CN1399139A - Printed circuit board characteristic test device - Google Patents

Abstract

A printed circuit board characteristic testing apparatus comprising: a signal generating device, which provides a first signal; a sensor electrically connected to the signal generator for generating a mutual inductance with the inductance assembly, so that the first signal generates a second signal in response to the mutual inductance; a signal converter, electrically connected to the sensor, for converting the second signal into a DC signal and measuring a peak voltage from the DC signal; a signal processing device, which is electrically connected with the signal converter and sends a control signal corresponding to the magnitude relation between the peak voltage and a reference voltage; and a warning device, which is electrically connected with the signal processing device and is driven by the control signal, and changes the state of the signal processing device corresponding to the change of the state of the control signal, when the inductance component is short-circuited to cause that a relative voltage reference value measured by the signal processing device is not a preset voltage reference value, a warning signal is generated to judge whether the circuit of the inductance component is short-circuited.

Description

Printed circuit board characteristic test device

technical field

The invention relates to a printed circuit board characteristic testing device, in particular to a device for testing the short circuit of a multilayer printed circuit board with a planar transformer (Planar Transformer) structure.

Background technique

The early computers were huge, and a computer was as big as a room, because the previous computers were made of vacuum tubes, wires and transformers. Later, these bulky things were replaced by semiconductors and printed circuit boards. Now the computer is as small as You can carry it with you, thanks to the printed circuit board. Printed circuit boards are not only used for motherboards, but also adapter cards for computers or other household appliances must use this product. The printed circuit board etches the complex circuit copper wires between parts and parts on a board after careful and neat planning. As long as the parts are inserted on the board, the parts can interact with each other.

Therefore, a printed circuit board is sometimes a "sandwich" of several layers of circuits; for example, a planar transformer has as few as four layers and as many as seven layers. The more layers, not only the space occupied is smaller, but the noise of the circuit is also less . However, since these lines are directly etched on the printed circuit board, if the etching is incomplete, the lines of the printed circuit board may be cut off, thereby causing a short circuit phenomenon of the circuit.

In order to effectively control the production quality of the printed circuit board, generally after the etching of the printed circuit board is completed, it is necessary to measure whether there is a short circuit in the circuit of the printed circuit board. Please refer to Fig. 1, which is a schematic diagram of the short-circuit test of the printed circuit board 11 of the existing planar transformer. Since the planar transformer uses the mutual inductance between the coil and the magnetic field to change the inductance value and then achieve the purpose of changing the voltage value, therefore Before performing the short-circuit test of the printed circuit board 11 of the planar transformer, the two magnetic assemblies 121, 122 are respectively clipped on the upper and lower sides of the coil 13 of the printed circuit board, and the two magnetic assemblies 121, 122 and the The mutual inductance generated between the winding coils 13 of the printed circuit board is then connected to the two terminals 151 and 152 of the winding coils with an inductance-capacitance-resistance small meter (LCRminimeter) 14 to measure whether the inductance value is preset If the measured inductance value is not the preset inductance value, it can be known that the circuit on the printed circuit board of the planar transformer is a short circuit. However, the existing test method can only test the printed circuit board of a single planar transformer at a time by using a single instrument, which is not economical for the current mass-produced market. In addition, the magnetic component must be pre-clamped on the bottom of the printed circuit board before the measurement can be performed, which not only consumes time and energy, but also easily causes loss of parts and damage to the circuit board when plugging and unplugging the magnetic component. Increase unnecessary cost overhead.

Contents of the invention

The purpose of the present invention is to provide a printed circuit board characteristic testing device to measure whether there is a short circuit in the printed circuit board circuit.

In order to achieve the above object, the printed circuit board characteristic testing device according to one aspect of the present invention is suitable for the test of an inductive component circuit short circuit, and its characteristics are: a signal generating device, which provides a first signal; a sensor, an electrical connected to the signal generating device, used to generate a mutual inductance with the inductance component, so that the first signal corresponds to the mutual inductance to generate a second signal; a signal converter, electrically connected to the sensor , which converts the second signal into a DC signal, and can measure a peak voltage from the DC signal; a signal processing device, electrically connected to the signal converter, corresponding to the peak voltage and a reference voltage relationship, and send a control signal; and an alarm, electrically connected to the signal processing device, which is driven by the control signal, and changes its state corresponding to a state change of the control signal, when the When the inductance component is short-circuited and a relative voltage reference value measured by the signal processing device is not a predetermined voltage reference value, a warning signal is generated to determine whether the inductance component circuit is short-circuited.

According to the above idea, the signal generating device is an oscillator.

According to the above idea, the sensor is an inductor.

According to the above idea, the signal converter is a rectifier.

According to the above idea, the reference voltage is provided by a power supply.

According to the above idea, the signal processing device includes: a comparator electrically connected to the signal converter, which compares the peak voltage of the signal converter with the reference voltage, and outputs the relative voltage reference value ; and a voltage detector, electrically connected to the comparator, which detects whether the relative voltage reference value signal is the predetermined voltage reference value, and sends out the control signal.

According to the idea above, the warning device is a light emitting diode.

According to the idea above, the warning device is a buzzer.

In order to achieve the above object, a printed circuit board characteristic testing device according to another aspect of the present invention is suitable for the test of an inductive component circuit short circuit, and its characteristics are: a signal generating device, which provides a first signal; a sensor, electrically connected to the signal generating device, used to generate a mutual inductance with the inductance component, so that the first signal corresponds to the mutual inductance to generate a second signal; and a comparison device, electrically connected to the The sensor is used for comparing a peak voltage of the second signal with a reference voltage, and judging whether the circuit of the inductance component is short-circuited according to the magnitude relationship between the peak voltage and the reference voltage.

According to the above idea, the signal generating device is an oscillator.

According to the above idea, the sensor is an inductor.

According to the above idea, the reference voltage is provided by a power supply.

According to the above idea, the comparison device includes: a signal converter electrically connected to the sensor, which converts the second signal into a DC signal and provides the peak voltage; a comparator electrically connected to the A signal converter, used to compare the peak voltage with the reference voltage, and output a relative voltage reference value corresponding to the comparison value between the peak voltage and the reference voltage; a voltage discriminator, electrically connected to the comparison The device judges whether the relative voltage reference value signal is a predetermined voltage reference value, and sends out a control signal.

According to the above idea, the signal converter is a rectifier.

According to the above idea, the voltage discriminator is further electrically connected to an alarm, wherein the alarm is driven by the control signal, and changes its state corresponding to a state change of the control signal, when the inductance component When the short circuit causes the relative voltage reference value to be different from the predetermined voltage reference value, a warning signal is generated.

According to the idea above, the warning device is a light emitting diode.

According to the idea above, the warning device is a buzzer.

In order to better understand the purpose, features and advantages of the present invention, preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Description of drawings

Fig. 1 is a schematic diagram of a printed circuit board short-circuit test of an existing planar transformer.

FIG. 2 is a schematic functional block diagram of a printed circuit board short circuit test of a planar transformer according to a preferred embodiment of the present invention.

3 is a schematic circuit block diagram of a printed circuit board short-circuit test of a planar transformer according to a preferred embodiment of the present invention.

Detailed ways

Please refer to Fig. 2, it is the printed circuit board short circuit test functional block diagram of a preferred embodiment of the planar transformer of the present invention, is applicable to the test of an inductance assembly circuit short circuit, and its printed circuit board short circuit test device comprises a sensor 23 respectively It is connected in series between a signal generating device 22 and a signal processing device. The signal processing device is composed of a signal converter 24 , a comparator 25 and a voltage detector 26 .

The signal generating device 22 provides a first AC signal to the sensor 23, and when a mutual inductance is generated between the sensor 23 and the inductance component, the first AC signal will be generated corresponding to the mutual inductance a second AC signal. Then, the second AC signal is converted into a DC signal by the signal converter 24, and a peak voltage can be measured from the DC signal, and the peak voltage and a power supply 21 provided are input respectively. The reference voltage is sent to the comparator 25 to compare the peak voltage and the reference voltage, and output a relative voltage reference value corresponding to the magnitude relationship between the peak voltage and the reference voltage, and then use the voltage detector 26 to detect whether the relative voltage reference value signal is a predetermined voltage reference value, and send a control signal, the control signal is used to drive a warning device 27, that is, when the inductance component is short-circuited to cause the relative voltage When the reference value is not the predetermined voltage reference value, even if the warning device 27 generates a warning signal, wherein the warning device 27 can be a light emitting diode 271, 272 or a buzzer 273, or can be equipped with all The LEDs 271, 272 and the buzzer 273. For example: 1. Only the light-emitting diodes 271 and 272 are installed, and it can be set to turn on the light to display a warning signal when a short circuit occurs, and not turn on the light when it is normal. 2. If only the above-mentioned buzzer is installed, a warning sound will be issued when there is a short circuit. 3. The light emitting diodes 271, 272 and the buzzer 273 are installed at the same time, so as to be used in the situation of "needing to test multiple" printed circuit boards at the same time. Generally, only the light emitting diodes are used when observing whether there is a short circuit situation. The light signals shown in 271 and 272 must be monitored by a special person throughout the whole process, and staring at a specific item for a long time will cause eye fatigue, which may also cause "lose" situations. With the installation of the buzzer 273, the tester only needs to know whether there is a short circuit on the printed circuit board according to the warning sound of the buzzer 273, and then according to the position displayed by the light-emitting diodes 271 and 272 (Usually when measuring multiple printed circuit boards at the same time, each circuit board to be tested corresponds to a light-emitting diode) and then it can be known which printed circuit board is short-circuited. Therefore, using the LEDs 271, 272 and the buzzer 273 at the same time can not only reduce the waste of time and manpower, but also increase the working efficiency.

Please refer to FIG. 3 , which is a schematic circuit block diagram of a printed circuit board short-circuit test of a planar transformer according to a preferred embodiment of the present invention. Component numbers shown in FIG. 3 that are the same as those shown in FIG. 2 refer to the same components. In this embodiment, the signal converter 24 is composed of a rectifier 24, which is used to convert an AC signal into a DC signal, because the DC output voltage is greater than the effective value of the AC input voltage, so The DC signal has a more stable voltage value than the AC signal for detection. Preferably, the peak voltage measured in the DC signal and the reference voltage provided by the power supply 21 are input into the comparator 25, wherein the reference voltage is a default value , can be changed according to the inductance component to be tested. If the peak voltage is equal to the reference voltage V _ref , the comparator 25 outputs a voltage reference value “0”; otherwise, if the peak voltage is not equal to the reference voltage V _ref , the comparator 25 Outputting another voltage reference value "1", when the voltage detector 26 receives the voltage reference value transmitted from the comparator 25, if the accepted voltage reference value is 0, the voltage The detector 26 does not produce an action; on the contrary, when the voltage detector 26 receives the voltage reference value transmitted from the comparator 25, when the accepted voltage reference value is 1, the control is issued immediately. signal to make the warning device 27 generate the warning signal.

In addition, in another embodiment of the present invention, it can be set that when the voltage detector 26 receives the voltage reference value transmitted from the comparator 25, when the voltage detector 26 receives the voltage reference value transmitted from the comparator 25 When the voltage reference value is transmitted, if the accepted voltage reference value is 0, then send the control signal to make the warning device 27 generate the warning signal; otherwise, when the accepted voltage reference value is When 1, the voltage detector 26 does not operate.

The above-mentioned device can also be formed by connecting several identical circuits in series, and can measure multiple printed circuit boards at the same time to increase work efficiency. Therefore, the technology can be deduced by those who are familiar with the technology, so it will not be repeated here.

Claims (12)

1. a printed circuit board characteristic test set is applicable to the test of an Inductive component line short, it is characterized in that, comprising:

One signal generation apparatus, it provides one first signal;

One sensor is electrically connected on described signal generation apparatus, in order to producing a mutual inductance effect with described Inductive component, and the corresponding described mutual inductance of described first signal is done in order to produce a secondary signal;

One signal converter is electrically connected on described sensor, and it converts described secondary signal to a direct current signal, and can record a crest voltage by described direct current signal;

One signal processing apparatus is electrically connected on described signal converter, the magnitude relationship of a corresponding described crest voltage and a reference voltage, and send a control signal; And

One attention device, be electrically connected on described signal processing apparatus, it is driven by described control signal, and a state of corresponding described control signal changes and change its state, when cause the measured relative voltage reference value of described signal processing apparatus when described Inductive component short circuit be a non-predetermined voltage reference value, whether promptly produce an alarm signal, be short circuit to judge described Inductive component circuit.

2. printed circuit board test fixture as claimed in claim 1 is characterized in that, described signal generation apparatus is an oscillator.

3. printed circuit board test fixture as claimed in claim 1 is characterized in that, described sensor is an inductance.

4. printed circuit board test fixture as claimed in claim 1 is characterized in that, described signal converter is a rectifier.

5. printed circuit board test fixture as claimed in claim 1 is characterized in that, described reference voltage is provided by a power supply unit.

6. printed circuit board test fixture as claimed in claim 1 is characterized in that, described signal processing apparatus comprises:

One comparer is electrically connected on described signal converter, described crest voltage of its more described signal converter and described reference voltage, and export described relative voltage reference value; And

One voltage-level detector is electrically connected on described comparer, and whether it detects described relative voltage reference value signal is described predetermined voltage reference value, and sends described control signal.

7. printed circuit board test fixture as claimed in claim 1 is characterized in that, described attention device is a light emitting diode.

8. printed circuit board test fixture as claimed in claim 1 is characterized in that, described attention device is a hummer.

9. a printed circuit board characteristic test set is applicable to the test of an Inductive component line short, it is characterized in that, comprising:

One signal generation apparatus, it provides one first signal;

One sensor is electrically connected on described signal generation apparatus, in order to producing a mutual inductance effect with described Inductive component, and the corresponding described mutual inductance of described first signal is done in order to produce a secondary signal; And

One comparison means is electrically connected on described sensor, and in order to a crest voltage and a reference voltage of more described secondary signal, whether the magnitude relationship of corresponding described crest voltage and described reference voltage is short circuit to judge described Inductive component circuit.

10. printed circuit board test fixture as claimed in claim 9 is characterized in that, described signal generation apparatus can be an oscillator, described sensor is to be an inductance, and described reference voltage is provided by a power supply unit.

11. printed circuit board test fixture as claimed in claim 9 is characterized in that, described comparison means comprises:

One signal converter is electrically connected on described sensor, described secondary signal being converted to a direct current signal, and provides described crest voltage;

One comparer is electrically connected on described signal converter, and in order to more described crest voltage and described reference voltage, and the fiducial value of corresponding described crest voltage and described reference voltage is exported a relative voltage reference value;

One voltage checker is electrically connected on described comparer, and it is to differentiate whether described relative voltage reference value signal is a predetermined voltage reference value, and sends a control signal.

12. printed circuit board test fixture as claimed in claim 11, it is characterized in that, also be electrically connected an attention device behind the described voltage checker, wherein, described attention device is driven by described control signal, and a state of corresponding described control signal changes and change its state, when cause described relative voltage reference value when described Inductive component short circuit be non-described predetermined voltage reference value, promptly produces an alarm signal.

Images