Murata Manufacturing Co., Ltd.

Yoshikazu Takagi

Hirokazu Takashima

Hiroshi Ueoka

Yasunobu Yoneda

Takuji Nakagawa

Masaru Takahashi

Akira Nakamura

Yoshio Kawaguchi

Yasushi Ueno

Kazuaki Kawabata

Hideki Nakayama

Masayoshi Miyazaki

Nagato Omori

Toru Watanabe

Tatsuo Haratani

Fumiyuki Kobayashi

Teruo Yoshida

Hiroshi Sekidou

In a capacitor body of a multilayer capacitor, one second capacitor portion is sandwiched between two first capacitor portions. An ESR is controlled by setting a width of lead portions of third and fourth internal electrodes disposed in the second capacitor portion to be less than that of lead portions of first and second internal electrodes disposed in the first capacitor portions and by changing ratios between the first and second capacitor portions in the width of the lead portions and in the number of stacked internal electrodes. In the first capacitor portions, current paths from the internal electrodes to an external terminal electrode are widely distributed so that the first capacitor portions have a relatively low ESL, and accordingly, the ESL of the entire multilayer capacitor is reduced.

Multilayer capacitor having low equivalent series inductance and controlled equivalent series resistance

In a capacitor body, a single second capacitor unit is interposed between two first capacitor units. The width direction dimension of each of extended portions of first and second internal electrodes included in the first capacitor unit is larger than the width direction dimension of each of extended portions of third and fourth internal electrodes included in the second capacitor unit. The area of each of the respective portions of a first opposed portion of the first internal electrode and a second opposed portion of the second internal electrode, the respective portions being opposed to each other, is smaller than the area of each of respective portions of opposed portions of the third and fourth internal electrodes, the respective portions being opposed to each other. Thus, a multilayer capacitor has a characteristic that is a combination of a low-ESL characteristic of the first capacitor unit and a high-ESR characteristic of the second capacitor.

Multilayer capacitor having low ESL and easily controllable ESR

A multi-terminal monolithic ceramic capacitor arranged to reduce an equivalent series inductance and having an array structure is provided. A first same-polarity-connection conductor and a second same-polarity-connection conductor are provided inside a capacitor body so as to extend over at least two capacitors. The first same-polarity-connection conductor is electrically connected to a plurality of first external terminal electrodes, and the second same-polarity-connection conductor is connected to a plurality of second external terminal electrodes. In the monolithic ceramic capacitor which is mounted on a wiring substrate, the overall capacitance can be maintained even if an accident, such as cracking of a solder joint, occurs in one of the external terminal electrodes.

Monolithic ceramic capacitor

A monolithic ceramic capacitor includes a first same-polarity-electrode-connecting conductor and a second same-polarity-electrode-connecting conductor that are provided inside a ceramic laminate. The first same-polarity-electrode-connecting conductor is electrically connected to all of the first outer electrodes, and the second same-polarity-electrode-connecting conductor is electrically connected to all of the second outer electrodes. Preferably, a plurality of first same-polarity-electrode-connecting conductors and a plurality of second same-polarity-electrode-connecting conductors are successively disposed in the laminating direction inside the ceramic laminate.

In a multilayer capacitor including a capacitor body, first capacitor portions and a second capacitor portion are arranged in the direction of lamination. While a resonant frequency of the first capacitor portions is set to be greater than a resonant frequency of the second capacitor portion so that the first capacitor portions contribute to low ESL, an ESR per layer of the second capacitor portion is set to be greater than an ESR per layer of the first capacitor portions so that the second capacitor portion contributes to high ESR. Furthermore, a combined ESR of the first capacitor portions is set to be less than or greater than a combined ESR of the second capacitor portion.

Multilayer capacitor

In a multilayer capacitor including a capacitor body, first capacitor portions and a second capacitor portion are arranged in the direction of lamination. While a resonant frequency of the first capacitor portions is set to be greater than a resonant frequency of the second capacitor portion so that the first capacitor portions contribute to low impedance, an ESR per layer of the second capacitor portion is set to be greater than an ESR per layer of the first capacitor portions so that the second capacitor portion contributes to high ESR. Further, a combined ESR of the first capacitor portions is set to be substantially equal to a combined ESR of the second capacitor portion.

A multilayer capacitor includes first and second internal electrodes that are opposed to each other so as to generate an electrostatic capacitance and have a capacitance generating portion functioning to generate the electrostatic capacitance, terminal connecting portions connected to corresponding external terminal electrodes, and extended portions connecting the capacitance generating portion to the terminal connecting portions. The extended portions are narrower than the capacitance generating portion and the terminal connecting portion and are curved in the direction of their thickness so as to provide a longer effective length. The multi-terminal capacitor is capable of increasing an ESR without adding a separate additional element.

Multilayer capacitor and method of manufacturing the same

A monolithic capacitor includes a main capacitor unit having first capacitor portions and a second capacitor portion arranged in a direction of lamination, with the first capacitor portion located towards at least one end in the direction of lamination, so that the first capacitor portion is located closer to a mounting surface than the second capacitor portion. The number of pairs of third and fourth lead-out portions for third and fourth internal electrodes in the second capacitor portion is less than the number of pairs of first and second lead-out portions for first and second internal electrodes in the first capacitor portion, so that the first capacitor portion contributes to decreasing ESL while the second capacitor portion contributes to increasing ESR.

Monolithic capacitor and mounting structure thereof

A sorting method of monolithic ceramic capacitors in which high reliable sorting can be efficiently achieved based on measuring an insulating resistance involves first performing a burn-in process, which applies not less than double of the rated voltage at the maximum working temperature to a monolithic ceramic capacitor. Thereafter, a high temperature insulation resistance measuring process, which involves measuring an insulation resistance while applying not less than the rated voltage at a temperature of not less than 70&deg; C. to the monolithic ceramic capacitor, is performed so that monolithic ceramic capacitors having abnormal insulation resistances are eliminated. Preferably, the direction of applied voltage in the burn-in process agrees with the direction of applied voltage in the high temperature insulation resistance measuring process.

Method of sorting monolithic ceramic capacitors by measuring the insulation resistance thereof

In the temperature of 70-140 degrees C., the burn-in process of applying a voltage to monolithic ceramic capacitors so that the strength of the electric field applied between the internal electrodes opposing each other may be 7 30 kV/mm is performed. Subsequently, the insulation resistance of the monolithic ceramic capacitor is measured. The monolithic ceramic capacitors are sorted based on the insulation resistance measured during this insulation-resistance measurement process. In this case, it is sufficient to apply the burn-in process for 2-300 seconds.

Sorting method of monolithic ceramic capacitors based on insulation resistance

A ceramic electronic part includes at least one chip ceramic electronic part body having terminal electrodes and terminals provided on both sides. Each terminal is composed of a metal plate bent into a u shape. The outer face of a first leg of each bent terminal faces and is attached to a terminal electrode, and a second leg is attached to a substrate. The inner face of the bent terminal is provided with a solder-phobic surface not having affinity for solder, and the outer face of the bent terminal is provided with a solder-philic surface having high affinity for solder.

Ceramic electronic part and method for producing the same

A monolithic capacitor includes a plurality of monolithic ceramic capacitor elements provided with external electrodes at both ends thereof, solder layers arranged on the entire surfaces of the external electrodes of the monolithic ceramic capacitor elements, and metal terminals electrically connected to the external electrodes of the monolithic ceramic capacitor elements. The monolithic ceramic capacitor elements are joined to each other by the solder layers and are stacked on each other. The external electrodes of the monolithic ceramic capacitor elements are electrically connected to each other by the solder layers.

Monolithic capacitor

A ceramic electronic component includes a ceramic electronic component body having two end faces opposing each other, side faces connecting the two end faces, and terminal electrodes formed on each end face; and terminal members, each including a metal being soldered to one of the terminal electrodes. Each of the terminal electrodes includes a metal layer formed only on the end face, a conductive resin layer formed on the metal layer, the conductive resin layer including metal powder and resin, and a plating film on the conductive resin layer.

Ceramic electronic component

A ceramic electronic component includes at least one component body having two end faces opposing each other and side faces connecting the two end faces, and terminal electrodes formed on the component body. Each of the terminal electrodes extends from each end face to edge portions of each side face of the component body. Each of the terminal electrodes includes a metal layer formed on at least each end face of the component body, a conductive resin layer for covering at least portions of the side faces of the component body, and a metal plating film covering the outer surface of the terminal electrode. The conductive resin layer extends from the metal layer including the edge of the metal layer to the portions of the side faces, and includes a conductive resin containing metal powder and resin. The thickness of the conductive resin layer above the side faces is at least about 10 &mgr;m.

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Sabae, Japan

Yoshikazu Takagi