Immunity performance evaluation probe
The immunity performance evaluation probe addresses the inaccuracy of existing noise testing apparatuses by using a resonating and decoupling mechanism to ensure precise evaluations of electronic components' immunity performance even with sinusoidal AC signals.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- MITSUBISHI ELECTRIC CORP
- Filing Date
- 2025-03-10
- Publication Date
- 2026-06-04
AI Technical Summary
Existing noise testing apparatuses fail to accurately evaluate the immunity performance of electronic components like LSIs or ICs when using sinusoidal AC signals that swing to negative amplitudes, leading to inaccurate evaluations.
The immunity performance evaluation probe employs a test signal application probe body with a signal coupling element and a stub body, both equipped with adjusters, to resonate and decouple test signals, ensuring accurate evaluation even with sinusoidal AC signals.
Enables highly accurate immunity performance evaluations of electronic components by resonating and decoupling test signals, preventing interference and ensuring reliable evaluations.
Smart Images
Figure JP2025008646_04062026_PF_FP_ABST
Abstract
Description
Probe for evaluating immunity performance
[0001] This disclosure relates to an immunity performance evaluation probe used to evaluate the electromagnetic noise immunity performance of electronic components such as LSIs or ICs mounted on a printed circuit board.
[0002] With the increasing sophistication of electronic devices in recent years, the scale of electronic components such as LSIs or ICs used in electronic devices, and the number of electronic components mounted, have also increased. Since these electronic components greatly affect the performance of the device, quality control is crucial. In particular, the immunity performance of LSIs or ICs—the degree to which they can withstand noise—is an indispensable element in guaranteeing the reliability of the device. Against this backdrop, international standards, such as the IEC 62132 series and IEC 62215 series, have established methods for evaluating the response of LSIs or ICs by applying a signal of a specified level that simulates noise.
[0003] Patent Document 1 describes a noise testing apparatus that uses an IC mounted on a printed circuit board as the device under test (DUT). The noise testing apparatus described in Patent Document 1 comprises a pulse generator 10, a pattern generator 20, a malfunction detection means, a first overvoltage protection circuit, and a second overvoltage protection circuit.
[0004] The pulse generator 10 is a noise source that applies pulse noise to the IC terminals of the device under test (DUT) by electrically contacting them with a contact probe, thereby causing malfunctions in the normal circuit operation of the DUT. The pattern generator 20 generates multiple test signals to set the DUT to a predetermined operating state and applies a test pattern to the DUT input terminal. It also generates multiple expected value patterns to determine whether the DUT output signal output from the DUT output terminal is under normal output conditions and supplies these to the malfunction detection means.
[0005] The malfunction detection circuit receives multiple DUT output signals from the DUT and the expected value pattern output from the pattern generator 20, compares the two for agreement, and outputs a malfunction signal if a mismatch is detected. The first overvoltage protection circuit protects the output terminal of the pattern generator 20 from pulse noise applied to the DUT. The second overvoltage protection circuit protects the input terminal of the malfunction detection means from pulse noise applied to the DUT. The first and second overvoltage protection circuits each include a series resistor, a clamp diode, a positive power supply, a negative power supply, and a bypass capacitor.
[0006] Japanese Patent Publication No. 2004-309153
[0007] Since the noise test apparatus shown in Patent Document 1 is configured as described above, the first overvoltage protection circuit and the second overvoltage protection circuit only operate when the noise voltage exceeds the clamp voltage of the clamp diode. Therefore, when a sinusoidal AC signal that also swings to a negative amplitude is used as the noise signal, the noise signal leaks back to the pattern generator 20, resulting in the problem that accurate evaluation of immunity performance is not possible.
[0008] This disclosure has been made in view of the above-mentioned points, and aims to provide an immunity performance evaluation probe that can accurately evaluate the immunity performance of electronic components mounted on a printed circuit board, even if the test signal for evaluating immunity performance is a sinusoidal AC signal that also swings to negative amplitudes.
[0009] The immunity performance evaluation probe according to this disclosure comprises a test signal application probe body having a test signal application contact that contacts and electrically connects to wiring for electronic components connected to power or signal IC terminals of electronic components mounted on a printed circuit board, and a signal coupling element, which applies a test signal from the test signal application contact to the wiring for electronic components via the signal coupling element; a stub body having a stub contact that contacts and electrically connects to the wiring for electronic components, a terminal, a stub coupling element interposed between the stub contact and the terminal, and an adjuster for adjusting the position of the terminal so that the length from the stub contact to the terminal is the length at which the test signal resonates; and an adjuster for adjusting the distance between the test signal application contact and the stub contact.
[0010] According to this disclosure, it is possible to perform highly accurate immunity performance evaluations on electronic components mounted on printed circuit boards.
[0011] This is a perspective view showing the immunity performance evaluation probe according to Embodiment 1. This is a perspective view showing the probe body for applying the test signal of the immunity performance evaluation probe according to Embodiment 1. This is a perspective view showing the stub body of the immunity performance evaluation probe according to Embodiment 1. This is a perspective view showing the clip on the stub body of the immunity performance evaluation probe according to Embodiment 1. This is a perspective view showing the adjuster on the stub body of the immunity performance evaluation probe according to Embodiment 1. This is a perspective view showing the adjustment device of the immunity performance evaluation probe according to Embodiment 1. This is a perspective view showing the usage state of the immunity performance evaluation probe according to Embodiment 1.
[0012] Embodiment 1. An immunity performance evaluation probe according to Embodiment 1 will be described with reference to Figures 1 to 7. The immunity performance evaluation probe according to Embodiment 1 is an immunity performance evaluation probe used to evaluate the electromagnetic noise immunity (immunity) performance of electronic components such as LSIs or ICs mounted on a printed circuit board. The electronic component is the device under test, and is hereinafter referred to as DUT. The printed circuit board on which the DUT is mounted is the test board.
[0013] The DUT has numerous lead terminals or ball-shaped external terminals. These lead terminals or ball-shaped external terminals are collectively referred to as IC terminals below. IC terminals include signal terminals, power terminals, and ground terminals. In the following explanation, to avoid complexity, power terminals will also be referred to simply as signal terminals. Similarly, ground terminals will be referred to as ground terminals.
[0014] Wiring that is electrically connected to signal terminals and formed on the surface of a printed circuit board is called electronic component wiring. In other words, electronic component wiring is a term that includes both signal wiring and power supply wiring. Wiring that is electrically connected to ground terminals and formed on the surface of a printed circuit board is called ground wiring.
[0015] The immunity performance evaluation probe according to Embodiment 1 comprises a test signal application probe body 100 (hereinafter simply referred to as the probe body 100), a stub body 200, and a pair of adjusters 300A and 300B, as shown in Figure 1. Since the pair of adjusters 300A and 300B have the same configuration, to avoid complexity, they will be described as adjuster 300 unless it is necessary to explain them separately. In Embodiment 1, a pair of adjusters 300A and 300B are used, but there may be one adjuster 300, or three or more adjusters 300.
[0016] The probe body 100 has a test signal application contact 101 (hereinafter simply referred to as the application contact 101) that contacts and electrically connects to the wiring for electronic components, and a signal coupling element 102, and applies the test signal from the application contact 101 to the wiring for electronic components via the signal coupling element 102. The test signal is output from a signal generator. The test signal is a signal of a specified level that simulates noise according to the international standards IEC 62132 series or IEC 62215 series. The test signal is a pulsed noise signal consisting of high frequencies or a sinusoidal AC noise signal consisting of high frequencies.
[0017] As shown in Figures 1 and 2, the probe body 100 comprises a probe body substrate 10, an application contact 101, a signal coupling element 102, a first signal wiring 103, a second signal wiring 104, a first ground contact 111, a first ground wiring 112, a second ground contact 121, a second ground wiring 122, and a connector 130. The probe body 100 is constructed from a printed circuit board.
[0018] In Embodiment 1, the system includes a first ground contact 111 and a first ground wiring 112, and a second ground contact 121 and a second ground wiring 122. However, the system may also consist of only the first ground contact 111 and the first ground wiring 112.
[0019] The probe substrate 10 (hereinafter simply referred to as substrate 10) is a rectangular dielectric insulating substrate having a pair of end sides 10a, 10b and a pair of side sides 10c, 10d. The application contact 101 is mounted in the center of one of the pair of end sides 10a, 10b of the substrate 10. The application contact 101 has a tapered tip, and the tip contacts the wiring for the electronic component to make an electrical connection.
[0020] The signal coupling element 102 is mounted on the surface of the substrate 10 and is a capacitor in which one electrode is arranged on one end side 10a and the other electrode is arranged on the other end side 10b of the pair of end sides 10a and 10b. The capacitance of the signal coupling element 102 is such that it exhibits a low impedance to the test signal and a high impedance to the signal flowing through the wiring for the electronic components. In other words, the signal coupling element 102 allows the test signal to pass through and blocks the signal flowing through the wiring for the electronic components.
[0021] The first signal wiring 103 has one end electrically connected to the application contact 101 and the other end electrically connected to one electrode of the signal coupling element 102. The first signal wiring 103 is formed in a straight line on the surface of the substrate 10, extending parallel to the side edges 10c and 10d from the center of one end edge 10a to the other end edge 10b, to the position of one electrode of the signal coupling element 102.
[0022] One end of the second signal wiring 104 is electrically connected to the other electrode of the signal coupling element 102, and a test signal is applied to the other end. The second signal wiring 104 is formed in a straight line on the surface of the substrate 10, extending parallel to the side edge 10b from the position of the other electrode of the signal coupling element 102 to the center of the other end edge 10b.
[0023] The first ground contact 111 is mounted on one of the pair of side edges 10c and 10d on one end edge 10a of the substrate 10. The first ground contact 111 has a tapered tip, and the tip contacts the ground wiring on the substrate under test to make an electrical connection and bring it to ground potential.
[0024] In the first embodiment, the ground wiring also includes wiring connected to a reference potential on the test substrate. The first ground wiring 112 is formed along one side 10c of the substrate 10, extending from one end 10a to the other end 10b, and one end is electrically connected to the first ground contact 111.
[0025] The second ground contact 121 is mounted on the other side 10d of a pair of side edges 10c and 10d on one end edge 10a of the substrate 10. The second ground contact 121 has a tapered tip, and its tip contacts the ground wiring on the substrate under test to make an electrical connection and bring it to ground potential. The second ground wiring 122 is formed along the other side 10d of the substrate 10, extending from one end edge 10a to the other end edge 10b, and one end is electrically connected to the second ground contact 121.
[0026] The connector 130 is mounted in the center of the other end 10b of the circuit board 10. The connector 130 has a core wire 131 and an outer conductor 132. The outer conductor 132 also includes a so-called housing. The core wire 131 of the connector 130 is electrically connected to the other end of the second signal wiring 104. The core wire 131 of the connector 130 is electrically connected to the core wire of the cable, and a test signal from the signal generator is applied via the core wire of the cable.
[0027] The outer conductor 132 of the connector 130 is electrically connected to the other end of the first ground wire 112 and the other end of the second ground wire 122, respectively. The outer conductor 132 of the connector 130 is electrically connected to the cable shield.
[0028] As shown in Figures 1 and 3, the stub body 200 includes a stub contact 201 that contacts and electrically connects to the wiring for electronic components, a terminal 230, a stub coupling element 202 interposed between the stub contact 201 and the terminal 230, and an adjuster 240 for adjusting the position of the terminal 230 so that the length from the stub contact 201 to the terminal 230 is the length at which the test signal resonates.
[0029] Now, if we consider the wavelength of the test signal applied from the core wire 131 of the connector 130 to the wiring for the electronic component via the second signal wiring 104, signal coupling element 102, first signal wiring 103, and application contact 101 in the test signal application probe body 100 to be λ, then the length L from the stub contact 201 to the terminal 230 is... １ The terminal 230 is moved using the adjuster 240 so that the wavelength is a natural number multiple of half the wavelength λ [(λ / 2) × n] (where n is a natural number). The figure shows the case where n is 1.
[0030] As shown in Figure 3, the stub body 200 comprises a substrate 20 for the stub body, a stub contact 201, a stub coupling element 202, a first stub wiring 203, a second stub wiring 204, a first ground contact 211, a first ground connection line 212, a second ground contact 221, a second ground connection line 222, a terminal 230, and an adjuster 240. The stub body 200 is constructed from a printed circuit board.
[0031] In Embodiment 1, the system includes a first ground contact 211 and a first ground connection wire 212, and a second ground contact 221 and a second ground connection wire 222. However, the system may also consist only of the first ground contact 211 and the first ground connection wire 212.
[0032] The stub substrate 20 is a rectangular dielectric insulating substrate having a pair of end sides 20a, 20b and a pair of side sides 20c, 20d. The stub substrate 20 is made of the same material as the substrate 10. The stub contact 201 is mounted on the central part of one of the pair of end sides 20a, 20b of the stub substrate 20.
[0033] The stub contact 201 has a tapered tip, and the tip contacts the wiring for the electronic component to make an electrical connection. When evaluating immunity performance, the electrical contact position of the stub contact 201 with the wiring for the electronic component is located further away from the DUT than the electrical contact position of the application contact 101 with the wiring for the electronic component, and closer to a circuit other than the DUT to which the wiring for the electronic component is connected.
[0034] The stub coupling element 202 is mounted on the surface of the substrate 20 and is a capacitor in which one electrode is arranged on one end side 20a and the other electrode is arranged on the other end side 20b of the pair of end sides 20a and 20b. The capacitance of the stub coupling element 202 is such that it exhibits a low impedance to the test signal and a high impedance to the signal flowing through the wiring for the electronic component. In other words, the stub coupling element 202 allows the test signal to pass through but blocks the signal flowing through the wiring for the electronic component.
[0035] The first stub wiring 203 has one end electrically connected to the stub contact 201 and the other end electrically connected to one electrode of the stub coupling element 202. The first stub wiring 203 is formed in a straight line on the surface of the stub substrate 20, extending parallel to the side edges 20c and 20d from the center of one end edge 20a to the other end edge 20b, to the position of one electrode of the stub coupling element 202.
[0036] The second stub wiring 204 has one end electrically connected to the other electrode of the stub coupling element 202. On the surface of the substrate 20, the second stub wiring 204 is formed in a straight line, extending parallel to the side edge 20b from the position of the other electrode of the stub coupling element 202 to the center of the other end edge 20b.
[0037] The first ground contact 211 is mounted on one side 20c of the pair of side edges 20c and 20d of one end edge 20a of the stub body substrate 20. The first ground contact 211 has a tapered tip, and the tip contacts the ground wiring on the test target substrate and is electrically connected thereto, and is set to the ground potential. The first ground connection line 212 is formed to extend from one end edge 20a portion to the other end edge 20b portion along one side 20c of the stub body substrate 20, and one end portion is electrically connected to the first ground contact 211.
[0038] The second ground contact 221 is mounted on the other side 20d of the pair of side edges 20c and 20d of one end edge 20a of the stub body substrate 20. The second ground contact 221 has a tapered tip, and the tip contacts the ground wiring on the test target substrate and is electrically connected thereto, and is set to the ground potential. The second ground connection line 222 is formed to extend from one end edge 20a portion to the other end edge 20b portion along the other side 20d of the substrate 20, and one end portion is electrically connected to the second ground contact 221.
[0039] The terminal 230 is in electrical contact (electrical connection) with the other end of the second stub wiring 204, the other end of the first ground connection line 212, and the other end of the second ground connection line 222, and sets the potential of the other end of the second stub wiring 204 to the ground potential. The terminal 230 has a short - circuit terminal 231 and a pair of clips 232.
[0040] The short - circuit terminal 231 is a flat - plate - shaped conductive plate having rigidity and is arranged with its surface facing the surface of the stub body substrate 20. The surface of the short - circuit terminal 231 is rectangular. The short - circuit terminal 231 is arranged with its longitudinal direction parallel to the other end edge 20b of the stub body substrate 20 at the other end edge 20b portion of the stub body substrate 20.
[0041] The length of one short-circuit termination terminal 231 is the same as the width of the stub substrate 20, that is, the distance between one side 20c and the other side 20d. In the short-circuit termination terminal 231, the central surface is in electrical contact with the surface of the other end of the second stub wiring 204, the surface at one end is in electrical contact with the surface of the other end of the first ground connection line 212, and the surface at the other end is in electrical contact with the other end of the second ground connection line 214.
[0042] The pair of clips 232 have their short-circuit termination terminals 231 facing the other end 20b of the stub substrate 20. Each of the pair of clips 232 is made of a material such as a conductor that is easily elastically deformable, processed into a plate shape, and bent so that both sides face each other.
[0043] In other words, each pair of clips 232, as shown in Figure 4, has a body 232a consisting of a base and a pair of legs extending from both sides of the base, and a pair of fixing contact portions 232b extending from each of the pair of legs. The inner surfaces of the pair of fixing contact portions 232b are parallel to each other. In each pair of clips 232, the pair of legs on the body 232a generate an elastic force inward.
[0044] As shown in Figure 4, one of the pair of clips 232 has a fixing contact portion 232b that contacts the back surface of the stub body substrate 20, and the other fixing contact portion 232b contacts the back surface of one end of the short-circuit terminal 231, and the inward elastic force of the pair of legs of the main body 232a presses the surface of one end of the short-circuit terminal 231 against the surface of the other end of the first ground connection wire 212, thereby attaching one end of the short-circuit terminal 231 to the stub body substrate 20.
[0045] As shown in Figure 4, one of the pair of clips 232 has a fixing contact portion 232b that contacts the back surface of the stub body substrate 20, and the other fixing contact portion 232b contacts the back surface of the other end of the short-circuit terminal 231, and the inward elastic force of the pair of legs of the main body 232a presses the surface of the other end of the short-circuit terminal 231 against the surface of the other end of the second ground connection wire 214, thereby attaching the other end of the short-circuit terminal 231 to the stub body substrate 20.
[0046] Since one end and the other end of the short-circuit termination terminal 231 are pressed against the stub body substrate 20 for mounting, the surface of the central part of the rigid short-circuit termination terminal 231 is also pressed against the surface of the other end of the stub wiring 204. As a result, the path from the stub contact 201 through the first stub wiring 203 and the stub coupling element 202 to the second stub wiring 204 is terminated by short-circuiting the short-circuit termination terminal 231 with the first ground connection line 212 and the second ground connection line 214 at the electrical contact point with the short-circuit termination terminal 231 at the other end of the second stub wiring 204.
[0047] The inward elastic force at the pair of legs of the body 232a of the pair of clips 232 is an elastic force that allows the short-circuit terminal 231 to move when a force is applied to one end side 20a or the other end side 20b of the stub substrate 20, and is an elastic force that maintains electrical contact between the short-circuit terminal 231 and the surface of the other end of the second stub wiring 204, the surface of the other end of the first ground connection wire 212, and the other end of the second ground connection wire 214 when the short-circuit terminal 231 is stationary.
[0048] As shown in Figures 1 and 3, the adjuster 240 has a length L from the tip of the stub contact 201 to the electrical contact position between the short-circuit terminal 231 at the terminal 230 and the other end of the second stub wiring 204. １This is for adjusting the position of the short-circuit termination terminal 231 so that the value becomes [(λ / 2) × n]. In Embodiment 1, the wavelength λ of the test signal is the value obtained by correcting the wavelength shortening factor by the dielectric material constituting the stub substrate 20 to the wavelength calculated from the frequency of the test signal input to the second signal wiring 104.
[0049] Length L １ As the value is set to [(λ / 2) × n], the short-circuit termination terminal 231 is short-circuited and terminated at the electrical contact point with the short-circuit termination terminal 231 at the other end of the second stub wiring 204, the test signal input to the stub contact 201 is reflected at the electrical contact point, and a standing wave is generated between the stub contact 201 and the electrical contact point for the test signal. That is, as the test signal resonates between the stub contact 201 and the electrical contact point, the test signal input to the stub contact 201 is consumed by the path from the first stub wiring 203 and the stub coupling element 202 to the second stub wiring 204.
[0050] As shown in Figure 5, the adjuster 240 comprises a fixing plate 241, an adjustment screw 242, a position adjustment plate 243, and a pair of adjustment plate stoppers 244 and 245. The fixing plate 241 is a steel plate such as an L-shaped conductive plate having a fixing portion 241a and a mounting portion 241b.
[0051] At the center of the other end 20b of the stub body substrate 20, the fixing portion 241a of the fixing plate 241 is fixed to the back surface of the center of the other end 20b of the stub body substrate 20 by fixing screws 246, such that the mounting portion 241b of the fixing plate 241 is positioned away from the other end 20b, that is, in a direction that protrudes from above the other end 20b as shown in Figure 3. A through screw hole 241c is formed in the center of the mounting portion 241b of the fixing plate 241.
[0052] The adjustment screw 242 has a gripping portion 242a and a male threaded portion 242b. The male threaded portion 242b is screwed into a through-hole 241c in the mounting portion 241b of the fixing plate 241 and is rotated by the gripping portion 242a. The position adjustment plate 243 has a through-hole in the center into which the male threaded portion 242b of the adjustment screw 242 is loosely fitted, and one side is fixed to the short-circuit terminal 231 of the terminal 230.
[0053] A pair of adjustment plate stoppers 244 and 245 are fixed to the tip of the male threaded portion 242b of the adjustment screw 242 so as to sandwich the position adjustment plate 243. By rotating the gripping portion 242a of the adjustment screw 242, the rotational motion is converted into linear motion by the male threaded portion 242b and the through-screw hole 241c of the mounting portion 241b, and the pair of adjustment plate stoppers 244 and 245 move up and down along the axis of the male threaded portion 242b.
[0054] The vertical movement of the pair of adjustment plate stoppers 244 and 245 causes the position adjustment plate 243, which is sandwiched between the adjustment plate stoppers 244 and 245, to move up and down, thereby allowing the short-circuit terminal 231 to move up and down. At this time, since the position adjustment plate 243 is loosely fitted to the male screw portion 242b, it does not rotate in conjunction with the rotation of the male screw portion 242b.
[0055] The adjuster 240 can adjust the position of the short-circuit terminal 231 of the terminal 230 with the other end of the second stub wiring 204 by rotating the gripping portion 242a, thereby moving the position adjustment plate 243 up and down.
[0056] As shown in Figure 1, the adjuster 300 adjusts the distance L between the probe body 100 and the stub body 200 to adjust the distance L between the application contact 101 and the stub contact 201. ２ This is for adjusting the wavelength to a natural number multiple of 1 / 4 of the wavelength λ [(λ / 4) × m] (where m is a natural number). The diagram shows the case where m is 1.
[0057] The first adjuster 300A of the pair of adjusters 300 is mounted between the surface of one side 10c of the substrate 10 and the surface of one side 20c of the stub body substrate 20. The second adjuster 300B of the pair of adjusters 300 is mounted between the surface of the other side 10d of the substrate 10 on the probe body 100 and the surface of the other side 20d of the stub body substrate 20 on the stub body 200.
[0058] In Embodiment 1, two adjusters 300A and 300B are used, but one adjuster may be used, or three or more adjusters may be used to more securely attach the probe body 100 and the stub body 200. The first adjuster 300A and the second adjuster 300B are structurally identical except for the attachment position of the probe body 100 and the stub body 200, so they will be described as adjuster 300.
[0059] The adjuster 300 is a jack, and as shown in Figure 6, it has a first arm (left leg) 301, a second arm (right leg) 302, an adjustment screw rod 303, a first connecting body 304, and a second connecting body 305. The connecting surfaces of the first connecting body 304 and the second connecting body 305 correspond to the load-receiving surfaces of the jack's lift surface, for example, the lift surface by the first arm and the surface of the leg, for example, the lift surface by the second arm.
[0060] The first connector 304 and the second connector 305 are each made of a conductive or non-conductive resin. As shown in Figure 1, the connection surface of the first connector 304 contacts the surface of the substrate 10 on the probe body 100, and the substrate 10 is fixed to the first connector 304. As shown in Figure 1, the connection surface of the second connector 305 contacts the surface of the substrate 20 on the stub body 200, and the substrate 20 is fixed to the second connector 305.
[0061] By rotating the gripping portions 303a and 303b of the adjustment screw rod 303 in the adjustment device 300, both ends of the first arm 301 and both ends of the second arm 302 move up and down along the threaded portion 303c of the adjustment screw rod 303, and the distance between the connection surface of the first connector 304 and the connection surface of the second connector 305 is changed.
[0062] Since the connection surface of the first connector 304 and the connection surface of the second connector 305 are always kept parallel, the surface of the substrate 10 and the surface of the substrate 20 are also always kept parallel. As a result, the distance between the probe body 100 and the stub body 200 is changed, and the distance L between the application contact 101 and the stub contact 201 is changed. ２ The interval L has also been changed. ２ It can be adjusted to [(λ / 4) × m].
[0063] When a test signal is applied to the wiring for electronic components from the application contact 101, a standing wave is generated in the wiring due to the test signal. The standing wave generated in the wiring due to the test signal flowing from the application contact 101 towards the stub contact 201 in the wiring for electronic components has a spacing L ２ By setting the potential to [(λ / 4) × m], the potential reaches its maximum value (local maximum) at the location of the wiring for the electronic component to which the stub contact 201 is electrically connected, and reaches its minimum value (local minimum) at the location of the wiring for the electronic component to which the stub contact 201 is electrically connected.
[0064] Next, a method for using the immunity performance evaluation probe according to Embodiment 1 to evaluate the immunity performance of the DUT 2 mounted on the printed circuit board 1 will be explained with reference to Figure 7. First, the probe body 100 and the stub body 200 are assembled using a pair of adjusters 300A and 300B to form the immunity performance evaluation probe.
[0065] In other words, it is assembled as follows: The surface of the substrate 10 of the probe body 100 is brought into contact with the connection surface of the first connector 304 of the pair of adjusters 300A and 300B, and the probe body 100 is fixed to the first connector 304 of the adjusters 300A and 300B. The surface of the substrate 20 for the stub body of the stub body 200 is brought into contact with the connection surface of the second connector 305 of the pair of adjusters 300A and 300B, and the stub body 200 is fixed to the second connector 305 of the adjusters 300A and 300B.
[0066] When the probe body 100 and the stub body 200 are attached to the pair of regulators 300A and 300B, the surface of the substrate 10 in the probe body 100 and the surface of the stub substrate 20 in the stub body 200 are parallel. Since the first regulator 300A fixes the one-side 10c side of the substrate 10 and the one-side 20c side of the stub substrate 20, and the second regulator 300B fixes the other-side 10d side of the substrate 10 and the other-side 20d side of the stub substrate 20, the fixing of the probe body 100 and the stub body 200 to the regulators 300A and 300B becomes stable and firm.
[0067] Next, with respect to the test signal from the signal generator 3 connected to the connector 130 in the probe body 100 via the cable 4, in the stub body 200, the length L from the tip of the stub contact 201 to the electrical contact position between the short-circuit terminal 231 in the terminal 230 and the other end of the second stub wiring 204 is adjusted using the adjuster 240 so that it becomes [(λ / 2)×n]. Also, the distance L between the application contact 101 and the stub contact 201 is adjusted to [(λ / 4)×m] using the pair of regulators 300A and 300B. １ to [(λ / 2)×n]. Also, using the pair of regulators 300A and 300B, the distance L between the application contact 101 and the stub contact 201 is adjusted to [(λ / 4)×m]. ２ to [(λ / 4)×m].
[0068] Next, the probe for immunity performance evaluation thus completed is attached to the printed circuit board 1. That is, it is attached as follows. In the printed circuit board 1 on which the electronic component 2 such as an LSI or an IC to be the DUT is mounted, the application contact 101 in the probe body 100 and the stub contact 201 in the stub body 200 are electrically connected to the electronic component wiring 1S connected to the signal terminal which is the signal terminal or the power supply terminal in the electronic component 2.
[0069] At this time, the application contact 101 in the probe body 100 is electrically connected to the electronic component wiring 1S in a direction close to the electronic component 2. The first ground contact 111 in the probe body 100 and the first ground contact 211 in the stub body 200 are electrically connected to the ground wiring 1G connected to the ground terminal in the electronic component 2.
[0070] Similarly, the second ground contact 121 on the probe body 100 and the second ground contact 221 on the stub body 200 are electrically connected to the ground wiring. The ground wiring connected to the ground terminal on the electronic component 2 is shown, but the ground wiring may also be wiring connected to the reference potential on the printed circuit board 1.
[0071] A cable 4 electrically connects the connector 130 on the probe body 100 to the signal generator 3, so that the test signal output from the signal generator 3 is input to the probe body 100. The electronic components mounted on the printed circuit board 1 are set to an operating state, and the test signal from the signal generator 3 is input via the cable 4.
[0072] The test signal input to the connector 130 on the probe body 100 is applied to the electronic component wiring 1S via the second signal wiring 104 - signal coupling element 102 - first signal wiring 103 - application contact 101. The signal coupling element 102 allows the high-frequency test signal to flow to the electronic component wiring 1S, but blocks the current flowing through the electronic component wiring 1S to operate the electronic component 2, so there is no risk of it flowing back from the application contact 101 and being applied to the signal generator 3.
[0073] The test signal applied to the wiring 1S for electronic components is input to the electronic component 2 via the wiring 1S located on the electronic component 2 side, and is used to evaluate the immunity performance of the electronic component 2. On the other hand, the test signal applied to the wiring 1S for electronic components is also branched to the wiring 1S for electronic components located on the opposite side from the electronic component 2.
[0074] The test signal branched off to the opposite side of electronic component 2 is transmitted through the distance L between the application contact 101 on the probe body 100 and the stub contact 201 on the stub body 200. ２ Because the voltage is set to [(λ / 4) × m], the potential is at its minimum value (local minimum) at the position of the wiring 1S for the electronic component to which the stub contact 201 is electrically connected.
[0075] Furthermore, the test signal branched off to the opposite side of the electronic component 2 flows through the stub body 200 from the stub contact 201 through the first stub wiring 203, the stub coupling element 202, and the second stub wiring 204 to the short-circuit terminal 231 at the terminal 230, and the distance L from the tip of the stub contact 201 to the electrical contact position between the short-circuit terminal 231 and the other end of the second stub wiring 204 １ Because the ratio is set to [(λ / 2) × n], a standing wave is generated between the tip of the stub contactor 201 and the electrical contact position with respect to the test signal.
[0076] Due to the generation of standing waves in the stub body 200, the potential at the location of the wiring 1S for electronic components to which the stub contact 201 is electrically connected becomes equal to the potential at the short-circuit terminal 231, that is, to ground potential.
[0077] At the location of the wiring 1S for electronic components to which the stub contact 201 is electrically connected, the potential of the test signal reaches its minimum value (local minimum), and the stub body 200 brings it to ground potential. This prevents the test signal from flowing from the location where the stub contact 201 is electrically connected to the wiring 1S for electronic components on the opposite side from the electronic component 2, and prevents the test signal from flowing to an electronic component or circuit other than the DUT2 connected to the wiring 1S for electronic components. In other words, the test signal is reliably decoupled from an electronic component or circuit other than the DUT2.
[0078] After the immunity performance evaluation test against DUT2 is completed, the immunity performance evaluation probe can be easily removed from the printed circuit board 1 by simply releasing the electrical connection between the application contact 101, the first ground contact 111, and the second ground contact 121 of the probe body 100 and the stub contact 201, the first ground contact 211, and the second ground contact 221 of the stub body 200.
[0079] The immunity performance evaluation probe according to Embodiment 1 comprises a test signal application probe body 100 having a test signal application contact 101 that contacts and electrically connects to the wiring 1S for electronic components 2 mounted on a printed circuit board 1, a stub contact 201 that contacts and electrically connects to the wiring 1S for electronic components, a terminal 230, and a length L from the stub contact 201 to the terminal 230. １ A stub body 200 having an adjuster 240 for adjusting the position of the terminal 2230 to the length at which the test signal resonates, and the distance L between the test signal application contact 101 and the stub contact 201. ２ Since it is equipped with an adjustment device 300 for adjusting the settings, an immunity performance evaluation test can be easily performed on the electronic components 2 mounted on the printed circuit board 1 by simply connecting the test signal application contact 101 and the stub contact 201 to the wiring 1S for the electronic components.
[0080] Furthermore, in the immunity performance evaluation probe according to Embodiment 1, the adjuster 240 in the stub body 200 has a length L from the stub contact 201 to the terminal 230. １ The distance L can be adjusted to [(λ / 2) × n], and the adjustment device 300 is the distance L between the test signal application contact 101 and the stub contact 201. ２ Since it can be adjusted to [(λ / 4) × m], decoupling can be reliably achieved with a test signal such as a sinusoidal AC, and with a different electronic component or circuit than the electronic component 2 under test, enabling highly accurate immunity performance evaluation tests.
[0081] It should be noted that any component of the embodiment can be modified, or any component of each embodiment can be omitted.
[0082] The immunity performance evaluation probe according to this disclosure is suitable as an immunity performance evaluation probe used to evaluate the immunity performance of electronic components such as LSIs or ICs mounted on a printed circuit board.
[0083] 100 Test signal application probe body, 10 Probe body substrate, 101 Application contact, 102 Signal coupling element, 103 First signal wiring, 104 Second signal wiring, 111 First ground contact, 112 First ground wiring, 121 Second ground contact, 122 Second ground wiring, 200 Stub body, 20 Stub body substrate, 201 Stub contact, 202 Stub coupling element, 203 First stub wiring, 204 Second stub wiring, 211 First ground contact, 212 First ground connection wire, 221 Second ground contact, 222 Second ground connection wire, 230 Terminal, 240 Adjuster, 300, 300A, 300B Adjuster, 301 First arm, 302 Second arm, 303 adjustable screw rod, 304 first connector, 305 second connector.
Claims
1. An immunity performance evaluation probe comprising: a test signal application probe body having a test signal application contact that contacts and electrically connects to wiring for electronic components connected to power or signal IC terminals of electronic components mounted on a printed circuit board, and a signal coupling element, which applies a test signal from the test signal application contact to the wiring for electronic components via the signal coupling element; a stub body having a stub contact that contacts and electrically connects to the wiring for electronic components, a terminal, a stub coupling element interposed between the stub contact and the terminal, and an adjuster for adjusting the position of the terminal so that the length from the stub contact to the terminal is the length at which the test signal resonates; and an adjuster for adjusting the distance between the test signal application contact and the stub contact.
2. A test signal application probe body having a test signal application contact that contacts and electrically connects to wiring for electronic components connected to power or signal IC terminals of electronic components mounted on a printed circuit board, a first signal wire with one end electrically connected to the test signal application contact, a signal coupling element with one electrode electrically connected to the other end of the first signal wire, and a second signal wire with one end connected to the other electrode of the signal coupling element and to which a test signal is applied; a stub body having a stub contact that contacts and electrically connects to the wiring for electronic components, a first stub wire with one end electrically connected to the stub contact, a stub coupling element with one electrode electrically connected to the other end of the first stub wire, a second stub wire with one end connected to the other electrode of the stub coupling element, a terminal that electrically contacts the other end of the second stub wire, and an adjuster for adjusting the electrical contact position of the terminal with respect to the other end of the second stub wire. An immunity performance evaluation probe comprising: an adjuster for adjusting the distance between the contact for applying the test signal and the contact for the stub.
3. The test signal application probe body has a rectangular probe body substrate having a pair of end sides and a pair of side sides, the test signal application contact is mounted on one of the pair of end sides of the probe body substrate, the first signal wiring is formed on the surface of the probe body substrate, extending parallel to the side side from one end side to the other end side of the pair of end sides to the position of one electrode of the signal coupling element, the signal coupling element is a capacitor on the surface of the probe body substrate with one electrode arranged on one end side and the other electrode on the other end side, the second signal wiring is formed on the surface of the probe body substrate, extending parallel to the side side from the position of the other electrode of the signal coupling element to the other end side, The immunity performance evaluation probe according to claim 2, wherein the test signal application probe body further comprises a first ground contact attached to one of a pair of side edges at one end edge of the probe body substrate, a first ground wiring formed along one side edge of the probe body substrate from one end edge to the other end edge, and a connector attached to the other end edge of the probe body substrate, having a core wire electrically connected to the second signal wiring and an outer conductor electrically connected to the first ground wiring.
4. The test signal application probe body has a rectangular probe body substrate having a pair of end sides and a pair of side sides, the test signal application contact is mounted in the center of one of the pair of end sides of the probe body substrate, the first signal wiring is formed on the surface of the probe body substrate, extending parallel to the pair of side sides from the center of one end side to the other end side of the pair of end sides to the position of one electrode of the signal coupling element, the signal coupling element is a capacitor on the surface of the probe body substrate with one electrode arranged on one end side and the other electrode on the other end side, the second signal wiring is formed on the surface of the probe body substrate, extending parallel to the pair of side sides from the position of the other electrode of the signal coupling element to the center of the other end side, The probe for evaluating immunity performance according to claim 2, further comprising: a first ground contact mounted on one of a pair of side edges at one end of the probe substrate; a first ground wiring formed extending from one end to the other along one side of the probe substrate; a second ground contact mounted on the other of a pair of side edges at one end of the probe substrate; a second ground wiring formed extending from one end to the other along the other side of the probe substrate; and a connector mounted in the center of the other end of the probe substrate, having a core wire electrically connected to the second signal wiring and an outer conductor electrically connected to the first ground wiring and the second ground wiring.
5. The stub body has a rectangular stub body substrate having a pair of end sides and a pair of side sides, the test signal application contact is mounted on one of the pair of end sides of the stub body substrate, the first stub wiring is formed on the surface of the stub body substrate, extending parallel to the side side from one end side to the other end side of the pair of end sides to the position of one electrode of the stub coupling element, the stub coupling element is a capacitor on the surface of the stub body substrate with one electrode on one end side and the other electrode on the other end side, the second stub wiring is formed parallel to the side side on the surface of the stub body substrate, extending parallel to the side side from the position of the other electrode of the stub coupling element to the other end side, and the terminal has a flat short-circuit terminal whose surface is positioned facing the surface of the stub body substrate. The immunity performance evaluation probe according to any one of claims 2 to 4, wherein the stub body further comprises a first ground contact mounted on one of a pair of side edges at one end edge of the substrate for the stub body, and a first ground connection line formed along one side edge of the substrate for the stub body from one end edge to the other end edge, with one end electrically connected to the first ground contact and the other end electrically connected to the short-circuit terminal.
6. The stub body has a rectangular stub body substrate having a pair of end sides and a pair of side sides, the test signal application contact is mounted on the central part of one of the pair of end sides of the stub body substrate, the first stub wiring is formed on the surface of the stub body substrate, extending parallel to the pair of side sides from the central part of one end side to the other end side of the pair of end sides to the position of one electrode of the stub coupling element, the stub coupling element is a capacitor on the surface of the stub body substrate with one electrode arranged on one end side and the other electrode on the other end side, the second stub wiring is formed parallel to the pair of side sides on the surface of the stub body substrate, extending parallel to the pair of side sides from the position of the other electrode of the stub coupling element to the central part of the other end side, the terminal has a flat short-circuit terminal whose surface faces the surface of the stub body substrate and is positioned between one side and the other side, The stub body further comprises a first ground contact mounted on one of a pair of side edges at one end of the stub body substrate, a first ground connection line formed extending from one end to the other along one side of the stub body substrate, with one end electrically connected to the first ground contact and the other end electrically connected to one end of the short-circuit terminal, the immunity performance evaluation probe according to any one of claims 2 to 4.
7. The immunity performance evaluation probe according to any one of claims 1 to 6, wherein the adjusting device is a jack having a first arm, a second arm, an adjusting screw rod, a first connector, and a second connector, the test signal application probe body is fixed to the first connector, the stub body is fixed to the second connector, and the distance between the first connector and the second connector is changed by rotating the adjusting screw rod.