Matching module

A matching module includes an inductor pattern including a first inductor pattern and a second inductor pattern, each respectively provided in a spiral shape, and a connection pattern connecting the first inductor pattern and the second inductor pattern and provided in a central region of a dielectric sheet, and a capacitor pattern provided in an edge region of the dielectric sheet and configured to form mutual capacitance with the inductor pattern, wherein rotational directions of the first inductor pattern and the second inductor pattern that are provided in the spiral shape are the same.

CROSS-REFERENCE TO RELATED APPLICATIONS

BACKGROUND

The following description relates to a matching module.

2. Description of Related Art

With the recent development of mobile communication systems, mobile devices are rapidly spreading. Accordingly, demand for miniaturization and high performance in a large number of electronic parts used in mobile devices is increasing. Among such electronic parts, a duplexer is responsible for functions of separating a transmitting signal and a receiving signal. and simultaneously extracting only a signal of a necessary frequency band. A duplexer is an essential component in a transmitting/receiving communication method such as an analog or Code Division Multiple Access (CDMA) method.

Such a duplexer includes a transmitting filter, a receiving filter, and a matching module for separating a transmitting signal of the transmitting filter and a receiving signal of the receiving filter. The matching module separates the transmitting signal and the receiving signal to minimize interference between the transmitting signal and the receiving signal. The matching module is configured to minimize an influence on electrical characteristics of the transmitting filter and the receiving filter. For example, the matching module may be represented as an equivalent circuit in which a capacitor-inductor-capacitor is connected in a form of a pi (π) filter. In order to change a phase while maintaining a matched frequency band of the matching module, capacitances of two capacitors may need to be the same. However, there may be a problem in that the capacitances of the two capacitors are possibly different due to a parasitic capacitance incidentally generated in the matching module.

SUMMARY

In one general aspect, a matching module includes an inductor pattern including a first inductor pattern and a second inductor pattern, each respectively provided in a spiral shape, and a connection pattern connecting the first inductor pattern and the second inductor pattern and provided in a central region of a dielectric sheet, and a capacitor pattern provided in an edge region of the dielectric sheet and configured to form mutual capacitance with the inductor pattern, wherein rotational directions of the first inductor pattern and the second inductor pattern have a same rotational direction.

The first inductor pattern and the second inductor pattern may be provided symmetrical with respect to each other.

The first inductor pattern and the second inductor pattern may be rotationally symmetrical with respect to each other.

A direction of a signal path of a pattern arranged in parallel, adjacent to the connection pattern in an outermost loop of each of the first inductor pattern and the second inductor pattern, may be a same direction as a direction of a signal path of the connection pattern.

The first inductor pattern, the second inductor pattern, and the connection pattern may be formed to be continuous.

The mutual capacitance may be generated between the capacitor pattern and an outermost loop of each of the first inductor pattern and the second inductor pattern.

A terminal disposed in a center of the first inductor pattern provided in the spiral shape may be connected to either one or both of a transmitting filter and an antenna, and a terminal disposed in a center of the second inductor pattern provided in the spiral shape may be connected to a receiving filter.

The capacitor pattern may be connected to a ground.

The capacitor pattern may be insulated from the first inductor pattern, the second inductor pattern, and the connection pattern.

In another general aspect, a matching module includes an inductor connected between a transmitting terminal and a receiving terminal, a first capacitor connected between the transmitting terminal and a ground, and a second capacitor connected between the receiving terminal and the ground, wherein the inductor is formed using an inductor pattern comprising a first inductor pattern and a second inductor pattern, each respectively provided in a spiral shape, and a connection pattern connecting the first inductor pattern and the second inductor pattern, and wherein the first inductor pattern and the second inductor pattern have a same rotational direction.

The first capacitor and the second capacitor may be insulated from the inductor pattern and may be formed using a capacitor pattern that forms mutual capacitance with the inductor pattern.

The first inductor pattern and the second inductor pattern may be symmetrical with respect to each other.

The first inductor pattern and the second inductor pattern may be rotationally symmetrical with respect to each other.

A direction of a signal path of a pattern arranged in parallel, adjacent to the connection pattern in an outermost loop of each of the first inductor pattern and the second inductor pattern may be a same direction as a direction of a signal path of the connection pattern.

The first inductor pattern, the second inductor pattern, and the connection pattern may be formed to be continuous.

The mutual capacitance may be generated between the capacitor pattern and an outermost loop of each of the first inductor pattern and the second inductor pattern.

The capacitor pattern may be connected to a ground.

The capacitor pattern may be insulated from the first inductor pattern, the second inductor pattern, and the connection pattern.

DETAILED DESCRIPTION

Hereinafter, examples will be described in further detail with reference to the accompanying drawings.

An aspect of the present disclosure provides a matching module in which at least two capacitors have the same capacitance.

FIG. 1is a block diagram of a duplexer according to an example.

Referring to the example ofFIG. 1, a duplexer10, according to such an example, includes a matching module100, a transmitting filter200, and a receiving filter300. The matching module100is connected to an antenna AT through a first port P1, to the transmitting filter200through a second port P2, and to the receiving filter300through a third port P3.

The transmitting filter200transmits a transmitting signal filtered through the antenna AT. The receiving filter300filters a receiving signal received through the antenna AT. For example, the transmitting filter200and the receiving filter300may include a thin film bulk acoustic resonator capable of realizing a high quality factor. A thin film bulk acoustic resonator is a device formed of piezoelectric material sandwiched between two electrodes, and has resonance properties that allow such a resonator to act as a filter. In such an example, the matching module100minimizes interference between the transmitting signal and the receiving signal by separating the transmitting signal and the receiving signal.

FIG. 2is an equivalent circuit diagram of a matching module according to an example.

Referring to the example ofFIG. 2, an equivalent circuit of the matching module100includes one inductor L and at least two capacitors C1and C2. For example, the equivalent circuit of the matching module100is a circuit in which the one inductor L and the two capacitors C1and C2are connected in the form of a pi (π) filter. Specifically, in such an example, the inductor L is connected between a transmitting terminal Pa and a receiving terminal Pb. Additionally, the first capacitor C1of the two capacitors C1and C2is disposed between the transmitting terminal Pa and a ground, and the second capacitor C2is disposed between the receiving terminal Pb and a ground. Likewise, the transmitting terminal Pa is connected to the first port P1and the second port P2ofFIG. 1and the receiving terminal Pb is connected to the third port P3ofFIG. 1.

In one example, the capacitances of the first capacitor C1and the second capacitor C2have the same capacitance in order for the matching module100to change a phase while maintaining a matched region. However, due to a parasitic capacitance incidentally generated in the matching module100, the capacitances of the first and second capacitors C1and C2are possibly different from each other.

FIG. 3is an assembled perspective view of a matching module according to an example.FIG. 4is an exploded perspective view of a matching module according to an example. Referring to the examples ofFIGS. 3 and 4, the matching module100includes a stack dielectric sheet110, and a ground portion120disposed at upper and lower portions of the stack dielectric sheet110.

The stack dielectric sheet110includes at least two dielectric sheets. For example, the dielectric sheet is generally implemented as a rectangular dielectric sheet of a ceramic material or alternatively is implemented by using different shapes and materials. As an example, as shown in the example ofFIG. 3, the stack dielectric sheet110includes a first dielectric sheet111and a second dielectric sheet112.

The first dielectric sheet111includes at least one pattern used to implement the inductor L and the at least two capacitors C1, C2of the example ofFIG. 2.

FIG. 5is a top view of a first dielectric sheet according to an example.

Referring to the examples ofFIGS. 3 to 5, the first dielectric sheet111includes a first inductor pattern111a, a second inductor pattern111b, a connection pattern111c, and a capacitor pattern111d.

The first inductor pattern111a, the second inductor pattern111band the connection pattern111ccorresponding to inductor patterns are electrically connected to first through third ports P1, P2, P3respectively corresponding to an antenna port, a transmitting port, and a receiving port through vias. In the example ofFIG. 5, the first inductor pattern111ais connected to the first port P1formed in a first ground portion121and the second port P2formed in a second ground portion122through the via. The second inductor pattern111bis connected to the third port P3formed in the second ground portion122.

In such an example, each of the first inductor pattern111aand the second inductor pattern111bis formed by a conductive pattern in a spiral shape. For example, the first inductor pattern111aand the second inductor pattern111bprovided in the spiral shape may have the same rotational direction.

Thus, according to the example ofFIG. 5, the first inductor pattern111ais provided in the spiral shape in relation to a first terminal T1and terminates at a second terminal T2. In this manner, the first terminal T1corresponds to the transmitting terminal Pa of the example ofFIG. 2.

In an example, the second inductor pattern111bis provided in the spiral shape in relation to a third terminal T3and terminates at a fourth terminal T4. In this manner, the third terminal T3corresponds to the receiving terminal Pb of the example ofFIG. 2.

The connection pattern111cis provided between the second terminal T2and the fourth terminal T4and connects the first inductor pattern111aand the second inductor pattern111b. For example, the connection pattern111cmay be formed in a linear shape between the first inductor pattern111aand the second inductor pattern111b. In the example ofFIG. 5, although the first inductor pattern111a, the second inductor pattern111b, and the connection pattern111ccorresponding to the inductor patterns are named separately for convenience of description, in another example the first inductor pattern111a, the second inductor pattern111b, and the connection pattern111cmay be formed to be continuous, so as to have the same material and shape.

The first inductor pattern111aand the second inductor pattern111bare configured to have rotational and symmetrical correspondence. In an example, the first inductor pattern111aand the second inductor pattern111bare provided symmetrically with respect to each other. When one of the first inductor pattern111aand the second inductor pattern111bis rotated 90 degrees, it has the same arrangement as an arrangement of the other one.

Specifically, in the example ofFIG. 5, when the first inductor pattern111ais rotated 90 degrees clockwise and then moved in an appropriate direction with respect to the X axis direction, the first inductor pattern111aand the second inductor pattern111boverlap with each other. Conversely, when the second inductor pattern111bis rotated 90 degrees counterclockwise and then moved in a direction opposite to the X axis direction, the second inductor pattern111band the first inductor pattern111aoverlap with each other.

The capacitor pattern111dis formed by being insulated from the first inductor pattern111a, the second inductor pattern111b, and the connection pattern111c. For example, the capacitor pattern111dis formed in an edge region of the first dielectric sheet111. Accordingly, the first inductor pattern111a, the second inductor pattern111b, and the connection pattern111care formed in a central region of the first dielectric sheet111. Thus, in the example ofFIG. 5, the capacitor pattern111dis insulated from the first inductor pattern111a, the second inductor pattern111b, and the connection pattern111c. In such an example, the capacitor pattern111dmay be provided with a ground potential from the ground portion120as shown inFIG. 3through a via different from the via connected to the first inductor pattern111aand the second inductor pattern111b.

The capacitor pattern111dis connected to the ground portion120to maintain the ground potential. A transmitting signal and a receiving signal are transmitted and received through any one or any combination of two or more of the first port P1, the second port P2and the third port P3. Such signals are provided to the inductor pattern. In this example, the inductor pattern includes the first inductor pattern111a, the second inductor pattern111b, and the connection pattern111c, between the inductor pattern and the capacitor pattern111dthat maintains the ground potential. In particular, the ground potential is maintained between an outermost loop of each of the first inductor pattern111aand the second inductor pattern111band the capacitor pattern111d. In such an example, a mutual capacitance component is generated between the elements and the mutual capacitance component potentially acts as the first capacitor C1and the second capacitor C2of the example ofFIG. 2.

According to an example, the first inductor pattern111aand the second inductor pattern111bare provided symmetrically so that the capacitances of the first and second capacitors C1and C2may be formed to be the same.

A direction of a signal path of a pattern disposed in parallel, located adjacent to the connection pattern111cin the outermost loop of each of the first inductor pattern111aand the second inductor pattern111bmay be the same as a direction of a signal path of the connection pattern111c. For example, assuming that a signal path is formed in the order of the first terminal T1, the second terminal T2, the fourth terminal T4, and the third terminal T3, a direction of a signal path of a pattern111a_I disposed in parallel, located adjacent to the connection pattern111cin the outermost loop of the first inductor pattern111ais formed in a Y axis direction, and the direction of a signal path of the connection pattern111cis formed in the Y axis direction. Also, a direction of a signal path of a pattern111b_I disposed in parallel, located adjacent to the connection pattern111cin the outermost loop of the second inductor pattern111bis formed in the Y axis direction, and the direction of a signal path of the connection pattern111cis formed in the Y axis direction.

According to an example, the directions of the signal paths of the patterns111a_I and111b_I arranged in parallel, adjacent to the connection pattern111cin the outermost loop of each of the first inductor pattern111aand the second inductor pattern111bare formed to be the same as the direction of the signal path of the connection pattern111c. Thus, the interference between inductance components generated by the first inductor pattern111a, the second inductor pattern111b, and the connection pattern111care potentially excluded.

Referring to the examples ofFIGS. 3 and 4again, the second dielectric sheet112includes one or more wiring patterns112a,112b.

The wiring patterns112aand112bconnect the first port P1, the second port P2and the third port P3provided in the ground portion120and the first inductor pattern111aand the second inductor pattern111b.

The wiring patterns112aand112binclude a first wiring pattern112aand a second wiring pattern112b. The first wiring pattern112ais connected to the first port P1formed on the first ground portion121, the second port P2formed on the second ground portion122, and the first inductor pattern111aformed on the first dielectric sheet111. Such a connection occurs through vias used to connect the first port P1, the second port P2and the first inductor pattern111ato each other. Also, the second wiring pattern112bis connected to the third port P3formed in the second ground portion122and the second inductor pattern112bformed in the first dielectric sheet111through a via used to connect the third port P3and the second inductor pattern112bto each other.

In the example ofFIG. 4, the second dielectric sheet112additionally includes an auxiliary capacitor pattern112c. In such an example, the auxiliary capacitor pattern112c, like the capacitor pattern111d, is connected to the ground portion120to maintain a ground potential. The auxiliary capacitor pattern112cof the second dielectric sheet112is formed to have the same shape as the capacitor pattern111dof the first dielectric sheet111. Using such a same shape increases a level of mutual capacitance generated by the capacitor pattern111d.

The ground portion120is provided on upper and lower portions of the stack dielectric sheet110to provide a ground potential. The ground portion120includes the first ground portion121disposed in the lower portion of the stack dielectric sheet110and the second ground portion122disposed in the upper portion of the stack dielectric sheet110. For example, the first grounding portion121is disposed in a lower portion of the first dielectric sheet111and the second ground portion122is disposed in an upper portion of the second dielectric sheet112.

In the examples ofFIGS. 2-3, the first port P1, the second port P2and the third port P3are formed in the first ground portion121and the second ground portion122. The first port P1, the second port P2and the third port P3ofFIGS. 3 and 4respectively correspond to the first port P1, the second port P2, and the third port P3ofFIG. 1.

In such examples, the first port P1is formed in the first ground portion121and the second port P2and the third port P3are formed in the second ground portion122. Thus, the first port P1, the second port P2and the third port P3formed in the first ground portion121and the second ground portion122are designed to be isolated and insulated from the ground potential.

As set forth above, the matching module according to an example maintains the same capacitance of at least two capacitors provided in an equivalent circuit and changes a phase while also maintaining a matched frequency band.