence of can be detected.

  Further, since the resonance generating means 10 is provided in the vicinity of the first circuit R1 and the second circuit R2 to be measured with a space therebetween, it is electrically connected to the first circuit R1 and the second circuit R2. Absent. For this reason, even if the electromagnetic wave W emitted from the transmission antenna unit 12 of the resonance generating means 10 becomes noise or, conversely, external noise is received by the transmission antenna unit 12, the first circuit R1 and the second circuit to be measured The two circuits R2 are hardly affected electrically from the resonance generating means 10. That is, according to the method using the resonance generating means 10, the operations of the first circuit R1 and the second circuit R2 are hardly affected.

  Furthermore, according to the mounting substrate 1, the effects of the detection method described above can be realized easily and inexpensively using an existing frequency analysis device typified by the existing receiving antenna 20 and spectrum analyzer.

Meanwhile, according to the detection method is a present invention, the first circuit R1 and the second circuit while a shield to resonance producing means 10A of the front and rear surfaces of the R2, the electromagnetic wave W _A emitted from 10B, for regulating the direction of W _B It is preferable.

  FIG. 4 is a schematic side view showing an example of the mounting substrate 1 that is used in the detection method according to the present invention and adopts the shield technique described above. In addition, in the following description, the same part as FIGS. 1-3 has the same code | symbol, and abbreviate | omits the description.

  In the mounting substrate 1 shown in FIG. 4, a shield pattern 6 is formed on the back surface 2 b of the printed circuit board 2. The shield pattern 6 has a function of blocking the electromagnetic wave W, and is formed by laminating conductors such as copper foil by printing. As a result, the electromagnetic wave W emitted from the resonance generating means 10 is radiated only from the front surface 2a of the printed circuit board 2 as indicated by reference numeral A, and the electromagnetic wave W from the back surface 2b of the printed circuit board 2 is expressed by reference numeral B. , Is blocked by the shield pattern 6.

That is, the direction of the electromagnetic wave W emitted from the resonance generating means 10 is restricted only to the direction radiated from the surface 2a of the printed board 2. Thus, resonance producing means 10A to the rear surface of the first circuit R1 and the second circuit R2 shielded, electromagnetic waves W _A emitted from 10B, if regulated to the direction of W _B, first circuit R1 and the like noises The influence of the electromagnetic waves W _A and W _{B on} the periphery of the two-circuit R2 can be suppressed small.

  By the way, while the first circuit R1 and the second circuit R2 are operating normally, their processing is synchronized at the operating frequency fc. Therefore, the resonance frequency fo (A) of the resonance circuit 11 (A) in the resonance generating means 10A and the resonance frequency fo (B) of the resonance circuit 11 (B) in the resonance generating means 10b are the first circuit R1 and the first circuit R1. It is preferable to set a frequency different from the harmonic component of the operating frequency fc of the two-circuit R2.

  According to such a setting, in the test mode for the purpose of detecting the internal signal, as shown in FIG. 5A, the resonance circuits 11 (A) and 11 (B) resonate to transmit antenna units 12A and 12B. In the normal circuit operation for the purpose of fulfilling the original functions of the first circuit R1 and the second circuit R2, as shown in FIG. 5B, the resonance circuits 11 (A), 11 are emitted. (B) does not resonate and unnecessary electromagnetic waves are not emitted from the transmitting antenna portions 12A and 12B. That is, according to such setting, it is possible to detect the presence or absence of internal signals of the first circuit R1 and the second circuit R2 without affecting the original operation of the first circuit R1 and the second circuit R2.

  FIG. 6 is a schematic plan view showing a control device 100 for an automatic transmission used in the detection method according to the present invention and two solenoid valves 160a and 160b that are driven and controlled by the control device 100. FIG. In FIG. 6, the same parts as those in FIGS.

  The control device 100 is connected to the CPU (central processing unit) 120 and the CPU 120 on the printed circuit board 110, and outputs a drive signal with duty control to the solenoid valves 160a and 160b. It has two control elements 130a and 130b that actually control the drive. Solenoid valves 160a and 160b are connected to the two control elements 130a and 130b by harnesses 140a and 140b, respectively.

  In FIG. 6, the resonance generating means 10A is provided in the vicinity of the input side of the control element 130a, for example, in the vicinity of the wiring pattern 150a connecting the CPU 120 and the control element 130a with a space therebetween, that is, in the vicinity of the input side of the control element 130b. For example, the resonance generating means 10B is provided in the vicinity of the wiring pattern 150b that connects the CPU 120 and the control element 130b with a space therebetween.

Thus, the solenoid valve 160a, if you that there is an abnormality in the 160 b, the resonance generating unit 10A, the electromagnetic wave W _A from 10B, the W _B is measured, if there is an abnormality in the electromagnetic wave W _A, W _B, the output of the CPU120 or control elements 130a, 130b input, i.e., while it is possible to estimate that there is an abnormality CPU120 or the wiring patterns 150a, to 150b, the electromagnetic wave W _a, when there is no abnormality in the W _B, the control device 130a, since 130b, i.e., It can be estimated that the control elements 130a and 130b, the harnesses 140a and 140b, or the solenoid valves 160a and 160b themselves are abnormal.

  Although the above is a preferred example of the present invention, various modifications can be made by those skilled in the art within the scope of the claims. For example, the direction of the transmission antenna unit of the resonance generating unit can be changed as appropriate.

  The present invention can be applied to all techniques for inspecting whether or not an internal signal is abnormal in an electronic circuit.

It is a schematic plan view which illustrates the mounting substrate used for the detection method which is this invention. It is an enlarged view which shows the resonance generation means based on this invention provided in the mounting board | substrate of FIG. (a), (b) is explanatory drawing regarding the frequency analysis of the electromagnetic waves emitted from each resonance generation means of FIG. 1, respectively. It is a model side view which shows an example of the mounting substrate which was used for the detection method which is this invention, and employ | adopted the electromagnetic wave shielding technique. (a), (b) is a schematic plan view showing the operating state of the resonance generating means when the resonance frequency of the resonance circuit in the resonance generating means is set to a frequency different from the harmonic component of the operating frequency of the circuit. . It is a schematic plan view which shows the control apparatus of the automatic transmission used for the detection method which is this invention, and two solenoid valves drive-controlled by this control apparatus. (a), (b) is a schematic enlarged view illustrating a conventional transmission antenna unit that radiates electromagnetic waves from an electronic component, respectively, and a schematic diagram illustrating a state in which an electromagnetic wave emitted from the transmission antenna unit is received by a receiver It is sectional drawing. It is a schematic cross section which illustrates the conventional receiving procedure. It is a schematic plan view for explaining the characteristics of electromagnetic waves emitted from the drive control element of the actuator of the electronic circuit arranged in the drive control device of the actuator. It is a schematic cross section for demonstrating the influence by the electromagnetic waves emitted from the transmission antenna part when other electronic devices are arrange | positioned around the conventional electronic device containing a transmission antenna part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mounting board 2 Printed circuit board 3 Surface mount component (electronic component)
4 Input terminal 5 Wiring pattern 6 Electromagnetic wave shield pattern
10 Resonance generation means
11 Resonant circuit
11a Coil pattern
11b Capacitor pattern
12 Transmitting antenna
20 Receiving antenna (receiver)
R1 first circuit R2 second circuit

Claims (6)

A method for detecting an internal signal transmitted from each location in a circuit without contacting the circuit,
Resonance generating means consisting of a resonance circuit for signal amplification and frequency selection and a transmitting antenna unit connected to the resonance circuit is provided in the vicinity of each part of the circuit where the internal signal is transmitted. A method for detecting an internal signal of a circuit, wherein the internal signal of the circuit is detected by measuring an electromagnetic wave emitted.   Detecting an internal signal transmitted from each location in the circuit by measuring the frequency of each electromagnetic wave emitted from the resonance generating means with different frequencies of the electromagnetic waves emitted from the resonance generating means. A method for detecting an internal signal of a circuit according to claim 1.   The method for detecting an internal signal of a circuit according to claim 1 or 2, wherein one of the front and back surfaces of the circuit is shielded to regulate the direction of electromagnetic waves emitted from the resonance generating means.   The method for detecting an internal signal of a circuit according to claim 1 or 2, wherein the resonance frequency of the resonance circuit in the resonance generating means is set to a frequency different from a harmonic component of the operating frequency of the circuit. .   5. The electromagnetic wave measurement according to claim 1, wherein when the circuit has a control element for driving and controlling an actuator, the electromagnetic wave is measured by providing the resonance generating means at an interval near the input side of the control element. A method for detecting an internal signal of a circuit according to claim 1. A mounting board in which a circuit is formed on a printed board,
There is provided at least one resonance generating means including a resonance circuit for signal amplification and frequency selection and a transmission antenna unit connected thereto, with an interval in the vicinity of a place on the printed circuit board where an internal signal of the circuit is emitted. Mounting board characterized by

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