A microwave power device and its design method

Abstract

This invention provides a microwave power device and its design method. The device includes an input matching circuit and a power chip. The output terminal of the input matching circuit is connected to the input terminal of the power chip. The output terminal of the power chip is connected to the output terminal of the microwave power device. The input matching circuit includes a main matching capacitor, a matching resistor, and a secondary matching capacitor connected in sequence. The input terminal of the main matching capacitor serves as the input terminal of the input matching circuit. The output terminal of the secondary matching capacitor serves as the output terminal of the input matching circuit. The capacitance value of the main matching capacitor is greater than that of the secondary matching capacitor. This invention, by connecting the main matching capacitor, matching resistor, and secondary matching capacitor in sequence, places the matching resistor between the main and secondary matching capacitors. This makes the matching resistor closer to the power chip and allows for a smaller resistance value, reducing power loss and improving the efficiency and gain coefficient of the power device.

Description

Technical Field

[0001] This invention relates to the field of microwave power technology, and in particular to a microwave power device and its design method. Background Technology

[0002] Microwave power devices consist of a power chip and a matching circuit. The matching circuit is used to cancel the imaginary part of the power chip's impedance and to perform impedance transformation, ultimately matching the device's input and output impedance to 50Ω. Matching circuits can take various forms, including series resistor type, parallel resistor type, parallel feedback type, series feedback type, and balanced type. The most common method for improving the stability of microwave power devices is the series resistor type.

[0003] A series resistor matching circuit connects a resistor or a resistor-capacitor series at the input of the power chip. As the output power requirements of power devices in modern systems increase, the input power also increases accordingly, demanding higher power handling capabilities from the resistor. Consequently, the resistance value of the matching resistor connected in series at the input becomes increasingly larger. A larger series resistance at the input results in higher power consumption and lower efficiency and gain coefficient of the microwave power device. Summary of the Invention

[0004] This invention provides a microwave power device and its design method to solve the problems of high resistance and high power consumption of the matching resistor in the input matching circuit of the microwave power device.

[0005] In a first aspect, embodiments of the present invention provide a microwave power device, comprising: an input matching circuit and a power chip. The input terminal of the input matching circuit is connected to the input terminal of the microwave power device. The output terminal of the input matching circuit is connected to the input terminal of the power chip. The output terminal of the power chip is connected to the output terminal of the microwave power device. The input matching circuit includes a main matching capacitor, a matching resistor, and a secondary matching capacitor connected in sequence. The input terminal of the main matching capacitor serves as the input terminal of the input matching circuit. The output terminal of the secondary matching capacitor serves as the output terminal of the input matching circuit. The capacitance value of the main matching capacitor is greater than the capacitance value of the secondary matching capacitor.

[0006] In one possible implementation, the input matching circuit is an integrated device. The integrated device includes a ceramic substrate layer, a first metal layer disposed beneath the ceramic substrate layer, and a resistive layer disposed in a central region above the ceramic substrate layer. A second metal layer and a third metal layer are disposed on both sides of the resistive layer. The two sides of the resistive layer are electrically connected to the second and third metal layers, respectively. The second metal layer serves as the input terminal of the input matching circuit, and the third metal layer serves as the output terminal of the input matching circuit. The first and second metal layers constitute a primary matching capacitor. The resistive layer constitutes a matching resistor. The first and third metal layers constitute a secondary matching capacitor. The area of ​​the second metal layer is larger than the area of ​​the third metal layer.

[0007] In one possible implementation, the resistive layer, the second metal layer, and the third metal layer are rectangular in shape along a cross section parallel to the ceramic substrate layer.

[0008] In one possible implementation, the width of the second metal layer satisfies the following formula:

[0009] W=C*d / (ε0*ε r *L)

[0010] Where W is the width of the second metal layer, C is the capacitance value of the main matching capacitor, d is the thickness of the ceramic substrate layer, and ε0 is... r L is the relative permittivity of the ceramic substrate layer, and L is the length of the second metal layer, which is the dimension perpendicular to the line connecting the primary matching capacitor and the secondary matching capacitor.

[0011] In one possible implementation, the width of the resistive layer satisfies the following formula:

[0012] W′=L*R / R □

[0013] Where W′ is the width of the resistive layer, L is the length of the second metal layer, and R is the resistance value of the matching resistor. □ It is a sheet resistor of the resistive layer.

[0014] In one possible implementation, the primary matching capacitor, matching resistor, and secondary matching capacitor are discrete components. The primary matching capacitor, matching resistor, and secondary matching capacitor are connected sequentially via bonding wires.

[0015] In one possible implementation, the microwave power device further includes an output matching circuit. The input terminal of the output matching circuit is connected to the output terminal of the power chip. The output terminal of the output matching circuit is connected to the output terminal of the microwave power chip.

[0016] In one possible implementation, there are multiple input matching circuits and power chips, and each input matching circuit and power chip is connected in a one-to-one correspondence. The microwave power device further includes an input power divider and an output combiner. The input terminal of the input power divider serves as the input terminal of the microwave power device, and each output terminal is connected to the input terminal of each input matching circuit. Each input terminal of the output combiner is connected to the output terminal of each power chip, and its output terminal is connected to the output terminal of the microwave power device.

[0017] Secondly, embodiments of the present invention provide a design method for a microwave power device, the method being applied to any of the microwave power devices described in the first aspect. The method includes:

[0018] Based on the large-signal model of the power chip, the input impedance of the power chip is determined using microwave simulation software.

[0019] A lumped parameter circuit for microwave power devices is constructed based on an input matching circuit and a power chip. The input matching circuit includes a primary matching capacitor, a matching resistor, and a secondary matching capacitor connected in sequence.

[0020] Based on the input impedance of the power chip, the capacitance values ​​of the primary matching capacitor and the secondary matching capacitor, as well as the resistance value of the matching resistor, are determined through lumped parameter circuit simulation.

[0021] In one possible implementation, the input matching circuit is an integrated device. The integrated device includes a ceramic substrate layer, a first metal layer disposed below the ceramic substrate layer, and a resistive layer disposed in a central region above the ceramic substrate layer. A second metal layer and a third metal layer are disposed on both sides of the resistive layer. The two sides of the resistive layer are electrically connected to the second and third metal layers, respectively. The second metal layer serves as the input terminal of the input matching circuit, and the third metal layer serves as the output terminal of the input matching circuit. The first and second metal layers constitute a primary matching capacitor. The resistive layer constitutes a matching resistor. The first and third metal layers constitute a secondary matching capacitor. The area of ​​the second metal layer is larger than the area of ​​the third metal layer. The resistive layer, the second metal layer, and the third metal layer have a rectangular shape along a cross-section parallel to the ceramic substrate layer. The method further includes:

[0022] The width of the second metal layer is calculated using the following formula:

[0023] W=C*d / (ε0*ε r *L)

[0024] Where W is the width of the second metal layer, C is the capacitance value of the main matching capacitor, d is the thickness of the ceramic substrate layer, and ε0 is... r L is the relative permittivity of the ceramic substrate layer, and L is the length of the second metal layer, which is the dimension perpendicular to the line connecting the primary matching capacitor and the secondary matching capacitor.

[0025] The width of the resistive layer is calculated using the following formula:

[0026] W′=L*R / R □

[0027] Where W′ is the width of the resistive layer, L is the length of the second metal layer, and R is the resistance value of the matching resistor. □ It is a sheet resistor of the resistive layer.

[0028] This invention provides a microwave power device and its design method. The device includes an input matching circuit and a power chip. The input terminal of the input matching circuit is connected to the input terminal of the microwave power device. The output terminal of the input matching circuit is connected to the input terminal of the power chip. The output terminal of the power chip is connected to the output terminal of the microwave power device. The input matching circuit includes a main matching capacitor, a matching resistor, and a secondary matching capacitor connected in sequence. The input terminal of the main matching capacitor serves as the input terminal of the input matching circuit. The output terminal of the secondary matching capacitor serves as the output terminal of the input matching circuit. The capacitance value of the main matching capacitor is greater than that of the secondary matching capacitor. By connecting the main matching capacitor, the matching resistor, and the secondary matching capacitor in sequence, and placing the matching resistor between the main and secondary matching capacitors, the matching resistor is closer to the power chip, and its resistance value is smaller, thus reducing power loss and improving the efficiency and gain coefficient of the power device. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of a pre-matched microwave power device.

[0031] Figure 2 yes Figure 1 Circuit topology diagram of pre-matched microwave power devices;

[0032] Figure 3 This is a schematic diagram of the structure of an internally matched microwave power device;

[0033] Figure 4 This is a schematic diagram of a series resistive pre-matched microwave power device.

[0034] Figure 5 yes Figure 4 Topology diagram of series resistor pre-matching circuit;

[0035] Figure 6 This is a schematic diagram of a series-resistive internally matched microwave power device.

[0036] Figure 7 This is a schematic diagram of the structure of the microwave power device provided in the embodiment of the present invention;

[0037] Figure 8 This is a circuit topology diagram of the input matching circuit provided in an embodiment of the present invention;

[0038] Figure 9 This is a schematic diagram of the planar structure of the input matching circuit provided in an embodiment of the present invention;

[0039] Figure 10 This is provided by the embodiments of the present invention. Figure 9 Schematic diagram of section AA;

[0040] Figure 11 This is a schematic diagram of another microwave power device provided in an embodiment of the present invention;

[0041] Figure 12 This is a schematic diagram of the structure of the third microwave power device provided in the embodiments of the present invention. Detailed Implementation

[0042] To enable those skilled in the art to better understand this solution, the technical solutions in the embodiments of this solution will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this solution, not all of them. Based on the embodiments of this solution, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this solution.

[0043] The term "comprising" and any other variations thereof in the specification, claims, and accompanying drawings of this invention mean "including but not limited to," and are intended to cover a non-exclusive inclusion, not limited to the examples listed herein. Furthermore, the terms "first" and "second," etc., are used to distinguish different objects, not to describe a specific order.

[0044] The implementation of the present invention will be described in detail below with reference to the accompanying drawings:

[0045] With the rapid development of radar and communication technologies, electronic systems are becoming increasingly powerful, and their internal electromagnetic environments are becoming more complex, leading to more severe electromagnetic interference between functional units. Correspondingly, microwave power devices, in addition to requiring high gain, high power, and high efficiency, also face higher demands on their stability and anti-interference capabilities. Especially for high-power, high-gain microwave power devices, operational stability is one of the main factors affecting their long-term reliability. Different matching circuit configurations have a significant impact on the stability of microwave power devices.

[0046] Matching circuits for microwave power devices are typically designed together with the power chip inside the package. The matching circuit cancels out the imaginary part of the power chip's impedance and performs impedance transformation, ultimately matching the device's input and output impedances to 50Ω. Currently, commonly used matching circuit types for improving the stability of microwave power devices include series resistor matching, parallel resistor matching, parallel feedback matching, series feedback matching, and balanced matching. Microwave power devices are often packaged in standardized packages. Due to the limited internal dimensions of the package, the matching circuit design should not be complex; therefore, parallel feedback and balanced matching circuits are not suitable. Parallel resistor matching circuits are also unsuitable due to the power handling capacity of resistors. Series feedback matching is extremely sensitive to bond wire inductance, making device adjustment and mass production inconvenient. Therefore, the most common method for improving the stability of microwave power devices is the series resistor matching.

[0047] A series resistor matching circuit connects a resistor or a resistor-capacitor series at the input of the power chip. In traditional microwave power device matching circuit design, pre-matching is often used for L-band and lower frequency bands, for example... Figure 1 This is a schematic diagram of the structure of a pre-matched microwave power device, such as... Figure 1 As shown, a ceramic capacitor is connected in series at the input terminal of the power chip inside the casing. Figure 2 yes Figure 1 The circuit topology diagram of pre-matched microwave power devices. Due to the low power and small standard package size of L-band devices, a combination of internal pre-matching circuitry and external matching circuitry is required to meet impedance matching requirements. S-band and higher frequency bands often employ internal matching, for example... Figure 3 This is a schematic diagram of the structure of an internally matched microwave power device, such as... Figure 3 As shown, ceramic capacitors are connected in series between the input and output terminals of the power chip inside the housing. S-band power is high, and the standard housing size is relatively large; the internal matching circuit inside the housing can meet the impedance matching requirements. Traditional matching circuit designs do not comprehensively consider the stability of the device; series resistors can further improve the stability of microwave power devices. Corresponding to pre-matching and internal matching methods, series resistor matching circuits include two types: Method 1, Figure 4 This is a schematic diagram of a series resistive pre-matched microwave power device, such as... Figure 4 As shown, an impedance matching is achieved by connecting a resistor or a series resistor-capacitor circuit in series at the input terminal of the power chip inside the microwave power device housing, in conjunction with the external bias outside the housing. Figure 5 yes Figure 4 Topology diagram of series resistor pre-matched circuit. Method 2. Figure 6 This is a schematic diagram of a series-resistive internally matched microwave power device, such as... Figure 6As shown, independent ceramic resistors and capacitors are connected in series inside the microwave power device's casing and at the power chip's input port, while an independent ceramic capacitor is connected in series at the power chip's output port to improve device stability. Both of these series resistor methods have their own shortcomings.

[0048] In Method 1, the resistor R is typically implemented using a thin-film fixed resistor, with a resistance value usually ranging from tens of ohms to hundreds of ohms. The power handling capability of this resistor is typically from tens of milliwatts to several watts. As the output power requirements of power devices in the overall system increase, the input power also increases accordingly, placing higher demands on the power handling capability of this resistor. The power handling capability of the resistor has become one of the bottlenecks in the widespread application of this method. Furthermore, excessive power consumption across the resistor R will reduce the power-added efficiency and gain of the power devices, increasing system power consumption.

[0049] In method two, the resistor R is typically fabricated on a ceramic substrate using thin-film technology. For example, an independent ceramic resistor R and an independent ceramic capacitor C are connected by bonding wires to form a pre-matching circuit inside the device housing, raising the input impedance of the power chip to approximately 10 ohms. A secondary impedance transformation then occurs through a matching circuit outside the housing. Generally, the resistance value of the ceramic resistor in this method is between 3Ω and 6Ω. The power consumed by the resistor is relatively large, requiring high power handling capability from the thin-film resistor, which can negatively impact the gain and power-added efficiency of the power device. Furthermore, this method adds a matching resistor inside the power device housing, necessitating a reduction in the size of other matching circuits and increasing the complexity of matching circuit design. During micro-assembly, this increases assembly time and difficulty, and the number of bonding wires increases production costs and hinders production efficiency.

[0050] In summary, as the output power requirements of power devices in current systems increase, the input power also increases accordingly. This necessitates higher power handling capabilities from the resistors, leading to larger values ​​for the matching resistors connected in series at the input. A larger series resistor at the input results in higher power consumption and lower efficiency and gain coefficients for the microwave power devices.

[0051] This invention provides a microwave power device and its design method to solve the problems of high resistance and high power consumption of the matching resistor in the input matching circuit of the microwave power device.

[0052] Figure 7 This is a schematic diagram of a microwave power device provided in an embodiment of the present invention. (Refer to...) Figure 7The device includes an input matching circuit 100 and a power chip 200. The input terminal of the input matching circuit 100 is connected to the input terminal of the microwave power device. The output terminal of the input matching circuit 100 is connected to the input terminal of the power chip 200. The output terminal of the power chip 200 is connected to the output terminal of the microwave power device. The input matching circuit 100 includes a main matching capacitor C, a matching resistor R, and a secondary matching capacitor C' connected in sequence. The input terminal of the main matching capacitor C serves as the input terminal of the input matching circuit 100. The output terminal of the secondary matching capacitor C' serves as the output terminal of the input matching circuit 100. The capacitance value of the main matching capacitor C is greater than the capacitance value of the secondary matching capacitor.

[0053] For example, power chip 200 is a power amplifier chip. A power amplifier chip can amplify the power of an input signal before outputting it.

[0054] The input matching circuit 100 cancels the imaginary part of the impedance of the power chip 200 and performs impedance transformation, ultimately matching the input impedance of the device to 50Ω. Because the output signal of the power chip 200 has high power, it is not suitable to use a resistor in the output matching circuit. Because the input signal of the power chip 200 has relatively low power, a resistor can be used in the input matching circuit 100.

[0055] The input matching circuit 100 and the power chip 200 are connected in series. The input matching circuit 100 matches the impedance of the received external signal and outputs it to the power chip 200. The power chip 200 amplifies the power of the impedance-matched external signal and outputs it.

[0056] The input matching circuit 100 includes a primary matching capacitor C, a matching resistor R, and a secondary matching capacitor C' connected in sequence. The input terminal of the primary matching capacitor C serves as the input terminal of the input matching circuit 100, and its output terminal is connected to the input terminal of the matching resistor R. The output terminal of the matching resistor R is connected to the input terminal of the secondary matching capacitor C'. The output terminal of the secondary matching capacitor C' serves as the output terminal of the input matching circuit 100. For example, a bonding wire is connected to the input and output terminals of the input matching circuit 100; the bonding wire can be equivalent to an inductor. Figure 8 This is a circuit topology diagram of the input matching circuit 100 provided in an embodiment of the present invention. For example... Figure 8 As shown, the bonding wire can be considered equivalent to an inductor, and together with the primary matching capacitor C, the matching resistor R, and the secondary matching capacitor C', they form the input matching circuit. For example, one terminal of the primary matching capacitor C serves as both the input and output terminal, while the other terminal is grounded. Similarly, one terminal of the secondary matching capacitor C' serves as both the input and output terminal, while the other terminal is grounded.

[0057] The embodiments provided by the present invention, by connecting a main matching capacitor, a matching resistor and a secondary matching capacitor in sequence, and placing the matching resistor between the main matching capacitor and the secondary matching capacitor, the matching resistor is closer to the power chip and has a smaller resistance value, thereby reducing the power loss of the matching resistor and improving the efficiency and gain coefficient of the power device.

[0058] The matching circuit of the microwave power chip 200 is typically housed within the chip's package. Due to limited internal space, and as the power of the chip 200 increases, the resistors in the input matching circuit 100 also become larger. This limited internal space restricts the design of the input matching circuit 100.

[0059] Figure 9 This is a schematic diagram of the planar structure of the input matching circuit provided in an embodiment of the present invention. Figure 10 This is provided by the embodiments of the present invention. Figure 9 Schematic diagram of section AA in the middle. (Refer to...) Figure 9 and 10 :

[0060] In an optional embodiment, the input matching circuit 100 is an integrated device. The integrated device includes a ceramic substrate layer 101, a first metal layer 102 disposed below the ceramic substrate layer 101, and a resistive layer 103 disposed in the middle region above the ceramic substrate layer 101. A second metal layer 104 and a third metal layer 105 are disposed on both sides of the resistive layer 103. The two sides of the resistive layer 103 are electrically connected to the second metal layer 104 and the third metal layer 105, respectively. The second metal layer 104 serves as the input terminal of the input matching circuit 100, and the third metal layer 105 serves as the output terminal of the input matching circuit 100. The first metal layer 102 and the second metal layer 104 constitute a primary matching capacitor C. The resistive layer 103 constitutes a matching resistor R. The first metal layer 102 and the third metal layer 105 constitute a secondary matching capacitor C'. The area of ​​the second metal layer 104 is larger than the area of ​​the third metal layer 105.

[0061] The input matching circuit 100 is an integrated device, meaning the main matching capacitor C, matching resistor R, and secondary matching capacitor C' are integrated into a single unit. Unlike separately fabricated capacitors and resistors, the main matching capacitor C, matching resistor R, and secondary matching capacitor C' can be fabricated simultaneously using semiconductor manufacturing processes. Compared to separate devices, integrated devices shorten the electrical connection distance between individual devices and have a smaller overall size.

[0062] The ceramic substrate layer 101 has one side as its upper surface and the other side as its lower surface. A first metal layer 102 is disposed on the lower surface of the ceramic substrate layer 101. A resistive layer 103 is disposed in the middle region of the upper surface of the ceramic substrate layer 101, that is, the resistive layer 103 covers a portion of the upper surface of the ceramic substrate layer 101 near the middle. A second metal layer 104 and a third metal layer 105 cover portions on both sides of the resistive layer 103 on the upper surface of the ceramic substrate layer 101. The second metal layer 104 and the third metal layer 105 are electrically separated from each other by the resistive layer 103. The second metal layer 104 is electrically connected to one side of the resistive layer 103, and the third metal layer 105 is electrically connected to the other side of the resistive layer 103. For example, the second metal layer 104 covers a portion of one side of the upper surface of the resistive layer 103, and the third metal layer 105 covers a portion of the other side of the upper surface of the resistive layer 103 to achieve electrical connection. For example, the second metal layer 104 is electrically connected to one side of the resistive layer 103 via a bonding wire, and the third metal layer 105 is electrically connected to the other side of the resistive layer 103 via a bonding wire.

[0063] The first metal layer 102 and the second metal layer 104 constitute the main matching capacitor C. The first metal layer 102 and the second metal layer 104 are isolated by the ceramic substrate layer 101. The first metal layer 102 and the second metal layer 104 serve as the two terminals of the main matching capacitor C. The ceramic substrate layer 101 serves as the dielectric material of the main matching capacitor C.

[0064] The resistive layer 103 forms a matching resistor R. The two sides of the resistive layer 103 are electrically connected to the second metal layer 104 and the third metal layer 105.

[0065] The first metal layer 102 and the third metal layer 105 constitute a secondary matching capacitor C'. The first metal layer 102 and the third metal layer 105 are isolated by a ceramic substrate layer 101. The first metal layer 102 and the third metal layer 105 serve as the two terminals of the secondary matching capacitor C'. The ceramic substrate layer 101 serves as the dielectric material of the secondary matching capacitor C'. Exemplarily, the first metal layer 102 is grounded.

[0066] The area of ​​the second metal layer 104 is larger than the area of ​​the third metal layer 105. The ceramic substrate layer 101 serves as the capacitor dielectric material and has a uniform thickness. The areas of the second metal layer 104 and the third metal layer 105 determine the capacitance values ​​of the primary matching capacitor C and the secondary matching capacitor C', respectively. The fact that the area of ​​the second metal layer 104 is larger than the area of ​​the third metal layer 105 allows the capacitance value of the primary matching capacitor C to be greater than that of the secondary matching capacitor C'.

[0067] The ceramic substrate layer 101 is made of alumina ceramic or zirconium titanate ceramic. Exemplarily, the first metal layer 102, the second metal layer 104, and the third metal layer 105 are made of the same material. The material of each metal layer may be gold. The resistive layer 103 is made of chromium nickelate or tantalum nitride.

[0068] The input matching circuit 100 provided in this embodiment of the invention is designed as an integrated device, which improves the device integration level, avoids the use of bonding wires to connect independent devices, reduces the distance between devices, and reduces the overall size of the input matching circuit. More complex input matching circuits with higher power tolerance can be implemented within a space-constrained housing.

[0069] In an optional embodiment, the resistive layer 103, the second metal layer 104, and the third metal layer 105 are rectangular in shape along a cross-section parallel to the ceramic substrate layer 101. Figure 7 As shown, from a planar normal view of the upper surface of the ceramic substrate layer 101, the resistive layer 103, the second metal layer 104, and the third metal layer 105 are rectangular. Exemplarily, the second metal layer 104, the resistive layer 103, and the third metal layer 105 are sequentially connected rectangles, meaning the second metal layer 104 is directly electrically connected to the resistive layer 103, and the resistive layer 103 is directly electrically connected to the third metal layer 105. Exemplarily, the second metal layer 104 covers a portion of one side of the upper surface of the resistive layer 103, and the third metal layer 105 covers a portion of the other side of the upper surface of the resistive layer 103 to achieve electrical connection.

[0070] The thickness and dimensions of each layer in an integrated device determine the capacitance values ​​of the primary matching capacitor C and the secondary matching capacitor C', as well as the resistance value of the matching resistor R. Thin films fabricated using semiconductor manufacturing processes typically have uniform thickness. After determining the capacitance and resistance values ​​through simulation, the dimensions of each layer can be determined based on these values.

[0071] In an optional embodiment, the width of the second metal layer 104 satisfies the following formula:

[0072] W=C*d / (ε0*ε r *L)

[0073] Where W is the width of the second metal layer 104, and the width of the second metal layer 104 is the dimension parallel to the direction of the line connecting the main matching capacitor C and the secondary matching capacitor C'. C is the capacitance value of the main matching capacitor, d is the thickness of the ceramic substrate layer 101, ε0 is... r L is the relative permittivity of the ceramic substrate layer 101, and L is the length of the second metal layer 104, which is the dimension perpendicular to the line connecting the primary matching capacitor C and the secondary matching capacitor C'.

[0074] The area of ​​the third metal layer 105 is smaller than the area of ​​the second metal layer 104. For example, the length of the third metal layer 105 is the same as that of the second metal layer 104, and the width of the third metal layer 105 is smaller than that of the second metal layer 104. For example, the width of the third metal layer 105 must at least meet the bonding process requirements. For example, the width of the third metal layer 105 is greater than 200 micrometers.

[0075] For example, the resistive layer 103 and the second metal layer 104 have the same length, and the width of the resistive layer 103 can be determined by the resistance value and the length of the second metal layer 104.

[0076] In an optional embodiment, the width of the resistive layer 103 satisfies the following formula:

[0077] W′=L*R / R □

[0078] Where W′ is the width of the resistive layer 103, L is the length of the second metal layer 104, and R is the resistance value of the matching resistor R. □ This is a sheet resistor for resistive layer 103.

[0079] In an optional embodiment, the primary matching capacitor C, the matching resistor R, and the secondary matching capacitor C' are discrete components. The primary matching capacitor C, the matching resistor R, and the secondary matching capacitor C' are connected sequentially by bonding wires.

[0080] Discrete components are a concept relative to integrated circuits. Discrete components are the smallest units in a circuit, such as electronic components like capacitors, resistors, and inductors. Discrete components can be electrically connected to each other using bonding wires.

[0081] The main matching capacitor C, matching resistor R, and secondary matching capacitor C' of the input matching circuit 100 are discrete components. The main matching capacitor C is connected to the matching resistor R via bonding wires, and the matching resistor R is connected to the secondary matching capacitor C' via bonding wires. For example, multiple bonding wires connect the two discrete components. The main matching capacitor C is connected to the matching resistor R via multiple bonding wires, and the matching resistor R is connected to the secondary matching capacitor C' via multiple bonding wires. Using multiple bonding wires to electrically connect the two independent components increases the reliability of the connection.

[0082] Figure 11 This is a schematic diagram of another microwave power device provided in an embodiment of the present invention. (Refer to...) Figure 11 In an optional embodiment, the microwave power device further includes an output matching circuit 300. The input terminal of the output matching circuit 300 is connected to the output terminal of the power chip 200. The output terminal of the output matching circuit 300 is connected to the output terminal of the microwave power chip 200. Exemplarily, the output matching circuit 300 is a capacitor. Exemplarily, the output matching circuit 300 is a ceramic capacitor.

[0083] In microwave power devices, the power of a single power chip 200 cannot meet the requirements for high power. High-power microwave power devices can be realized by accumulating the power of multiple power chips 200. Figure 12 This is a schematic diagram of the structure of the third microwave power device provided in an embodiment of the present invention. (Refer to...) Figure 12 :

[0084] In an optional embodiment, there are multiple input matching circuits 100 and power chips 200, and each input matching circuit 100 and power chip 200 is connected in a one-to-one correspondence. The microwave power device also includes an input power divider 400 and an output combiner 500. The input terminal of the input power divider 400 serves as the input terminal of the microwave power device, and each output terminal is connected to the input terminal of each input matching circuit 100 in a one-to-one correspondence. Each input terminal of the output combiner 500 is connected to the output terminal of each power chip 200 in a one-to-one correspondence, and the output terminal is connected to the output terminal of the microwave power device.

[0085] The input power divider 400 receives external signals and splits them into multiple signals of equal power. Each signal undergoes impedance transformation by the corresponding input matching circuit 100 and is amplified by the power chip 200 before being combined into a single output by the output combiner 500. For example, the input power divider 400 and the output combiner 500 are in the form of planar microstrip circuits.

[0086] This invention provides a design method for a microwave power device, applicable to the design of any of the microwave power devices described in this invention. The method includes:

[0087] Based on the large-signal model of power chip 200, the input impedance of power chip 200 is determined using microwave simulation software.

[0088] A lumped parameter circuit for a microwave power device is constructed based on an input matching circuit 100 and a power chip 200. The input matching circuit 100 includes a primary matching capacitor C, a matching resistor R, and a secondary matching capacitor C' connected in sequence.

[0089] Based on the input impedance of the power chip 200, the capacitance values ​​of the primary matching capacitor C and the secondary matching capacitor C', as well as the resistance value of the matching resistor R, are determined through lumped parameter circuit simulation.

[0090] For example, the bonding wires at the input and output ends of the input matching circuit 100 are used as inductors. Based on the input impedance of the power chip 200, the capacitance values ​​of the primary matching capacitor C and the secondary matching capacitor C', as well as the resistance value of the matching resistor R, are determined through simulation.

[0091] The embodiments provided by this invention connect a main matching capacitor, a matching resistor, and a secondary matching capacitor in sequence. The matching resistor is positioned between the main matching capacitor and the secondary matching capacitor. The capacitance value of the secondary matching capacitor is smaller than that of the main matching capacitor. The matching resistor is closer to the power chip and has a smaller resistance value (generally less than 1Ω), which is 1 / 6 to 1 / 4 of the resistance value in traditional discrete capacitor and resistor ceramic matching circuits. This not only improves the stability factor of the device and enhances its stability, but also significantly reduces the power loss of the matching resistor, thereby improving the efficiency and gain coefficient of the power device.

[0092] In an optional embodiment, the input matching circuit 100 is an integrated device. The integrated device includes a ceramic substrate layer 101, a first metal layer 102 disposed below the ceramic substrate layer 101, and a resistive layer 103 disposed in the middle region above the ceramic substrate layer 101. A second metal layer 104 and a third metal layer 105 are disposed on both sides of the resistive layer 103. The two sides of the resistive layer 103 are electrically connected to the second metal layer 104 and the third metal layer 105, respectively. The second metal layer 104 serves as the input terminal of the input matching circuit 100, and the third metal layer 105 serves as the output terminal of the input matching circuit 100. The first metal layer 102 and the second metal layer 104 constitute a primary matching capacitor C. The resistive layer 103 constitutes a matching resistor R. The first metal layer 102 and the third metal layer 105 constitute a secondary matching capacitor C'. The area of ​​the second metal layer 104 is larger than the area of ​​the third metal layer 105. The resistive layer 103, the second metal layer 104, and the third metal layer 105 are rectangular in shape along a cross-section parallel to the ceramic substrate layer 101. The above methods also include:

[0093] The width of the second metal layer 104 is calculated using the following formula:

[0094] W=C*d / (ε0*ε r *L)

[0095] Where W is the width of the second metal layer 104, C is the capacitance value of the main matching capacitor, d is the thickness of the ceramic substrate layer 101, and ε0 is... r L is the relative permittivity of the ceramic substrate layer 101, and L is the length of the second metal layer 104, which is the dimension perpendicular to the line connecting the primary matching capacitor C and the secondary matching capacitor C'.

[0096] The width of resistive layer 103 is calculated using the following formula:

[0097] W′=L*R / R □

[0098] Where W′ is the width of the resistive layer 103, L is the length of the second metal layer 104, and R is the resistance value of the matching resistor R. □ This is a sheet resistor for resistive layer 103.

[0099] For example, the lengths of the second metal layer 104, the resistive layer 103, and the third metal layer 105 can be set to be consistent with the gate length of the power chip 200. The third metal layer 105 is connected to the gate of the power chip 200 via a bonding wire, and the width of the third metal layer 105 must at least meet the bonding process requirements. The resistive layer cannot be directly electrically connected to the power chip; the electrical connection is achieved through the third metal layer. For example, the width of the third metal layer 105 is greater than 200 micrometers.

[0100] By iteratively correcting the physical dimensions of the primary matching capacitor C, the matching resistor R, and the secondary matching capacitor C' using electromagnetic simulation, the imaginary part of the power chip 200's input impedance is canceled out, increasing the real part of the power chip 200's input impedance from a few tenths of an ohm to several ohms or even tens of ohms. For example, the real part of the power chip 200's input impedance can be transformed to 50Ω.

[0101] The design method provided in this invention features a compact input matching circuit layout without increasing circuit size. It has a high application frequency, reduces the number of assembly components, shortens sintering time, and reduces the number of bonding wires, thus improving product consistency, increasing production efficiency, and reducing production costs. It can be widely applied to the design of matching circuits for high-power devices, facilitating device miniaturization. The microwave power devices implemented using the design method provided in this invention can be directly used in standard 50Ω electronic systems, meeting the requirements of communication, radar, and other electronic systems for high power, high efficiency, miniaturization, and high reliability of solid-state power amplifiers and other components.

[0102] For a microwave power device with a combined structure of multiple power chips 200, each power chip 200 corresponds to one input matching circuit 100. An input power divider 400, in the form of a planar microstrip circuit, distributes the input power to each input matching circuit 100. Each input matching circuit 100 transforms the impedance of the input terminal of the power chip 200 to 50Ω. Using CAD software, the input matching circuit 100, power chips 200, input power divider 400, and output combiner 500 within the microwave power device are simulated as a whole. This further optimizes the physical dimensions of the resistors and capacitors in the input matching circuit 100, improves the device stability factor, and yields the power device circuit topology and design values ​​that meet the device performance requirements.

[0103] When assembling the above-mentioned input matching circuit 100, gold-tin solder can be used to sinter the input matching circuit 100 into the microwave power device package shell or carrier. Bonding wires are used to connect the main matching capacitor C and the secondary matching capacitor C' of the input matching circuit 100 to the device input terminal and the corresponding power chip 200 input terminal electrodes, respectively.

[0104] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A microwave power device, characterized in that, include: Input matching circuit and power chip; The input terminal of the input matching circuit is connected to the input terminal of the microwave power device; the output terminal of the input matching circuit is connected to the input terminal of the power chip; and the output terminal of the power chip is connected to the output terminal of the microwave power device. The input matching circuit includes a main matching capacitor, a matching resistor, and a secondary matching capacitor connected in sequence; the input terminal of the main matching capacitor serves as the input terminal of the input matching circuit; and the output terminal of the secondary matching capacitor serves as the output terminal of the input matching circuit. The capacitance value of the primary matching capacitor is greater than that of the secondary matching capacitor. The input matching circuit is an integrated device; The integrated device includes a ceramic substrate layer, a first metal layer disposed below the ceramic substrate layer, and a resistive layer disposed in the middle region above the ceramic substrate layer. A second metal layer and a third metal layer are provided on both sides of the resistive layer; The two sides of the resistive layer are electrically connected to the second metal layer and the third metal layer, respectively. The second metal layer serves as the input terminal of the input matching circuit, and the third metal layer serves as the output terminal of the input matching circuit. In this configuration, the first metal layer and the second metal layer constitute the main matching capacitor; the resistor layer constitutes the matching resistor; the first metal layer and the third metal layer constitute the secondary matching capacitor; and the area of ​​the second metal layer is larger than the area of ​​the third metal layer.

2. The microwave power device as described in claim 1, characterized in that, The resistive layer, the second metal layer, and the third metal layer are rectangular in shape along a cross section parallel to the ceramic substrate layer.

3. The microwave power device as described in claim 2, characterized in that, The width of the second metal layer satisfies the following formula: W=C d / (ε0 ε r L) Where W is the width of the second metal layer, C is the capacitance value of the main matching capacitor, d is the thickness of the ceramic substrate layer, and ε r L is the relative permittivity of the ceramic substrate layer, and L is the length of the second metal layer, which is the dimension perpendicular to the line connecting the primary matching capacitor and the secondary matching capacitor.

4. The microwave power device as described in claim 3, characterized in that, The width of the resistive layer satisfies the following formula: W´=L R / R □ Where W' is the width of the resistive layer, L is the length of the second metal layer, and R is the resistance value of the matching resistor. □ It is a sheet resistor of the resistive layer.

5. The microwave power device as described in claim 1, characterized in that, The microwave power device also includes an output matching circuit; The input terminal of the output matching circuit is connected to the output terminal of the power chip; The output terminal of the output matching circuit is connected to the output terminal of the microwave power device.

6. The microwave power device as described in claim 1, characterized in that, There are multiple input matching circuits and multiple power chips, and each input matching circuit and power chip is connected in a one-to-one correspondence. The microwave power device also includes an input power divider and an output combiner; The input terminal of the input power divider serves as the input terminal of the microwave power device, and each output terminal is connected to the input terminal of each input matching circuit in a one-to-one correspondence. Each input terminal of the output synthesizer is connected to the output terminal of each power chip in a one-to-one correspondence, and the output terminal is connected to the output terminal of the microwave power device.

7. A design method for a microwave power device, characterized in that, The method, applied to the design of a microwave power device as described in any one of claims 1 to 6, comprises: Based on the large-signal model of the power chip, the input impedance of the power chip is determined using microwave simulation software; A lumped parameter circuit for microwave power devices is constructed based on an input matching circuit and a power chip; the input matching circuit includes a main matching capacitor, a matching resistor, and a secondary matching capacitor connected in sequence. Based on the input impedance of the power chip, the capacitance values ​​of the primary matching capacitor and the secondary matching capacitor, as well as the resistance value of the matching resistor, are determined through lumped parameter circuit simulation.

8. The design method for microwave power devices as described in claim 7, characterized in that, The input matching circuit is an integrated device; the integrated device includes a ceramic substrate layer, a first metal layer disposed below the ceramic substrate layer, and a resistor layer disposed in the middle region above the ceramic substrate layer; a second metal layer and a third metal layer are disposed on both sides of the resistor layer; the two sides of the resistor layer are electrically connected to the second metal layer and the third metal layer respectively; the second metal layer serves as the input terminal of the input matching circuit, and the third metal layer serves as the output terminal of the input matching circuit; wherein, the first metal layer and the second metal layer constitute a main matching capacitor; the resistor layer constitutes a matching resistor; the first metal layer and the third metal layer constitute a secondary matching capacitor; the area of ​​the second metal layer is larger than the area of ​​the third metal layer; the shape of the resistor layer, the second metal layer, and the third metal layer along a cross section parallel to the ceramic substrate layer is rectangular; the method further includes: The width of the second metal layer is calculated using the following formula: W=C d / (ε0 ε r L) Where W is the width of the second metal layer, C is the capacitance value of the main matching capacitor, d is the thickness of the ceramic substrate layer, and ε r is the relative permittivity of the ceramic substrate layer, and L is the length of the second metal layer, which is the dimension perpendicular to the line connecting the main matching capacitor and the secondary matching capacitor. The width of the resistive layer is calculated using the following formula: W´=L R / R □ Where W' is the width of the resistive layer, L is the length of the second metal layer, and R is the resistance value of the matching resistor. □ It is a sheet resistor of the resistive layer.

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