Circuit board test circuit and device

Abstract

The utility model provides a circuit board test circuit and device. The circuit board test circuit comprises a switch module; the input end of the switch module is used for being connected with a power supply; the output end of the switch module is used for being connected with the power supply input end of a circuit board to be tested. The detection end of the switch module is used for abutting against the test point of the circuit board to be tested, and when the detection end of the switch module abuts against the test point of the circuit board to be tested, the input end and the output end of the switch module are communicated. The circuit board to be detected can start detection work only when the circuit board to be detected is in contact with the detection end of the circuit board test circuit, that is, the circuit board to be detected can start detection work only when the circuit board to be detected is accurately placed at the corresponding position, and if the circuit board to be detected is only in place and the position of the test point does not correspond to the position of the detection end, the circuit board to be detected can be detected. If so, the circuit board test circuit cannot supply power to the to-be-tested circuit board, so that the test cannot be performed, and the in-place state of the to-be-tested circuit board can be accurately detected and detected.

Description

Technical Field

[0001] The utility model relates to the technical field of equipment failure prediction, in particular to a circuit board testing circuit and a device. Background Art

[0002] Circuit board products require pre-production testing. However, improper operation during the testing process can lead to a series of problems with the circuit board being tested. Existing testing solutions typically utilize a presence detection device composed of a light-emitting diode (LED) and a photosensitive element. The LEDs reflect the presence and absence of the device under test as two different light intensities. The photosensitive element then uses these two different light intensities to determine whether the device is in place, thus achieving automatic detection of the device's presence.

[0003] However, because LEDs need to be lit for a long time, their lifespan is significantly shortened, which can easily lead to failure of the in-place detection device. Furthermore, this technology only detects the device's in-place status, but cannot accurately determine whether the device is in place. Furthermore, in strong light conditions, the light sensor can easily misjudge the device, causing the in-place detection device to fail. Furthermore, the need to judge the light sensor's feedback data makes subsequent maintenance difficult. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a circuit board testing circuit and device, which can accurately detect the in-place state of the circuit board to be tested.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A circuit board test circuit includes a switch module; an input end of the switch module is used to connect to a power supply; an output end of the switch module is used to connect to a power supply input end of a circuit board to be tested; a detection end of the switch module is used to abut against a test point of the circuit board to be tested, and when abutting against the test point of the circuit board to be tested, the input end and the output end of the switch module are connected.

[0007] Furthermore, the switch module includes a first resistor and a PMOS tube; the source of the PMOS tube is connected to one end of the first resistor and serves as the input end of the switch module; the gate of the PMOS tube is connected to the other end of the first resistor and serves as the detection end of the switch module; the drain of the PMOS tube serves as the output end of the switch module.

[0008] Furthermore, it also includes an input voltage filter capacitor component; one end of the input voltage filter capacitor component is connected to the source of the PMOS tube; and the other end of the input voltage filter capacitor component is grounded.

[0009] Furthermore, the input voltage filter capacitor assembly includes an electrolytic capacitor; the positive electrode of the electrolytic capacitor is connected to the source electrode of the PMOS tube; and the negative electrode of the electrolytic capacitor is grounded.

[0010] Furthermore, it also includes an output voltage filter capacitor component: one end of the output voltage filter capacitor component is connected to the drain of the PMOS tube; the other end of the output voltage filter capacitor component is grounded.

[0011] Furthermore, it also includes a bidirectional trigger diode; one end of the bidirectional trigger diode is connected to the gate of the PMOS tube; and the other end of the bidirectional trigger diode is grounded.

[0012] Furthermore, it also includes a second resistor; one end of the second resistor is connected to the gate of the PMOS tube; the other end of the second resistor is connected to one end of the bidirectional trigger diode and serves as the detection end of the switch module.

[0013] In order to solve the above technical problems, another technical solution adopted by the present invention is:

[0014] A circuit board testing device comprises a tray, a needle bed plate and the above-mentioned circuit board testing circuit; the tray is arranged opposite to the needle bed plate; the tray is used to place the circuit board to be tested, and the test point of the circuit board to be tested is facing the needle bed plate; the circuit board testing circuit is arranged on the side of the needle bed plate away from the tray, and the detection end of the circuit board testing circuit is connected to the top pin of the needle bed plate.

[0015] Furthermore, the needle bed plate is arranged below the tray; and the ejector pins of the needle bed plate pass through the tray.

[0016] Furthermore, it also includes a pressing assembly; the pressing assembly can be raised and lowered and arranged on a side of the tray away from the needle bed plate.

[0017] The beneficial effects of the present invention are as follows: by arranging a switch module in the circuit board test circuit, connecting the input end of the switch module to the power supply, and connecting the output end to the power supply input end of the circuit board to be tested, and by connecting the input end and the output end when the detection end abuts the test point of the circuit board to be tested, power is supplied to the circuit board to be tested, so that the circuit board to be tested can only start the detection work when the circuit board to be tested is in contact with the detection end of the circuit board test circuit, that is, the detection work can only start when the circuit board to be tested is accurately placed in the corresponding position; if it is just in place but the position of the test point does not correspond to the position of the detection end, the circuit board test circuit cannot power the circuit board to be tested, and thus cannot perform the test, thereby accurately detecting the in-place state of the circuit board to be tested and performing the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a connection diagram of a circuit board test circuit in an embodiment of the present utility model;

[0019] Figure 2 This is a schematic flowchart of the steps of a circuit board testing device in an embodiment of the present invention;

[0020] Description of labels:

[0021] R1, first resistor; R2, second resistor; Q1, PMOS tube; D1, bidirectional trigger diode; CT1, electrolytic capacitor. DETAILED DESCRIPTION

[0022] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following description is given in conjunction with the embodiments and the accompanying drawings.

[0023] Please refer to Figure 1 A circuit board test circuit includes a switch module; the input end of the switch module is used to connect to a power supply; the output end of the switch module is used to connect to the power supply input end of the circuit board to be tested; the detection end of the switch module is used to abut against the test point of the circuit board to be tested, and when abutting against the test point of the circuit board to be tested, the input end and the output end of the switch module are connected.

[0024] From the above description, it can be seen that the beneficial effect of the present invention is that: by arranging a switch module in the circuit board test circuit, connecting the input end of the switch module to the power supply, and connecting the output end to the power supply input end of the circuit board to be tested, and by connecting the input end and the output end when the detection end abuts the test point of the circuit board to be tested, power is supplied to the circuit board to be tested, so that the circuit board to be tested can only start the detection work when the circuit board to be tested is in contact with the detection end of the circuit board test circuit, that is, the detection work can only start when the circuit board to be tested is accurately placed in the corresponding position. If it is just in place and the test point position does not correspond to the detection end position, the circuit board test circuit cannot power the circuit board to be tested, and thus cannot perform testing, so that the in-place state of the circuit board to be tested can be accurately detected and detected.

[0025] Furthermore, the switch module includes a first resistor and a PMOS tube; the source of the PMOS tube is connected to one end of the first resistor and serves as the input end of the switch module; the gate of the PMOS tube is connected to the other end of the first resistor and serves as the detection end of the switch module; the drain of the PMOS tube serves as the output end of the switch module.

[0026] From the above description, it can be seen that by setting a first resistor and a PMOS tube to form a switch module, and under the action of the first resistor, the gate of the PMOS tube is set to a high level by default and cannot be turned on. When the gate of the PMOS tube is connected to the test point of the circuit board to be tested, the gate of the PMOS tube is pulled low, thereby turning on the source and drain of the PMOS tube, thereby realizing power supply and testing of the circuit board to be tested.

[0027] Furthermore, it also includes an input voltage filter capacitor component; one end of the input voltage filter capacitor component is connected to the source of the PMOS tube; and the other end of the input voltage filter capacitor component is grounded.

[0028] As can be seen from the above description, by providing an input voltage filter capacitor component at the input end of the switch module, the input voltage can be filtered, thereby providing a stable voltage for the circuit board to be tested.

[0029] Furthermore, the input voltage filter capacitor assembly includes an electrolytic capacitor; the positive electrode of the electrolytic capacitor is connected to the source electrode of the PMOS tube; and the negative electrode of the electrolytic capacitor is grounded.

[0030] As can be seen from the above description, using an electrolytic capacitor as an input voltage filter capacitor component can effectively charge and discharge the capacitor and eliminate the AC component in the input voltage.

[0031] Furthermore, it also includes an output voltage filter capacitor component: one end of the output voltage filter capacitor component is connected to the drain of the PMOS tube; the other end of the output voltage filter capacitor component is grounded.

[0032] As can be seen from the above description, by providing an output voltage filter capacitor component at the output end of the switch module, the output voltage can be filtered, thereby providing a more stable voltage for the circuit board to be tested.

[0033] Furthermore, it also includes a bidirectional trigger diode; one end of the bidirectional trigger diode is connected to the gate of the PMOS tube; and the other end of the bidirectional trigger diode is grounded.

[0034] As can be seen from the above description, by providing a bidirectional trigger diode at the detection end of the switch module, static electricity generated by the contact between the ejector pin at the detection end and the circuit board to be tested can be eliminated.

[0035] Furthermore, it also includes a second resistor; one end of the second resistor is connected to the gate of the PMOS tube; the other end of the second resistor is connected to one end of the bidirectional trigger diode and serves as the detection end of the switch module.

[0036] From the above description, it can be seen that by setting a second resistor between the gate of the PMOS tube and the detection terminal, the high-frequency oscillation signal generated by the detection terminal can be eliminated, thereby avoiding false triggering of the PMOS tube gate due to the high-frequency oscillation signal.

[0037] A circuit board testing device comprises a tray, a needle bed plate and the above-mentioned circuit board testing circuit; the tray is arranged opposite to the needle bed plate; the tray is used to place the circuit board to be tested, and the test point of the circuit board to be tested is facing the needle bed plate; the circuit board testing circuit is arranged on the side of the needle bed plate away from the tray, and the detection end of the circuit board testing circuit is connected to the top pin of the needle bed plate.

[0038] From the above description, it can be seen that by placing the circuit board to be tested at the specified position of the tray, the detection on the needle bed board is aligned with the test point of the circuit board to be tested, so that the switch module of the circuit board test circuit is turned on to power the circuit board to be tested and complete the corresponding test.

[0039] Furthermore, the needle bed plate is arranged below the tray; and the ejector pins of the needle bed plate pass through the tray.

[0040] From the above description, it can be seen that by setting the needle bed plate under the tray and the circuit board test circuit on the side of the needle bed plate away from the tray, that is, the needle bed plate and the circuit board test circuit are set at the bottom of the device, there is no need to operate the needle bed plate and the circuit board test circuit during the test process, which improves the stability of the device during the test process and facilitates the installation of the device.

[0041] Furthermore, it also includes a pressing assembly; the pressing assembly can be raised and lowered and arranged on a side of the tray away from the needle bed plate.

[0042] From the above description, it can be seen that by arranging a liftable pressing assembly above the tray, the circuit board to be tested can be effectively contacted with the ejector pins by pressing down the pressing assembly, thereby avoiding the problem that the ejector pins cannot form effective contact with the test points of the circuit board to be tested, resulting in the inability to perform testing.

[0043] The circuit board testing circuit and device provided by the utility model are applied to the circuit board testing scenario, so that the circuit board under test can be tested only when it is accurately placed. The following is an explanation of the specific implementation method:

[0044] Example 1

[0045] A circuit board test circuit includes a switch module; an input end of the switch module is used to connect to a power supply; an output end of the switch module is used to connect to a power supply input end of a circuit board to be tested; a detection end of the switch module is used to abut against a test point of the circuit board to be tested, and when abutting against the test point of the circuit board to be tested, the input end and the output end of the switch module are connected.

[0046] Please refer to Figure 1 In one optional embodiment, the switch module includes a first resistor R1 and a PMOS transistor Q1; the source of the PMOS transistor Q1 is connected to one end of the first resistor R1 and serves as the input terminal (VIN) of the switch module; the gate of the PMOS transistor Q1 is connected to the other end of the first resistor R1 and serves as the detection terminal of the switch module; and the drain of the PMOS transistor Q1 serves as the output terminal (VOUT) of the switch module. In other optional embodiments, the switch module can also be implemented using other devices with a gating function, such as an NMOS transistor, a transistor, etc.

[0047] In this embodiment, the PMOS transistor Q1 is used as an example for description, wherein the switch module further includes an input voltage filter capacitor component, an output voltage filter capacitor component, a bidirectional trigger diode D1, and a second resistor R2; one end of the input voltage filter capacitor component is connected to the source of the PMOS transistor Q1; the other end of the input voltage filter capacitor component is grounded. Specifically, the input voltage filter capacitor component includes an electrolytic capacitor CT1 and a capacitor C205; the positive electrode of the electrolytic capacitor CT1 is connected to the source of the PMOS transistor Q1; the negative electrode of the electrolytic capacitor CT1 is grounded; and the capacitor C205 is connected in parallel with the electrolytic capacitor CT1.

[0048] One end of the output voltage filter capacitor assembly is connected to the drain of the PMOS transistor Q1; the other end of the output voltage filter capacitor assembly is grounded. Specifically, the output voltage filter capacitor assembly includes capacitors C206 and C207 connected in parallel. The number and type of capacitors in the input voltage filter capacitor assembly and the output voltage filter capacitor assembly can be selected according to actual conditions.

[0049] One end of the bidirectional trigger diode D1 is connected to the gate of the PMOS transistor Q1; the other end of the bidirectional trigger diode D1 is grounded. One end of the second resistor R2 is connected to the gate of the PMOS transistor Q1; the other end of the second resistor R2 is connected to one end of the bidirectional trigger diode D1 and serves as the detection terminal (TP30) of the switch module.

[0050] The specific principles of the above circuit board test circuit are as follows:

[0051] When the detection terminal (TP30) of the switch module contacts the test point of the circuit board under test (the test point is the digital ground), the second resistor R2 transmits a low-level signal to the gate of the PMOS transistor Q1, causing the gate voltage of the PMOS transistor Q1 to be pulled down. At this time, the source and drain of the PMOS transistor Q1 are connected, and the input current of the switch module is divided by the first resistor R1 and the second resistor R2 to supply power to the circuit board under test.

[0052] When the switch module's detection terminal (TP30) isn't in contact with a test point on the circuit board under test, the second resistor R2 causes the gate of PMOS transistor Q1 to default to a high level, disconnecting the source and drain of PMOS transistor Q1 and preventing power from being supplied to the circuit board under test. This means the circuit board under test doesn't need to be connected to a wired power source. The circuit board test circuit is connected to a wired power source (DC24V). When the switch module's detection terminal contacts a test point on the circuit board under test, power is supplied to the circuit board.

[0053] Example 2

[0054] A circuit board testing device comprises a tray, a needle bed plate, a pressing assembly, and the circuit board test circuit described in Example 1; the tray and the needle bed plate are arranged opposite each other; the tray is used to place the circuit board to be tested, with the test points of the circuit board to be tested facing the needle bed plate; the circuit board test circuit is arranged on the side of the needle bed plate away from the tray, and the detection end of the circuit board test circuit is connected to the ejector pins of the needle bed plate. The needle bed plate is arranged below the tray; the ejector pins of the needle bed plate extend through the tray; and the pressing assembly is arranged on the side of the tray away from the needle bed plate, which can be raised and lowered.

[0055] Please refer to Figure 2 The specific usage steps of the above-mentioned circuit board testing device are as follows: after placing the circuit board to be tested on the tray, control the pressure rod assembly to press down so that the circuit board to be tested contacts the ejector pins of the needle bed plate; when the test points of the circuit board to be tested contact the ejector pins of the needle bed plate, the circuit board testing circuit supplies power to the circuit board to be tested; when the test points of the circuit board to be tested do not contact the ejector pins of the needle bed plate, it is necessary to control the pressure rod assembly to lift and adjust the position of the circuit board to be tested until the test points of the circuit board to be tested contact the ejector pins of the needle bed plate.

[0056] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent transformations made using the contents of the description and drawings of the present invention, or directly or indirectly applied in the relevant technical field, are also included in the patent protection scope of the present invention.

Claims

1. A circuit board test circuit, characterized in that: Including switch module; The input end of the switch module is used to connect to a power source; The output end of the switch module is used to connect to the power supply input end of the circuit board to be tested; The detection end of the switch module is used to abut against the test point of the circuit board to be tested, and when abutting against the test point of the circuit board to be tested, the input end and the output end of the switch module are connected.

2. A circuit board test circuit according to claim 1, characterized in that: The switch module includes a first resistor and a PMOS tube; The source of the PMOS tube is connected to one end of the first resistor and serves as the input end of the switch module; The gate of the PMOS tube is connected to the other end of the first resistor and serves as a detection end of the switch module; The drain of the PMOS tube serves as the output end of the switch module.

3. A circuit board test circuit according to claim 2, characterized in that: Also included is an input voltage filter capacitor assembly; One end of the input voltage filter capacitor component is connected to the source of the PMOS tube; The other end of the input voltage filter capacitor component is grounded.

4. A circuit board test circuit according to claim 3, characterized in that: The input voltage filter capacitor assembly includes an electrolytic capacitor; The positive electrode of the electrolytic capacitor is connected to the source electrode of the PMOS tube; The negative electrode of the electrolytic capacitor is grounded.

5. A circuit board testing circuit according to claim 2, characterized in that: Also included are the output voltage filter capacitor components: One end of the output voltage filter capacitor component is connected to the drain of the PMOS tube; The other end of the output voltage filter capacitor component is grounded.

6. A circuit board testing circuit according to claim 2, characterized in that: Also includes bidirectional trigger diodes; One end of the bidirectional trigger diode is connected to the gate of the PMOS tube; The other end of the bidirectional trigger diode is grounded.

7. A circuit board testing circuit according to claim 6, characterized in that: Also including a second resistor; One end of the second resistor is connected to the gate of the PMOS tube; The other end of the second resistor is connected to one end of the bidirectional trigger diode and serves as a detection end of the switch module.

8. A circuit board testing device, characterized in that: comprising a tray, a bed of nails plate and a circuit board test circuit as claimed in any one of claims 1 to 7; The tray is arranged opposite to the needle bed plate; The tray is used to place the circuit board to be tested, and the test point of the circuit board to be tested is directed toward the needle bed plate; The circuit board test circuit is arranged on a side of the needle bed plate away from the tray, and a detection end of the circuit board test circuit is connected to the ejector pin of the needle bed plate.

9. A circuit board testing device according to claim 8, characterized in that: The needle bed plate is arranged below the tray; The ejector pins of the needle bed plate pass through the tray.

10. A circuit board testing device according to claim 9, characterized in that: Also included are press-fit components; The pressing assembly can be lifted and lowered and is arranged on a side of the tray away from the needle bed plate.

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