This application claims benefit of priority to Korean Patent Application No. 10-2022-0095485 filed on Aug. 1, 2022 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.
The present disclosure relates to an apparatus for measuring characteristics of a capacitor component.
Recently, as demand for electronic devices and electric devices (including vehicles) has rapidly increased according to the 4th industrial revolution, demand for capacitor components used in electronic devices/electric devices has also rapidly increased.
Therefore, the number of transactions of capacitor components between electronic device/electrical device manufacturers and capacitor component manufacturers has rapidly increased, and efficiency and convenience of measuring characteristics of capacitor components, which is important information in the capacitor component trading process, have become increasingly important.
In addition, as the services provided by electronic devices/electrical devices have become increasingly complex, performance required of electronic devices/electrical devices has gradually increased, accuracy/precision of the characteristics of capacitor components has also been increasingly required, and various types of capacitor components having different characteristics have been manufactured. As the types of capacitor components vary, difficulty (versatility) of securing accuracy/precision in characteristics of capacitor components may increase.
Consequently, performance of an apparatus for measuring characteristics of capacitor components may be evaluated based on the efficiency, convenience, accuracy, precision, and versatility of measuring characteristics of capacitor components, and the performance of the device is becoming increasingly important.
An aspect of the present disclosure may provide an apparatus for measuring characteristics of a capacitor component, capable of improving performance (at least one of efficiency, convenience, accuracy, precision, and versatility) for measurement of capacitor component characteristics.
According to an aspect of the present disclosure, an apparatus for measuring characteristics of a capacitor component may include a measurement terminal connected to a capacitor component, an inductor connected to the measurement terminal, and a controller generating characteristic information of the capacitor component based on LC resonance of the capacitor component and the inductor. The controller generates capacitance information of the capacitor component based on inductance, dependent on at least one of a resonant frequency and an amplitude of the LC resonance and the resonant frequency.
According to another aspect of the present disclosure, an apparatus for measuring characteristics of a capacitor component may include a measurement terminal connected to the capacitor component, an inductor connected to the measurement terminal, a controller generating characteristic information of the capacitor component based on the LC resonance of the capacitor component and the inductor, and a regulator feeding back the LC resonance so that the amplitude of the LC resonance approaches a target amplitude.
According to an aspect of the present disclosure, a method for measuring characteristics of a capacitor component may include obtaining LC resonance of the capacitor component and an inductor connected to the capacitor component in a measurement circuit; obtaining an amplitude of the LC resonance and obtaining a resonant frequency of the LC resonance; determining a range of a root mean square (RMS) voltage based on a measured value of the amplitude of the LC resonance; determining inductance corresponding to the resonant frequency of inductance characteristics corresponding to the range of the RMS voltage; and determining capacitance information based on the determined inductance.
According to an aspect of the present disclosure, an apparatus for measuring characteristics of a capacitor component may include a processor; and a non-transitory computer readable medium storing an algorithm, when executed by the processor, to cause the processor to: obtain LC resonance of the capacitor component and an inductor connected to the capacitor component in a measurement circuit, obtain an amplitude of the LC resonance and obtain a resonant frequency of the LC resonance, determine a range of a root mean square (RMS) voltage based on a measured value of the amplitude of the LC resonance, determine inductance corresponding to the resonant frequency of inductance characteristics corresponding to the range of the RMS voltage, and determine capacitance information based on the determined inductance.
The above and other aspects, features and other advantages of the present disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
Exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings.
Referring to
The measurement terminal 100 may be connected to the capacitor component CC. For example, the measurement terminal 100 may include a probe and may be connected to a cable. Accordingly, a user may measure the capacitor component CC by contacting the measurement terminal 100 to an external electrode of the capacitor component CC. Alternatively, the measurement terminal 100 may be in the form of a pin that is fixedly disposed on a printed circuit board (PCB) and exposed externally, and the user may measure the capacitor component CC by placing the capacitor component CC on the pin.
The inductor 200 may be electrically connected to the measurement terminal 100. For example, the inductor 200 may be a coil component and may be pre-mounted on a PCB. Alternatively, the inductor 200 may have a structure in which wires of a PCB are formed in a coil shape, instead of a coil component.
The controller 300 may be configured to generate characteristic information of the capacitor component CC based on LC resonance of the capacitor component CC and the inductor 200. Impedance in a combination structure of the capacitor component CC and the inductor 200 may vary according to frequency, and may be a minimum value (in the case of LC series resonance) or a maximum value (in the case of LC parallel resonance) at a resonant frequency of the LC resonance. In circuit theory, the square of the resonant frequency may be [1/{(inductance)*(capacitance)*4*(pi)*(pi)}]. The controller 300 may obtain all of the remaining information except for the capacitance, and may generate characteristic information corresponding to the capacitance based on the remaining information.
Therefore, since a structure required to obtain characteristic information corresponding to the capacitance based on the LC resonance may be simplified, the apparatus for measuring characteristics of a capacitor component according to an exemplary embodiment in the present disclosure may be advantageously implemented as a portable apparatus, like an apparatus 50out for measuring characteristics of a capacitor component illustrated in FIG. 7 and may be advantageous for improving efficiency/convenience, among performance of measuring characteristics of a capacitor component.
Since the minimum and maximum values of the impedance may be close to 0 and infinity, respectively, a change rate of impedance near the resonant frequency may be large according to a change in the resonant frequency. Therefore, compared to RC resonance, accuracy/precision of measuring characteristic information corresponding to capacitance based on the LC resonance may be relatively higher.
Therefore, the apparatus 50in for measuring characteristics of a capacitor component according to an exemplary embodiment in the present disclosure may be advantageous in increasing accuracy/precision among performance of measuring characteristics of a capacitor component.
The capacitor component CC may be a multilayer ceramic capacitor (MLCC), but is not limited thereto. The capacitance of the capacitor component CC may vary depending on the type of capacitor component CC. For example, the range of capacitance of the MLCC may be approximately 1 nF to 47 μF, which may be a wide range.
In general, as the efficiency/convenience and accuracy/precision of an apparatus for measuring capacitance is higher, the capacitance measurement range may be limited. Even if the apparatus provides a wide capacitance measurement range, accuracy/precision in a portion of the wide capacitance measurement range may be low.
Assuming that inductance is a constant, the resonant frequency of the LC resonance may vary as the capacitance of the capacitor component CC changes. Since the inductance of the actual inductor 200 may be slightly dependent on the resonant frequency or amplitude of the LC resonance due to the characteristics of a magnetic material or metal material of the inductor 200, the resonant frequency may primarily actually change depending on the change in capacitance of the capacitor component CC and may secondarily change according to a change in the inductance of the inductor 200 as well. In addition, due to physical characteristics of the LC resonance, the amplitude of LC resonance may also change according to a change in the resonant frequency of the LC resonance.
The controller 300 may generate capacitance information of the capacitor component CC based on the inductance and the resonant frequency dependent on at least one of the resonant frequency and the amplitude of the LC resonance. Therefore, since the controller 300 may calculate the capacitance using the inductance determined more accurately in consideration of the resonant frequency or amplitude of the LC resonance, the capacitance information of the capacitor component CC may be more accurately generated.
Accordingly, the apparatus 50in for measuring characteristics of a capacitor component according to an exemplary embodiment in the present disclosure is advantageous in increasing the efficiency/convenience and accuracy/precision of measurement performance, while stably securing measurement accuracy/precision in a wide capacitance range of the capacitor component CC.
Referring to
For example, the controller 300 may be configured as an embedded system, and may include a micro controller unit (MCU) or a processor, and a non-transitory computer readable medium storing an algorithm corresponding to the flowchart of
The horizontal axis and the vertical axis of
For example, referring to
Depending on the design, the controller may receive mode information (input) before LC resonance occurs (S301), and may determine inductance using inductance characteristics corresponding to an RMS voltage range determined according to the mode information. For example, the mode information may be generated by user input.
For example, as the capacitance of the capacitor component CC increases, an optimum value of the RMS voltage Vm of the LC resonance for measuring the characteristics of the capacitor component CC may decrease. For example, the optimum value may be 1 V when the capacitance of the capacitor component CC is 10 μF or less, and may be 0.5 V when the capacitance of the capacitor component CC exceeds 10 μF. A user may input the mode information according to the capacitance of the capacitor component CC.
For example, when the capacitor component CC is a multilayer ceramic capacitor (MLCC), the optimum value of the RMS voltage Vm of the LC resonance may vary depending on the characteristics (e.g., a difference in the composition ratio of a barium titanate composition) of a ferroelectric material of the capacitor component CC, and thus, the user may input the mode information according to the characteristics of the ferroelectric material of the capacitor component CC.
Referring to
The solid lines in
Referring to
Coefficients of the X variables of the first, second, third, fourth, and fifth polynomials corresponding to the first, second, third, fourth, and fifth inductance characteristics may be different from each other. Therefore, sensitivity of the resonant frequency of the inductance determination method may vary according to a resonant frequency range to which the resonant frequency of the LC resonance belongs, among the plurality of resonant frequency ranges.
Depending on the design, each of the first, second, third, fourth and fifth inductance characteristics may be simplified to an inductance constant. Accordingly, the controller 300 may generate capacitance information based on the inductance constant corresponding to the resonant frequency range to which the resonant frequency of the LC resonance belongs, among the plurality of resonant frequency ranges, and the resonant frequency of the LC resonance.
Referring to
Meanwhile, referring to
Accordingly, a change in the amplitude of the LC resonance due to a change in the capacitance of the capacitor component CC or a change in the resonant frequency of the LC resonance may be suppressed. Therefore, since one (the amplitude) of two variables (the resonant frequency and the amplitude) that may affect the inductance of the inductor 200 may be removed, the accuracy of the inductance of the inductor 200 may be effectively increased.
Accordingly, the apparatus 50in for measuring characteristics of a capacitor component according to an exemplary embodiment in the present disclosure may be advantageous in increasing the efficiency/convenience and accuracy/precision of measurement performance, while stably securing measurement accuracy/precision in a wide capacitance range of the capacitor component CC.
Referring to
The resonant voltage meter 510 may have an input terminal electrically connected to at least one of the measurement terminal 100 and the inductor 200, and may rectify an input signal. For example, the resonant voltage meter 510 may include a rectifier 510-1 and a measured value provider 510-2.
For example, the rectifier 510-1 may be a half-wave rectifier configured by a combination of at least some of an operational amplifier A51, a plurality of resistors R51 and R52, and a plurality of diodes D51 and D52. Depending on the design, a voltage follower 515 may accurately transfer a voltage of the output terminal of the rectifier 510-1 to a comparator and error amplifier 530+540, form circuit directionality and insulation properties, and may be configured by a combination of at least some of an operational amplifier B, a resistor R53, and capacitor C51. For example, the measured value provider 510-2 may provide an output voltage of the rectifier 510-1 or the voltage follower 515 to the controller 300 and may include an operational amplifier C.
The target voltage provider 520 may be configured to provide a target voltage corresponding to a target amplitude to the comparator and error amplifier 530+540. Depending on the design, the target voltage provider 520 may provide a target voltage determined according to a target voltage determination signal received from the controller 300. The target voltage determination signal may correspond to mode information input by the user.
The comparator and error amplifier 530+540 may be configured to amplify a difference voltage between the voltage of the output terminal of the resonant voltage meter 510 and the target voltage. Accordingly, the regulator 500 may provide feedback the LC resonance based on the difference voltage. For example, the comparator and error amplifier 530+540 may be formed by a combination of at least some of the operational amplifier A53, the plurality of resistors R54 and R55, and the plurality of capacitors C52, C53, and C54. For example, the voltage follower 545 may be connected to the output terminal of the comparator and error amplifier 530+540 to accurately transfer the output voltage to the resonant voltage amplitude converter 550, may form circuit directionality and insulation properties, and may include an operational amplifier D.
The resonant voltage amplitude converter 550 may adjust the amplitude of the output of the waveform converter 600 according to a gain determined based on the amplitude of the LC resonance and the target amplitude, and transfer an output of the waveform converter 600 having the adjusted amplitude to at least one of the measurement terminal 100 and inductor 200.
For example, the resonant voltage amplitude converter 550 may be configured by a combination of at least some of the operational amplifier A55 and the plurality of resistors R56 and R57. A bias voltage V37 may be provided to the plurality of resistors R56 and R57. A voltage between the plurality of resistors R56 and R57 may be transferred to a first input terminal of the operational amplifier A55 and may be used as a reference voltage. The output voltage of the waveform converter 600 may be transferred to a second input terminal of the operational amplifier A55, and the output voltage of the comparator and error amplifier 530+540 may be used as a power source for the operational amplifier A55. Accordingly, the voltage at the output terminal of the operational amplifier A55 may be a voltage amplified from the output voltage of the waveform converter 600 according to a gain based on the output voltage of the comparator and error amplifier 530+540.
The output terminal of the resonant voltage amplitude converter 550 may be connected to a DC blocking capacitor CO2 or a load resistor R58, and an output voltage of the resonant voltage amplitude converter 550 may be used for feedback on the LC resonance of the inductor 200 and the measurement terminal 100 to which the capacitor component is connected. Accordingly, the regulator 500 may use the output of the waveform converter 600 for feedback on the LC resonance.
Referring to
The waveform converter 600 may be configured by a combination of at least some of a plurality of operational amplifiers A61 and A62, a plurality of resistors R61, R62, R63, R64, R65, R66, R67, and R68, and a plurality of capacitors C61 and C62, and may be provided with power V38, and an input terminal of the waveform converter 600 may be connected to a DC block capacitor C01.
For example, the waveform converter 600 may convert a sinusoidal waveform of the LC resonance into a pulse waveform. The pulse waveform may be more effective in controlling the amplitude for feedback on the LC resonance in the regulator 500.
Referring to
The capacitance of the capacitor component CC may vary depending on an applied DC voltage. The apparatus 50in for measuring characteristics of a capacitor component may measure capacitance characteristics (DC-bias characteristics) according to a DC voltage applied to the capacitor component CC by measuring the capacitance of the capacitor component CC, while varying the DC voltage applied to the capacitor component CC.
In addition, since the apparatus 50in for measuring characteristics of a capacitor component may measure the capacitance based on the LC resonance, the influence of the DC voltage applied to the capacitor component CC on the capacitance measurement accuracy may be smaller than that of an RC resonance method. Therefore, the apparatus 50in for measuring characteristics of a capacitor component may accurately measure the DC-bias characteristics of the capacitor component CC.
For example, the DC voltage provider 400 may include at least some of a variable resistor 410, a voltage follower 420, a large-capacity capacitor 430, and a load resistor R42, and may be provided with power V39. The voltage provided from the variable resistor 410 to the voltage follower 420 may be determined based on a resistance values of the power V39 and the variable resistor 410, and may be applied accurately to the capacitor component CC by the voltage follower 420. The resistance value of the load resistor R42 may be determined based on load resistances R11 and R21 of the measurement terminal 100.
The large-capacity capacitor 430 may have a capacitance of 0.1 mF or more and may be electrically connected to the measurement terminal 100. Since the capacitance of the large-capacity capacitor 430 may be much larger than the capacitance of the capacitor component CC, an influence of a change in capacitance of the capacitor component CC on the DC voltage provided by the DC voltage provider 400 may decrease. Therefore, the apparatus 50in for measuring characteristics of a capacitor component may more accurately measure the DC-bias characteristics of the capacitor component CC. For example, the large-capacity capacitor 430 may be an electrolytic capacitor, may have a capacitance of 2.2 mF, and may be connected in series to the capacitor component CC.
Depending on the design, the apparatus 50in for measuring characteristics of a capacitor component may further include a DC voltage meter 450, and the DC voltage meter 450 may measure a DC voltage provided to the capacitor component CC by the DC voltage provider 400, and transfer a measurement result to the controller 300. The controller 300 may generate DC-bias characteristic information of the capacitor component CC based on the DC voltage measurement result and the measured capacitance information. For example, the DC voltage meter 450 may include a plurality of resistors R45 and R46, and resistance values of the plurality of resistors R45 and R46 may be determined based on the load resistors R11 and R21 of the measurement terminal 100.
The apparatus 50in for measuring characteristics of a capacitor component according to an exemplary embodiment in the present disclosure may include a boost DC-DC converter 390 boosting a voltage provided from a battery 380 or an external connection terminal 370. For example, the external connection terminal 370 may be a universal serial bus (USB) of another electronic device, and the battery 380 may be a secondary battery or an all-solid-state battery that may be used in a small electronic device and may be included in the apparatus 50in for measuring characteristics of a capacitor component.
Due to the boost DC-DC converter 390, a voltage provided from the battery 380 or the external connection terminal 370 may be a small voltage, such as 3.3V or 5V, and a DC voltage variable range (e.g., 0 V to 25 V) of the DC voltage provider 400 may be wide. Since the apparatus 50in for measuring characteristics of a capacitor component may receive a small voltage from the battery 380 or the external connection terminal 370, the apparatus 50in for measuring characteristics of a capacitor component be advantageously implemented as a portable device and may advantageously increase efficiency/convenience among performance of measuring characteristics of a capacitor component.
Referring to
The measurement terminal 100 may include a cable 100a connected to the inductor and a probe 100b connected to the cable 100a, and the user may bring the probe 100b into contact with the capacitor component to measure the characteristics of the capacitor component.
The jig 101 may be configured to be coupled to the capacitor component. Accordingly, the portability of the apparatus 50out for measuring characteristics of a capacitor component may be further improved.
The first input unit 301 may transmit a mode input signal to the controller according to a user's touch. For example, the controller may convert an RMS voltage of LC resonance into 1 V or 0.5 V by changing a target amplitude when a mode input signal is input.
The output unit 330 may display characteristic information of the capacitor component output by the controller and may include a display panel. For example, an upper left region of the output unit 330 may display resonant frequency information, a lower left region of the output unit 330 may display capacitance information, an upper right region of the output unit 330 may display RMS voltage information of the LC resonance, and a lower right region of the output unit 330 may display DC voltage information applied to the capacitor component.
The external connection terminal 370 may be connected to other electronic devices (e.g., computers, portable terminals, home appliances, etc.) to receive power from the other electronic devices. For example, the external connection terminal 370 may be USB Type-C, and supplied power may be stored in a battery in the apparatus 50out for measuring characteristics of a capacitor component or may be boosted by a boost DC-DC converter.
The second input unit 401 may transmit a variable resistor resistance value adjustment signal to the controller according to a user's rotation. For example, the controller may adjust the resistance value of the variable resistor in the DC voltage provider when a variable resistor resistance value adjustment signal is input. Accordingly, the DC voltage applied to the capacitor component may be adjusted.
The apparatus for measuring characteristics of a capacitor component according to the present disclosure may improve performance (at least one of efficiency, convenience, accuracy, precision, and versatility) of measuring characteristics of a capacitor component.
While exemplary embodiments have been illustrated and described above, it will be apparent to those skilled in the art that modifications and variations could be made without departing from the scope of the present disclosure as defined by the appended claims.
Number | Date | Country | Kind |
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10-2022-0095485 | Aug 2022 | KR | national |