JP2015064290A - Circuit board inspection device - Google Patents

Abstract

Insulation inspection between conductor patterns and part inspection of electronic parts can be performed while avoiding complication of the apparatus configuration and deterioration of the inspection signal, and a floating power supply unit has a simpler structure. An inspection apparatus A as a second inspection unit 5 that is directly connected to a probe pin 21 in contact with a conductor pattern group GP1 to GP3 via a wiring and performs component inspection on integrated circuits IC1 to IC3, B and C, and a floating power supply unit 9 for supplying two voltages V1 and V2, and the control unit 6 always connected one conductor pattern group GP3 of the conductor pattern groups GP1 to GP3 to a low potential. The inspection apparatus C that executes the connection process L times in the state and performs the insulation inspection process, and performs the component inspection on the integrated circuit IC3 that constitutes one conductor pattern group GP3 connected to the low potential includes the power supply unit 8 The other inspection devices A and B operate with the supply of voltages V2 and V3. [Selection] Figure 1

Description

  The present invention relates to a circuit board inspection apparatus that performs a predetermined electrical inspection on a circuit board in which a conductor pattern is formed and an electronic component connected to the conductor pattern is incorporated.

  As this type of circuit board inspection apparatus, the present applicant has already proposed the circuit board inspection apparatus disclosed in Patent Document 1 below. In this circuit board inspection apparatus, the control unit specifies all conductor patterns connected in a chain via electronic components based on the conductor pattern data and the electronic component connection data as one conductor pattern group, and the conductor Performing a first process of supplying an inspection signal between any conductor pattern in one conductor pattern group and any conductor pattern in another conductor pattern group when there are a plurality of pattern groups; Each of the conductors based on a physical quantity generated between the conductor pattern of one conductor pattern group and the conductor pattern of another conductor pattern group in accordance with the supply of the inspection signal when the inspection unit executes the first process. Inspect the insulation between patterns.

  Therefore, according to this circuit board inspection apparatus, the conductor pattern and the electronic component included in one conductor pattern group are basically maintained at the same potential, so that the electronic component mounted on the circuit board is damaged. Thus, it is possible to surely inspect the insulation state between the conductor patterns that should be insulated without causing them. Further, in this circuit board inspection apparatus, it is possible to calculate, for example, a resistance value of an electronic component mounted on the circuit board, and to perform a quality inspection (component inspection) of the electronic component based on the calculated resistance value. It has become.

  Further, as a configuration for providing another operation waveform or the like from an external measuring instrument to an electronic component (IC (integrated circuit)) on a circuit board to enable, for example, a simple function test, the following Patent Document 2 is disclosed. Also known is a configuration disclosed in the prior art, that is, a configuration including an external input / output terminal and a switch for switching a probe pin attached to each arm to either the scanner board side or the external input / output terminal side. It has been.

  However, the above-described conventional circuit board inspection apparatus has the following problems to be improved. That is, in order to carry out component inspection for electronic components such as the above-described function test as well as the inspection of the insulation state between conductor patterns using this circuit board inspection device, it is disclosed in the above-mentioned Patent Document 2. Must be configured so that the probe pin is switched to the scanner board side when inspecting the insulation state and the probe pin is switched to the external input / output terminal side when performing component inspection. Therefore, in such a configuration, the device configuration becomes complicated by the addition of the switch, and the inspection signal for component inspection deteriorates when passing through the switch (signal attenuation or noise mixing). ) Existed and there was a need to improve this problem.

  Therefore, in order to improve this problem, the applicant of the present application disclosed in Japanese Patent Application No. 2012-200288, a circuit that can perform insulation inspection between conductor patterns and component inspection of electronic components while avoiding complicated device configuration and deterioration of inspection signals. A board inspection system is proposed. In addition, since this circuit board inspection apparatus performs an insulation inspection in a state where the electronic components are mounted, not all the insulation inspections between the individual conductor patterns, but all that are connected in a chain via the electronic components. The conductor pattern is specified as one conductor pattern group, and the conductor pattern that does not constitute the conductor pattern group is specified, and the insulation state between the inspection target parts (that is, the insulation state between the different conductor pattern groups, the conductor pattern) The insulation state between the group and the conductor pattern that does not constitute the conductor pattern group, and the insulation state between the conductor patterns that do not constitute the conductor pattern group) are inspected.

  Further, in this circuit board inspection apparatus, a second inspection unit that performs component inspection on an electronic component built in the circuit board is provided for each electronic component that performs component inspection, and is floated on each second inspection unit. By supplying the operating voltage from the power supply unit and exchanging data and signals with the second inspection unit via the isolator, the first inspection unit that performs the insulation inspection It has a floating structure. As a result, in this circuit board inspection apparatus, the scanner that switches the signal from the first inspection unit and supplies it to any probe pin of the fixture or separates the first inspection unit from all the probe pins, and the probe pin are provided. While always connecting (direct connection) with wiring, the inspection device and probe pins constituting the second inspection unit are also always connected (direct connection) with wiring so that the scanner on the first inspection unit side and the second inspection unit side are connected. The inspection apparatus does not need to be switched with a switch.

Japanese Patent No. 4532570 (page 3-6, Fig. 1) Japanese Patent Laid-Open No. 6-331699 (2nd page, FIG. 3)

  However, the circuit board inspection apparatus described above (the circuit board inspection apparatus proposed in Japanese Patent Application No. 2012-200288) has the following problems to be improved. That is, in this circuit board inspection apparatus, it is necessary to generate and supply an operating voltage individually in the floating power supply unit for each second inspection unit individually provided for each electronic component that performs component inspection. There is a problem to be improved that the composition of the parts is complicated.

  By the way, in the same manner as in this circuit board inspection apparatus, each conductor constituting one conductor pattern group as a part to be inspected in order to avoid damage to electronic components existing in the conductor pattern group in the insulation inspection. When adopting a configuration that controls the scanner so that the pattern has the same potential, and adopting a multiple method that can inspect the insulation state between multiple inspection target parts at high speed with a small number of steps, multiple inspection objects One of the parts to be inspected can always be regulated to a low potential in the insulation inspection.

  Accordingly, the applicant of the present application pays attention to the characteristics of the multiple method, in which one inspection target part of a plurality of inspection target parts can be always regulated to a low potential in the insulation inspection. I thought that it could be improved.

In this multiple method, a plurality of inspection target parts whose insulation states are to be inspected are grouped into two groups (A group and B group). For example, the inspection target parts in the A group are mutually connected. Based on the current flowing between them and the potential difference between the high potential and the low potential at the same potential (low potential) and the inspection target parts in the B group are the same potential (high potential). By calculating the mutual resistance value (insulation resistance value), it is inspected whether the insulation state between both groups is good. And this test | inspection is performed a predetermined number of times, changing the content of grouping (inspection object part which belongs to each group) according to a predetermined rule. In this case, the number of inspections L (the number of groupings; hereinafter, the number of steps) required to inspect whether the insulation state between one inspection target part and all other inspection target parts is good or not. say) is the number of inspected portion when the K, there is log ₂ K or more is defined by the integer closest to log ₂ K (e.g., when K = 20, the _log 2 20 ≒ 4.32 Therefore, the number of inspections (number of steps L is 5 times). For this reason, in this multiple method, compared with a method (so-called brute force method) in which insulation inspection is sequentially performed for all combinations in which two of a plurality of inspection target portions are selected, insulation between the inspection target portions is performed. Whether or not the state is good can be inspected with a small number of times.

  The present invention has been made in view of such problems, and can perform insulation inspection between conductor patterns and component inspection of electronic components while avoiding complicated device configuration and deterioration of inspection signals, and a floating power supply unit. The main object is to provide a circuit board inspection apparatus that can have a simpler structure.

In order to achieve the above object, a circuit board inspection apparatus according to claim 1, wherein a plurality of conductor patterns are formed and an electronic component connected to any one of the plurality of conductor patterns is incorporated. A pair of fixtures in which a plurality of probe pins that are brought into contact with the plurality of conductor patterns on the substrate are erected, and a pair of connection terminals, and an insulation state between the inspection target parts connected to the pair of connection terminals. A first inspection unit that inspects one of the connection terminals at a low potential and the other connection terminal at a high potential, and includes a plurality of changeover switches, and via a wiring. The switch is disposed between the fixture and the first inspection unit in a state of being connected to the plurality of probe pins and the pair of connection terminals, and the on / off state of the changeover switch is controlled. Any of the separated state in which all of the plurality of probe pins are separated from the pair of connection terminals and the connection state in which any of the plurality of probe pins is connected to the pair of connection terminals. A plurality of conductor pattern groups composed of all the conductor patterns connected in a chain via the electronic components, and independent conductor patterns that do not constitute the conductor pattern groups Control the scanner as K (K is an integer of 3 or more) inspection target parts, and set a part of the K inspection target parts as the first group The low potential and the high power are obtained by connecting the inspection target part of the first group to any one of the pair of connection terminals. All of the test target parts except the first group of test target parts among the K test target parts are set as the second group and connected to the potential of any one of By connecting two groups of inspection target parts to the other connection terminal of the pair of connection terminals, connection processes for connecting to the other potential of the low potential and the high potential are set as the two groups, respectively. Executing L times (L is log ₂ K or more and the closest integer to log ₂ K) while changing the combination of the inspection target parts, and each time the connection process is executed, the control for the first inspection unit is performed. A control unit that executes an insulation inspection process for inspecting an insulation state between inspection target parts connected to the pair of connection terminals; the first inspection unit; the scanner; A circuit board inspection apparatus including a power supply unit that supplies a first operating voltage to the control unit, and contacts the conductor pattern connected to the electronic component constituting one of the conductor pattern groups A second inspection unit that is directly connected to the probe pin through a wiring and performs component inspection on the electronic component, and is electrically insulated from the first operating voltage and electrically insulated from each other. A floating power supply unit for supplying a second operating voltage, and the control unit is configured to perform the L times in a state where one conductor pattern group of the plurality of conductor pattern groups is always connected to the low potential. The component inspection for the electronic component that executes the connection processing and the insulation inspection processing to form the one conductor pattern group connected to the low potential in the second inspection section. The second inspection unit that performs the operation is performed by receiving the supply of the first operating voltage from the power supply unit, and all other second inspection units other than the second inspection unit are connected to the floating power supply unit from the floating power supply unit. Operates in response to the supply of the second operating voltage.

  The circuit board inspection apparatus according to claim 1, wherein the control unit combines the K inspection target parts in the circuit boards for inspecting the insulation state between the inspection target parts to be combined as the first group and the second group. The first group of test target sites are connected to one of a low potential and a high potential, and the second group of test target sites is the other of the low potential and the high potential. The connection process to connect to the potential is performed L times while changing the combination of the parts to be inspected set as both groups, and each time the connection process is performed, the control for the first inspection unit is executed and the pair of Insulation inspection processing by a multiple method for inspecting the insulation state between the inspection target parts connected to the connection terminals is executed.

  Further, in this circuit board inspection apparatus, when there are a plurality of electronic components that constitute a conductor pattern group as one inspection target portion and the component inspection is performed, one electronic component of the electronic component is detected. A part is defined as an inspection target part to which a low potential is always applied in an insulation inspection process using a multiple method, and is generated based on a reference potential on the same power supply unit side as the control unit, the first inspection unit, and the like. Inspection is performed with an inspection device as a second inspection unit using the operation voltage as the operation voltage. For the remaining electronic components, one or more second operating voltages that are electrically insulated from the first operating voltage on the power supply unit side and also electrically isolated from each other are operated when there are a plurality of electronic components. Inspection is performed at the second inspection unit, which is used as a working voltage.

  Therefore, according to this circuit board inspection apparatus, unlike the circuit board inspection apparatus described in the background art, one second inspection section among all the second inspection sections provided for each electronic component subjected to component inspection is provided. Can supply the first operation voltage from the same power supply unit as the control unit, the first inspection unit, etc. as the operation voltage, so that the operation for the second inspection unit generated individually by the floating power supply unit As a result of being able to reduce only one type of voltage, the configuration of the floating power supply unit can be simply configured as much as compared with the configuration in which the floating power supply unit generates operating voltages for all the second inspection units. Can do.

1 is a configuration diagram showing a configuration of a circuit board inspection device 1. FIG. FIG. 4 is an enlarged view of a main part of the circuit board 51 for explaining a conductor pattern P in the circuit board 51 and the structure of each electronic component. FIG. 5 is a correspondence diagram showing net names for each inspection target site in the circuit board 51. FIG. 6 is a correspondence diagram between each net (net1 to net8) and a voltage applied to the net in each step in an insulation test by a multiple method.

  Hereinafter, an embodiment of a circuit board inspection apparatus will be described with reference to the accompanying drawings.

  First, the configuration of the circuit board inspection apparatus 1 will be described. A circuit board inspection apparatus 1 shown in FIG. 1 includes a fixture (pin board) 2, a scanner 3, a first inspection unit 4, a second inspection unit 5, a control unit 6, a storage unit 7, a power supply unit 8, and a floating power supply unit 9. The circuit board 51 is configured to be able to perform a predetermined electrical inspection.

  The circuit board 51 to be inspected is a component-embedded circuit board in which electronic components (for example, a resistor, a capacitor, and an integrated circuit) are built, and a conductor pattern connected to the built-in electronic component. Is formed between the surface of the circuit board 51 (upper surface as an example in this example) and the inside of the circuit board 51 on which the electronic components are arranged via vias (or through holes) (not shown). ing.

  As an example, as shown in FIG. 1, the circuit board 51 includes a plurality of conductor pattern groups GP each composed of all conductor patterns connected in a chain via electronic components (in this example, 6 One conductor pattern group GP1 to GP6, hereinafter referred to as “conductor pattern group GP” unless otherwise distinguished), and a plurality of independent conductor patterns P that do not constitute the conductor pattern group GP (in this example, two conductor patterns as an example) P16, P17) are formed. In addition, the conductor pattern groups GP1 to GP3 among the conductor pattern groups GP1 to GP6 are subjected to component inspection by the second inspection unit 5 (in this example, inspection apparatuses A, B, and C of the second inspection unit 5) as described later. Includes conductor patterns connected in a chain via integrated circuits IC1, IC2 and IC3 as electronic components.

  First, the conductor pattern group GP will be specifically described with reference to FIG. 2 by taking two of the conductor pattern groups GP1 and GP2 of the conductor pattern groups GP1 to GP3 as examples. The conductor pattern group GP1 includes all the conductor patterns P1 connected in a chain via an integrated circuit IC1 (for example, a filter element having a predetermined frequency characteristic) built in the circuit board 51, a resistor R1, and a capacitor C1. ~ P4. Further, the conductor pattern group GP2 has a voltage corresponding to the value indicated by the logic input to the integrated circuit IC2 (for example, the input pins connected to the conductor patterns P11, P12, and P9) built in the circuit board 51. (D / A converter that outputs from output pin connected to conductor pattern P8), resistors R2 to R4, and all conductor patterns P5 to P15 connected in a chain via capacitors C2 and C3 Yes. The integrated circuit IC3 included in the conductor pattern group GP3 is composed of an amplifier (not shown). Further, the integrated circuit IC3 includes, as an example, four terminals: a power supply terminal, a ground terminal, an input terminal, and an output terminal. As a result, the conductor pattern group GP3 is assumed to be composed of, for example, four conductor patterns P (not shown) connected in a chain via the integrated circuit IC3.

  Next, the independent conductor pattern P that does not constitute the conductor pattern group GP will be specifically described with reference to FIG. 2 taking the conductor pattern P16 as an example. A plurality of electronic components are mounted on the surface of the circuit board 51 later, and as shown by broken lines in the drawing, the conductor pattern P16 has a capacitor C11 mounted later with the conductor pattern P15; Only the resistor R11 to be mounted later is connected between the conductor pattern P13. Therefore, when the circuit board 51 is inspected by the circuit board inspection apparatus 1, the conductor pattern P16 is not a conductor pattern that is connected to other conductor patterns P via electronic components (that is, conductor pattern group). It is in the state of a conductor pattern that does not constitute a GP).

  The fixture 2 is configured to include a plurality (m pieces) of probe pins 21. The fixture 2 is supported so as to be movable toward and away from the circuit board 51 by a support mechanism (not shown) above the circuit board 51 mounted on the upper surface of a mounting table (not shown). Further, the plurality of probe pins 21 are erected at positions corresponding to contact portions (contact points) of the conductor pattern P to be contacted on the surface on the mounting table side (the lower surface in this example) of the fixture 2. In this example, one contact portion is defined for each conductor pattern P. For this reason, as many probe pins 21 as the conductor pattern P are provided. With this configuration, when the fixture 2 is moved to a state (probing state) in which each probe pin 21 comes into contact with a corresponding contact portion, the circuit board 51 is placed between the fixture 2 and the mounting table via each probe pin 21. Hold and hold.

  The scanner 3 includes a plurality of changeover switches, and is disposed between the fixture 2 and the first inspection unit 4 as shown in FIG. The scanner 3 is connected to a plurality of (m) probe pins 21 via wiring (the number is m), and a pair of connection terminals 4a and 4b (to be described later) of the first inspection unit 4 and wiring (2). Book wiring). Further, the scanner 3 is separated so that all of the plurality of probe pins 21 are separated from the pair of connection terminals 4 a and 4 b of the first inspection unit 4 by controlling the on / off states of the plurality of changeover switches by the control unit 6. The state and an arbitrary probe pin 21 of the plurality of probe pins 21 are connected to any one of the pair of connection terminals 4a and 4b of the first inspection unit 4, and the one connection terminal Transition to any one of the connection states in which an arbitrary probe pin 21 of the other probe pins 21 excluding the connected probe pin 21 is connected to the other connection terminal of the pair of connection terminals 4a and 4b. Is possible.

  The 1st test | inspection part 4 has a pair of connecting terminal 4a, 4b, and test | inspects the insulation state between the test object site | parts connected to this pair of connecting terminal 4a, 4b. As an example, the 1st test | inspection part 4 is provided with the insulation resistance meter and the process part (all are not shown) with a pair of connection terminals 4a and 4b. With this configuration, the processing unit is controlled by the control unit 6 to operate the insulation resistance meter, and the insulation resistance between the inspection target parts connected to the pair of connection terminals 4a and 4b is measured. By comparing the resistance value of the resistor with a predetermined reference resistance value, the insulation state between the parts to be inspected is inspected (for example, the insulation state is good when the calculated resistance value is equal to or greater than the reference resistance value). When it is less than the reference resistance value, the insulation state is inspected to be defective), and the result data D1 indicating the inspection result is output to the control unit 6.

  In this case, the insulation resistance meter of the first inspection unit 4 has a high potential (generally at the inspection target portion connected to one connection terminal 4a among the inspection target portions connected to the pair of connection terminals 4a and 4b. And a low potential (reference potential G1 to be described later) is applied to another inspection site connected to the other connection terminal 4b. At the same time, the current flowing between the pair of connection terminals 4a and 4b is measured, and the insulation resistance between the inspection target parts is measured based on the potential difference between the high potential and the low potential and the measured current.

  The second inspection unit 5 is connected to each probe pin 21 that is in contact with the conductor pattern P connected to the electronic component that performs component inspection among the electronic components built in the circuit board 51 via n wires. It is always connected and performs component inspection for these electronic components. In this example, there are three electronic components IC1, IC2, and IC3 as an example for executing the component inspection. Therefore, the integrated circuit IC1 that is a filter element corresponds to the number of electronic components that perform the component inspection. An inspection apparatus A (for example, a frequency characteristic measuring device) for measuring and inspecting the frequency characteristics of the semiconductor device and an inspection apparatus B (for example, an integrated circuit) for operating and inspecting the integrated circuit IC2 that is a D / A converter A signal output device capable of outputting a plurality of bits of digital data for operating the IC2, and a voltage measuring device for measuring the output voltage of the integrated circuit IC2, and an inspection device for operating and testing the integrated circuit IC3 which is an amplifier. C (for example, a signal generator and a voltage measuring device that measures the output voltage of the integrated circuit IC3) and three inspection devices (ie, for example, an electronic component that performs component inspection) And a number same number of the inspection apparatus and) as the second inspection unit 5.

  The inspection apparatus A is directly connected to the three conductor patterns P1 to P3 (see FIG. 2) connected to the three terminals of the integrated circuit IC1 via the three probe pins 21 and the three wirings. The device B is directly connected to the six conductor patterns P8 to P13 connected to the six terminals of the integrated circuit IC2 via the six probe pins 21 and the six wires. Although not shown, the inspection apparatus C is directly connected to the four conductor patterns P connected to the four terminals of the integrated circuit IC3 through the four probe pins 21 and the four wires as described above. ing. Thus, in this example, the second inspection unit 5 is connected to the 13 probe pins 21 of the fixture 2 via n (= 13) wires. Further, the inspection apparatuses A, B, and C are electrically insulated (separated) from each other.

  The inspection devices A and B among the inspection devices A, B, and C as the second inspection unit 5 operate based on the voltage (first operation voltage) V1 output from the power supply unit 8. Unlike the first inspection unit 4, the inspection device C, the control unit 6 and the storage unit 7, the voltage supplied from the floating power supply unit 9 (the voltage electrically insulated from the voltage V1 side) is used as the operating voltage. To do. Specifically, the inspection device A of the second inspection unit 5 is electrically insulated from a voltage V2 (a reference potential G1 and voltage V1 described later on the voltage V1 side) supplied from the floating power supply unit 9 to the power supply terminal 5a. The second operating voltage generated based on a reference potential G2 described later is used as the operating voltage. The other inspection device B of the second inspection unit 5 is electrically insulated from the voltage V3 (the reference potential G1 on the voltage V1 side and the voltage V1) supplied from the floating power supply unit 9 to the power supply terminal 5b, and The other second operating voltage generated based on a reference potential G3 described later, which is also electrically insulated from the reference potential G2 and the voltage V2, is operated as an operating voltage.

  The inspection apparatus A of the second inspection unit 5 operates under the control of the control unit 6 (operates based on the control signal Sa output from the control unit 6) to inspect the integrated circuit IC1. A test for the integrated circuit IC1 is performed by generating a test signal and outputting it to the integrated circuit IC1. The inspection apparatus A operates under the control of the control unit 6 and outputs the result data Da indicating the result of the inspection on the integrated circuit IC1 to the control unit 6. Similarly, the inspection apparatus B of the second inspection unit 5 operates under the control of the control unit 6 (operates based on the control signal Sb output from the control unit 6), and inspects the integrated circuit IC2. The test for the integrated circuit IC2 is executed by generating a test signal for output to the integrated circuit IC2. The inspection apparatus B operates under the control of the control unit 6 and outputs the result data Db indicating the result of the inspection on the integrated circuit IC2 to the control unit 6. Note that the exchange of the control signal Sa and the result data Da between the inspection apparatus A and the control unit 6 and the exchange of the control signal Sb and the result data Db between the inspection apparatus B and the control unit 6 are performed via the isolator 10. Done.

  In this way, the inspection devices A and B are electrically insulated from each other, and the voltage V2 and the reference potential G2 supplied to the inspection device A from the floating power supply unit 9 and the inspection device B from the floating power supply unit 9 are supplied. The supplied voltage V3 and its reference potential G3 are electrically insulated from each other, the inspection devices A and B are both electrically insulated from the control unit 6 via the isolator 10, and the inspection devices A and B are wired. Each of the conductor pattern groups GP1 and GP2 connected to the integrated circuits IC1 and IC2 that are directly connected to each other is electrically insulated (configuration that is not connected in a chain via electronic components) Therefore, each inspection apparatus A and B as the second inspection unit 5 is always in a floating state.

  On the other hand, the inspection apparatus C as the second inspection unit 5 is similar to the scanner 3, the first inspection unit 4, the control unit 6, and the storage unit 7, and outputs a voltage (first operating voltage). Operates based on V1. The inspection apparatus C operates under the control of the control unit 6 (operates based on the control signal Sc output from the control unit 6), and generates an inspection signal for inspecting the integrated circuit IC3. By outputting to the integrated circuit IC3, a test on the integrated circuit IC3 is executed. Further, the inspection device C operates under the control of the control unit 6 and outputs the result data Dc indicating the result of the inspection on the integrated circuit IC3 to the control unit 6. This inspection device C operates based on a voltage (first operation voltage) V1 common to the control unit 6. For this reason, the exchange of the control signal Sc and the result data Dc between the inspection apparatus C and the control unit 6 is performed without going through the isolator 10.

  The control unit 6 includes a computer or the like, and executes control for each of the inspection apparatuses A, B, and C as the scanner 3, the first inspection unit 4, and the second inspection unit 5 as described above. Then, an insulation inspection process by a multiple method for the conductor pattern P of the circuit board 51 and a component inspection process for the electronic components (integrated circuits IC1, IC2, IC3 in this example) built in the circuit board 51 are executed.

  The storage unit 7 includes a semiconductor memory such as a ROM and a RAM, an HDD (Hard Disk Drive), and the like. The storage unit 7 stores an operation program for the control unit 6, and the control unit 6 performs the first inspection unit 4. And the result data D1, Da, Db, Dc acquired from the second inspection unit 5 are stored. The storage unit 7 also includes data relating to the circuit board 51, that is, data that can specify the probe pins 21 that are in contact with each conductor pattern P, and each electronic component (resistors R1, R2, R3) connected to each conductor pattern P. , R4, capacitors C1, C2, and C3, and all electronic components including integrated circuits IC1, IC2, and IC3) are previously stored.

In addition, as shown in FIG. 3, the storage unit 7 includes data for identifying the inspection target parts to be inspected by the first inspection unit 4 for identifying the inspection target parts. It is stored in advance corresponding to data (net names: net1 to net8). In addition, as shown in FIG. 4, the storage unit 7 has insulation between inspection target parts (between the inspection target part set in the first group and the inspection target part set in the second group) based on a multiple method. Data for specifying an applied voltage to each inspection target part (each net) for each step in the state inspection is stored in advance. In this case, “Low” in FIG. 4 indicates that a low potential is applied, and “High” indicates that a high potential is applied. Further, since the number K of the inspected portion is eight as shown in FIG. 3, the number of steps in the multiple manner (the number of inspections) L is a is log 2 _K or more at the nearest integer) to log 2 _K For this reason, the steps 1 to 3 are performed three times as shown in FIG.

  The power supply unit 8 is a voltage V1 (based on the reference potential G1) for operating the scanner 3, the first inspection unit 4, the second inspection unit 5 (inspection apparatus C in this example), the control unit 6, and the storage unit 7. Voltage) is generated and output. The floating power supply unit 9 supplies one or more second operating voltages (in this example, voltages V2 and V3) that are electrically insulated from the voltage V1. In this example, as an example, the floating power supply unit 9 is composed of an insulation type DC / DC converter configured using a transformer having two independent secondary windings, and an alternating current induced in each secondary winding. The voltages are respectively converted into voltages V2 and V3 as DC voltages by two electrically rectifying and smoothing circuits which are electrically insulated, and output. With this configuration, the floating power supply unit 9 generates the voltage V2 based on the voltage V1 and the reference potential G2 electrically insulated from the reference potential G1 of the voltage V1, and generates the second inspection unit 5 (in this example, the inspection). Output to the device A), and generates a voltage V3 based on the reference potential G3 electrically insulated from both the voltage V1 and the reference potential G1, and the voltage V2 and the reference potential G2, and generates a second inspection section 5 ( In this example, it is output to the inspection apparatus B). The isolator 10 is disposed between the control unit 6 and the second inspection unit 5, and receives the control signals Sa and Sb output from the control unit 6 and electrically insulates the second inspection unit 5. Output. Further, the isolator 10 inputs the result data Da and Db output from the second inspection unit 5 and outputs them to the control unit 6 while being electrically insulated.

  Next, the operation of the circuit board inspection apparatus 1 will be described with reference to the drawings. It is assumed that the circuit board 51 is placed on a mounting table (not shown) and is sandwiched (held) between the mounting table and the fixture 2.

  In this state, in the circuit board inspection apparatus 1, the control unit 6 first performs an insulation inspection process on the circuit board 51. In this insulation inspection process, the control unit 6 first controls the second inspection unit 5 by outputting the control signals Sa and Sb to the second inspection unit 5 via the isolator 10, and the second inspection unit 5. The inspection devices A and B are shifted to a stopped state (a state where a signal for component inspection is not output to the probe pin 21).

  Next, the control unit 6 combines K conductor pattern groups GP (in this example, conductor pattern groups GP1 to GP6 and independent conductor patterns P (in this example, conductor patterns P16 and P17) that do not constitute the conductor pattern group GP). (K is an integer greater than or equal to 3; 8 in this example) As a part to be inspected, a part of the 8 parts to be inspected (in this example, there are 8 parts to be inspected, so half of 4) The target site is set as the first group, and all the test target sites other than the test target site of the first group among the eight test target sites are set as the second group. Performs control on the scanner 3, and sets each inspection target part of the first group to one of the pair of connection terminals 4a and 4b of the first inspection unit 4 (for example, one of the connection terminals 4a). Potential (high voltage )) And each inspection object part of the second group is connected to the other potential of the pair of connection terminals 4a and 4b (for example, the potential of the other connection terminal 4b (reference potential G1 as a low potential)). Next, the control unit 6 causes the first inspection unit 4 to inspect the insulation state between the two groups, and the control unit 6 executes the control for the scanner 3 so that each group is inspected. By changing the combination of the inspection target parts set as, the first inspection unit 4 is inspected L times (in this example, three times) between the K (8) inspection target parts. Check the insulation state of the.

  Specifically, as shown in FIG. 4, the control unit 6 sets the nets 2, 4, and 4 as the first group to which a high potential is applied in the first combination (step 1) of the examination target parts set as each group. As a second group for applying a low potential (reference potential G1), by combining nets 3, 1, 5, and 7 together, conductor pattern group GP2, conductor pattern group GP4 included in the first group, The first inspection unit 4 is inspected for insulation between the conductor pattern group GP6 and the conductor pattern P17 and the conductor pattern group GP3, conductor pattern group GP1, conductor pattern group GP5, and conductor pattern P16 included in the second group.

  Further, as shown in FIG. 4, the control unit 6 uses the nets 1, 4, 7, and 8 as the first group to which the high potential is applied in the second combination (step 2) of the examination target sites set as each group. Are combined, and nets 3, 2, 5, and 6 are combined as a second group to which a low potential (reference potential G1) is applied, thereby including conductor pattern group GP1, conductor pattern group GP4, and conductor pattern P16 included in the first group. And the 1st test | inspection part 4 test | inspects the insulation state between conductor pattern P17 and conductor pattern group GP3, conductor pattern group GP2, conductor pattern group GP5, and conductor pattern group GP6 which are contained in a 2nd group.

  Further, as shown in FIG. 4, the control unit 6 uses the nets 5, 6, as the first group to which a high potential is applied in the third (last) combination (step 3) of the examination target sites set as each group. 7 and 8 and a second group to which a low potential (reference potential G1) is applied, and by combining nets 3, 2, 1, and 4, a conductor pattern group GP5, a conductor pattern group GP6 included in the first group, The first inspection unit 4 is inspected for insulation between the conductor patterns P16 and P17 and the conductor pattern group GP3, conductor pattern group GP2, conductor pattern group GP1, and conductor pattern group GP4 included in the second group.

  During the execution of the insulation inspection process (during the insulation state inspection by the first inspection unit 4), as described above (as shown in FIG. 4), the conductor pattern group GP1 (net1) and the conductor pattern group GP2 (net2) A low potential and a high potential are switched and applied from the first inspection section 4 to the inspection apparatus A of the second inspection section 5 directly connected to the conductor pattern group GP1 through the probe pin 21 and the wiring. The low potential and the high potential are also switched and applied to the inspection device B of the second inspection section 5 directly connected to the conductor pattern group GP2 via the probe pin 21 and the wiring. Thereby, a high potential is applied between any of the inspection apparatus A and the inspection apparatus B, between the inspection apparatus A and the reference potential G1, and between the inspection apparatus B and the reference potential G1.

  However, as described above, in the inspection apparatuses A and B, the reference potentials G2 and G3 are electrically insulated from each other and the reference potential G1 is electrically insulated from each other, and the voltage V2 that is the respective operating voltage. , V3 are also electrically insulated from each other and are electrically insulated from the voltage V1, and are also electrically insulated from each other by the isolator 10 from the control unit 6 operating at the voltage V1 and the reference potential G1. For this reason, when a high voltage is applied to one of the inspection apparatuses A and B, current flows from the inspection apparatus A to the inspection apparatus B (or from the inspection apparatus B to the inspection apparatus A), from the inspection apparatus A to the control unit 6 and the like. Circuit of the power supply unit 8 side (or the circuit from the power supply unit 8 side such as the control unit 6 to the inspection device A) and the circuit from the inspection device B to the power supply unit 8 side such as the control unit 6 (or Further, current wraparound from the circuit on the power supply unit 8 side such as the control unit 6 to the inspection apparatus B) is prevented. Thereby, the damage of the inspection apparatus A and the inspection apparatus B is avoided.

  In addition, as described above, the inspection apparatus C operates with the voltage V1 based on the same reference potential G1 as the circuit on the power supply unit 8 side such as the control unit 6 as an operation voltage, and therefore other inspection apparatuses A and B Thus, it is not electrically insulated from the power supply unit 8 side. However, as described above (as shown in FIG. 4), the conductor pattern group GP3 (net3) is removed from the first inspection unit 4 during the execution of the insulation inspection process (during the inspection of the insulation state by the first inspection unit 4). A low potential is always applied, and accordingly, a low potential is always applied to the inspection apparatus C of the second inspection unit 5 directly connected to the conductor pattern group GP3 via the probe pin 21 and the wiring. For this reason, current wraparound between the inspection apparatus C and other circuits on the power supply unit 8 side does not occur, and this conductor pattern group GP3 and other inspection target parts (others to which a high potential is applied) Even if the insulation state between the conductor pattern group GP and the conductor pattern P) is poor and current wraparound occurs between the conductor pattern group GP3 and the other inspection target part, this current is Since the current flows between the probe pin 21 and the scanner 3 and the other connection terminal 4b (reference potential G1) of the first inspection unit 4 through the scanner 3, There is no current sneak in between the circuit. As a result, unlike the other inspection devices A and B, the inspection device C is damaged due to current wraparound without adopting a configuration that is electrically insulated from the power supply unit 8 side (a configuration that is floating). Has been avoided.

  Finally, the control unit 6 executes control on the first inspection unit 4 to output the result data D1 indicating the inspection result regarding the insulation state between the inspection target parts, and obtains and stores the result data D1. Store in the unit 7. Thereby, the insulation inspection process is completed.

  Next, the control unit 6 executes component inspection processing for inspecting electronic components (in this example, integrated circuits IC1, IC2, and IC3) built in the circuit board 51. In this component inspection process, the control unit 6 first performs control on the scanner 3 to connect all the m wires connected to the plurality of probe pins 21 to the pair of connection terminals 4 a of the first inspection unit 4. , 4b, the scanner 3 is shifted to the separated state.

  Next, the control unit 6 controls the inspection device A by outputting a control signal Sa to the inspection device A of the second inspection unit 5 through the isolator 10, and performs component inspection on the integrated circuit IC1 (filter element). Let In this case, the inspection apparatus A is connected to the integrated circuit IC1 that is directly connected (meaning that there is no changeover switch) via the three wires and the probe pins 21 connected to these wires. The frequency characteristic of the integrated circuit IC1 is measured by supplying a signal for measuring the frequency characteristic and measuring the signal output from the integrated circuit IC1 at that time. Further, the second inspection unit 5 inspects the integrated circuit IC1 based on whether or not the measured frequency characteristic is included in a predetermined reference range (for example, the measured frequency characteristic is included in the reference range). The product is inspected so that it is a non-defective product when it is out of the standard range and a defective product when it is out of the standard range.

  Subsequently, the control unit 6 controls the inspection device B by outputting a control signal Sb to the inspection device B of the second inspection unit 5 via the isolator 10 to control the integrated circuit IC2 (D / A converter). Have parts inspection run. In this case, the inspection apparatus B is connected to the integrated circuit IC2 that is directly connected (meaning that there is no changeover switch) via the six wires and the probe pins 21 connected to these wires. The signal output device outputs a plurality of patterns of digital data to the input pins of the integrated circuit IC2, and the voltage measuring device measures the output voltage output from the output pins of the integrated circuit IC2 at each pattern and corresponds to each pattern. The integrated circuit IC2 is inspected based on whether or not the output voltage is included in the reference range defined in advance (for example, it is a non-defective product when the voltage value of the output voltage is included in the reference range, When it is out of the reference range, it is inspected as a defective product).

  Subsequently, the control unit 6 controls the inspection device C by outputting a control signal Sc to the inspection device C of the second inspection unit 5 to execute component inspection on the integrated circuit IC3 (amplifier). In this case, the inspection apparatus C is connected to the integrated circuit IC3 connected directly (meaning that no changeover switch is interposed) via the four wires and the probe pins 21 connected to these wires. The signal generator outputs a plurality of patterns of analog signals having different voltage values to the input pin of the integrated circuit IC3, and the voltage measuring device measures the output voltage output from the output pin of the integrated circuit IC3 at each pattern. The integrated circuit IC3 is inspected based on whether or not the output voltage is included in a reference range defined in advance corresponding to the pattern (each voltage value) (for example, the voltage value of the output voltage is within the reference range). If it is included, it is a non-defective product, and if it is out of the reference range, it is a defective product).

  Finally, the control unit 6 executes control on the second inspection unit 5, and results data Da indicating the inspection result of the integrated circuit IC1 by the inspection apparatus A and results indicating the inspection result of the integrated circuit IC2 by the inspection apparatus B. The data Db and the result data Dc indicating the inspection result of the integrated circuit IC3 by the inspection apparatus C are output, and the result data Da, Db, Dc are acquired and stored in the storage unit 7. Thus, the component inspection process is completed, and all the inspection processes for the circuit board 51 are completed. In addition, when the circuit board inspection apparatus 1 includes an output unit (not shown), the control unit 6 reads the result data D1, Da, Db, and Dc from the storage unit 7 and outputs them to the output unit. Thus, when the output unit is configured by a display device, each result data D1, Da, Db, Dc is displayed on the screen of the display device. When the output unit is configured by an external interface circuit, each result data D1, Da, Db, Dc is output to an external device connected to the circuit board inspection apparatus 1 via the external interface circuit.

  Thus, in this circuit board inspection apparatus 1, the control unit 6 combines the K inspection target parts in the circuit boards 51 for inspecting the insulation state between them as a first group. Dividing into inspection object parts and inspection object parts to be combined as the second group (inspection object parts other than the inspection parts combined as the first group), the first group of inspection object parts of the low potential and high potential Either one potential (in the above example, a high potential as an example) is connected, and the inspection target site of the second group is set to the other of the low potential and the high potential (as one example, the reference potential G1 as a low potential). The connection process to be connected is executed L times (three times in this example) while changing the combination of the parts to be examined set as both groups, and the first test is performed each time the connection process is executed. Multiple that controls the part 4 to inspect the insulation state between the inspection target parts connected to the connection terminals 4a and 4b (between the inspection target part of the first group and the inspection target part of the second group). Insulation inspection processing by the method is executed.

  Further, in this circuit board inspection apparatus 1, when there are a plurality of integrated circuit ICs that constitute a conductor pattern group GP as one inspection target part and subjected to component inspection, One of the integrated circuit ICs (in the above example, the integrated circuit IC3) is defined as an inspection target part (net) to which a low potential is always applied in the insulation inspection process by the multiple method, and the control unit 6 and the second Inspection is performed by the inspection apparatus C as the second inspection unit 5 using the voltage V1 generated with reference to the reference potential G1 on the same power supply unit 8 side as that of the first inspection unit 4 or the like. For the remaining integrated circuit ICs (in the above example, the integrated circuits IC1 and IC2), two voltages V2 and V3 that are electrically insulated from the voltage V1 on the power supply unit 8 side and electrically insulated from each other. Inspection is performed by the inspection apparatuses A and B as the second inspection unit 5 using the voltage supplied from the floating power supply unit 9 as an operating voltage.

  Therefore, according to the circuit board inspection apparatus 1, unlike the circuit board inspection apparatus described in the background art, one second inspection section among all the second inspection sections provided for each electronic component that performs component inspection. (In the above example, the inspection apparatus C) can be supplied with the voltage V1 from the same power supply unit 8 as the control unit 6, the first inspection unit 4 and the like as an operating voltage. As a result of reducing the type of operating voltage for the second inspection unit to be generated by one type, the floating power source 9 has a floating power source as compared with the configuration in which the operating voltage for all the second inspection units is generated by the floating power source unit 9. The configuration of the unit 9 can be simply configured accordingly.

1 Circuit board inspection equipment
2 Fixture
3 Scanner
4 1st inspection department
5 Second inspection department
6 Control unit
8 Power supply
9 Floating power supply unit 21 Probe pin 51 Circuit board GP Conductive pattern group IC1, IC2, IC3 Integrated circuit
P Conductor pattern V1 voltage (first operating voltage)
V2, V3 voltage (second operating voltage)

Claims (1)

A plurality of probe pins to be brought into contact with the plurality of conductor patterns on the circuit board in which the plurality of conductor patterns are formed and the electronic components connected to any one of the plurality of conductor patterns are embedded are provided. With the fixtures
The insulation state between the inspection target parts having a pair of connection terminals and connected to the pair of connection terminals is set to a low potential on one connection terminal and a high potential on the other connection terminal. A first inspection unit for inspecting in a state;
The switch includes a plurality of changeover switches, and is disposed between the fixture and the first inspection unit in a state of being connected to the plurality of probe pins and the pair of connection terminals via wiring. Then, by controlling the on / off state of the change-over switch, a separated state in which all of the plurality of probe pins are disconnected from the pair of connection terminals and an arbitrary probe pin of the plurality of probe pins is disposed in the pair. A scanner that shifts to one of the connection states connected to the connection terminal,
A plurality of conductor pattern groups composed of all the conductor patterns connected in a chain via the electronic component and K independent conductor patterns not constituting the conductor pattern group (K is 3) As an inspection target part of the above integer), the scanner is controlled, a part of the K inspection target parts is set as the first group, and the inspection target of the first group By connecting a part to one of the pair of connection terminals, the part is connected to one of the low potential and the high potential, and among the K test target parts All the inspection target parts except the inspection target part of the first group are set as the second group, and the inspection target part of the second group is selected from the pair of connection terminals. While changing the combination of the parts to be inspected to set the connection processing to be connected to the other potential of the low potential and the high potential by connecting to the other connection terminal as the both groups, L times (L is log ₂ K or more and the closest integer to log ₂ K), and each time the connection process is executed, the control for the first inspection unit is executed and the inspection target connected to the pair of connection terminals A control unit that executes an insulation inspection process for inspecting an insulation state between the parts;
A circuit board inspection apparatus comprising: a first power supply for supplying a first operating voltage to the first inspection unit, the scanner, and the control unit;
A second inspection that is directly connected to the probe pins that are in contact with the conductor pattern that is connected to the electronic component that constitutes one conductor pattern group via a wiring, and that performs a component inspection on the electronic component And
A floating power supply for supplying a second operating voltage that is electrically insulated from the first working voltage and electrically insulated from each other;
The control unit performs the connection inspection process L times in a state in which one conductor pattern group of the plurality of conductor pattern groups is always connected to the low potential, and performs the insulation inspection process,
The second inspection unit that performs the component inspection on the electronic component that constitutes the one conductor pattern group connected to the low potential in the second inspection unit is configured to supply the first operating voltage from the power supply unit. The circuit board inspection apparatus that operates by receiving the supply of the second operation part, and all the second inspection parts other than the second inspection part operate by receiving the supply of the second operation voltage from the floating power supply part.

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