CN114647212A

CN114647212A - Radio frequency module and corresponding equipment control circuit

Info

Publication number: CN114647212A
Application number: CN202210327501.5A
Authority: CN
Inventors: 蔡明星; 李艳飞
Original assignee: Shenzhen One Nine Intelligent Electronic Technology Co ltd
Current assignee: Shenzhen One Nine Intelligent Electronic Technology Co ltd
Priority date: 2021-03-31
Filing date: 2021-03-31
Publication date: 2022-06-21
Also published as: CN113093606B; CN113093606A

Abstract

The invention provides a radio frequency module which is used for receiving radio signals and sending wired electric signals. The radio frequency module comprises a radio frequency circuit, and the radio frequency circuit is provided with a radio frequency signal wire, a radio frequency control chip and an antenna. The radio frequency signal line is used for bidirectional transmission of radio frequency signals between the antenna and the control chip and has characteristic impedance. Based on different circuit structures, the structure of the radio frequency signal line is a micro-strip line structure, a coplanar waveguide structure or a micro-strip line combined coplanar waveguide structure. The radio frequency module is applied to a device control circuit.

Description

Radio frequency module and corresponding equipment control circuit

The present application is a divisional application of a patent application having a patent application number "202110351016.7" filed on "03/31/2021 and entitled" device control circuit ".

Technical Field

The present invention relates to the field of integrated circuits, and in particular, to an apparatus control circuit.

Background

In the field of integrated circuits today, the characteristic impedance of a transmission line is the most important factor affecting signal quality. In the process of signal propagation, there is a difference in propagation intervals between adjacent signals, or the characteristic impedance of the transmission line is easily changed. Since the characteristic impedance of the transmission line is subject to change, a portion of the energy in the signal is reflected back. The integrity of the signal transmission is affected and the signal quality transmitted by the signal line is poor. Therefore, the existing transmission line has the technical problem that the characteristic impedance is easy to change.

Therefore, it is desirable to provide a radio frequency module and a corresponding device control circuit to solve the above technical problems.

Disclosure of Invention

The invention provides a radio frequency module and a corresponding equipment control circuit. The device control circuit can be based on different circuit structures, and the radio frequency signal line structure of the device control circuit can be a microstrip line structure, a coplanar waveguide structure or a microstrip line combined coplanar waveguide structure. The technical problem that the characteristic impedance of the existing transmission line is easy to change is effectively solved.

The present invention provides a radio frequency module, comprising:

the radio frequency module is used for receiving radio signals and sending wired electric signals; the radio frequency module comprises a radio frequency circuit, the radio frequency circuit is provided with a radio frequency signal line, a radio frequency control chip and an antenna, the radio frequency signal line is used for bidirectional transmission of radio frequency signals between the antenna and the control chip, the radio frequency signal line has characteristic impedance, and the radio frequency signal line is in a microstrip line structure, a coplanar waveguide structure or a microstrip line combined coplanar waveguide structure based on different circuit structures;

when two groups of radio frequency signal wires transmit signals, the microstrip line combined coplanar waveguide structure is a three-layer PCB structure which comprises a coplanar waveguide and a microstrip line, the coplanar waveguide comprises a third radio frequency signal wire and a second ground wire, the third radio frequency signal wire is arranged in the middle of the first layer of the microstrip line combined coplanar waveguide structure, the second ground wire is arranged at two ends of the third radio frequency signal wire, and the distance between the second ground wire and the third radio frequency signal wire is a ground clearance;

the microstrip line is arranged on the second layer and the third layer, the microstrip line comprises a fourth radio frequency signal line, a second ground hole, a second ground layer and a power layer, the fourth radio frequency signal line is arranged on the second layer of the microstrip line combined coplanar waveguide structure, the second ground layer is arranged on the third layer of the microstrip line combined coplanar waveguide structure, the second ground hole is arranged between the fourth radio frequency signal line and the second ground layer, the horizontal distance between the second ground hole and the fourth radio frequency signal line is at least twice the line width of the third radio frequency signal line, and the distance between the third radio frequency signal line and the second ground layer is the height of the reference ground plane;

when two groups of radio frequency signal wires transmit signals and shield the interference of a power supply, the microstrip line combined coplanar waveguide structure is a four-layer PCB structure which comprises a coplanar waveguide and a microstrip line, the coplanar waveguide comprises a fifth radio frequency signal wire and a third ground wire, the fifth radio frequency signal wire is arranged in the middle of the first layer of the microstrip line combined coplanar waveguide structure, the third ground wire is arranged at two ends of the fifth radio frequency signal wire, and the distance between the third ground wire and the fifth radio frequency signal wire is a ground gap;

the microstrip line is arranged on the second layer, the third layer and the fourth layer, the microstrip line comprises a sixth radio frequency signal line, a third ground hole, a third ground layer and a power layer, the sixth radio frequency signal line is arranged on the second layer of the microstrip line combined coplanar waveguide structure, the third ground layer is arranged on the third layer or the fourth layer of the microstrip line combined coplanar waveguide structure, the power layer is arranged on the third layer or the fourth layer of the microstrip line combined coplanar waveguide structure, the second ground hole is arranged between the sixth radio frequency signal line and the third ground layer, the horizontal distance between the third ground hole and the sixth radio frequency signal line is at least twice the line width of the fifth radio frequency signal line, and the distance between the fifth radio frequency signal line and the third ground layer is the height of the reference ground plane;

coplanar waveguide includes the recess, the recess set up in fifth radio frequency signal line with the lower extreme of third ground wire and being located between first layer and the second floor, the recess includes first side and second side, the length of first side is greater than the length of second side, the bottom of recess is notch cuttype or arc type, the circular arc of arc type is inferior arc, inferior arc protrusion or cave in the recess.

In the radio frequency module of the present invention, the microstrip line structure is a two-layer PCB microstrip line structure, the two-layer PCB microstrip line structure includes a first ground hole, a first radio frequency signal line, and a first ground layer, the first ground layer is disposed on a second layer of the two-layer PCB microstrip line structure, the first radio frequency signal line is disposed in a middle portion of a first layer of the two-layer PCB microstrip line structure, the first ground hole is disposed between the first radio frequency signal line and the first ground layer, a horizontal distance between the first ground hole and the first radio frequency signal line is at least twice a line width of the first radio frequency signal line, and a distance between the first radio frequency signal line and the first ground layer is a height of a reference ground plane.

In the radio frequency module of the present invention, the coplanar waveguide structure includes two layers of PCB coplanar waveguide structures, each of the two layers of PCB coplanar waveguide structures includes a first ground line, a second radio frequency signal line, and a reference ground, the second radio frequency signal line is disposed in the middle of a first layer of the two layers of PCB coplanar waveguide structures, the reference ground is disposed in a second layer of the two layers of PCB coplanar waveguide structures, the first ground line is disposed at two ends of the second radio frequency signal line, a distance between the first ground line and the second radio frequency signal line is a ground gap, and a distance between the first ground line and the reference ground is a height of the reference ground plane.

An apparatus control circuit, comprising:

the radio frequency module of any of the above;

the control chip is connected with the radio frequency module and used for receiving data, processing the data and sending the data;

and the power supply module is connected with the control chip and the radio frequency module and is used for providing working voltage for the control chip and the radio frequency module.

In the device control circuit of the present invention, the device control circuit with the rf module further includes a camera module, the camera module is connected to the control chip, the camera module is configured to transmit video data and image data to the control chip, the camera module is further connected to the power supply module, and the power supply module is configured to provide a working voltage of the camera module.

In the device control circuit of the present invention, the camera module includes a camera interface circuit, the camera interface circuit includes a clock connection line and a data connection line, a camera interface, and a camera control chip, the clock connection line is used for the camera interface to transmit a clock signal to the camera control chip, and the data connection line is used for the camera interface to transmit a data signal to the camera control chip; the clock connecting line and the data connecting line are high-speed signal lines with set characteristic impedance and are differential signal lines, the line length of the clock connecting line and the data connecting line is a first set value, at least two data connecting lines form the data connecting line of the same video assembly, the length difference of the data connecting line of the same video assembly is a second set value, and the length difference of the data connecting lines between different video assemblies is a third set value.

In the device control circuit of the present invention, the camera interface circuit includes an analog part power supply and a digital part power supply, and the analog part power supply and the digital part power supply are respectively supplied with power by different low dropout linear regulators.

In the device control circuit provided by the invention, the device control circuit with the radio frequency module further comprises an audio module, the audio module is connected with the control chip and is used for transmitting audio data to the control chip and receiving the audio data of the control chip, the audio module is further connected with the power supply module, and the power supply module is used for connecting the working voltage of the audio module.

In the device control circuit of the present invention, the audio module includes an electret microphone circuit and an earphone circuit, the electret microphone circuit is connected in parallel with the earphone circuit, the electret microphone circuit includes a microphone input end, a first filter capacitor and a second filter capacitor, the first filter capacitor and the second filter capacitor are used for filtering out radio frequency interference, the first filter capacitor is connected in parallel with the electret microphone circuit, the second filter capacitor is connected in parallel with the electret microphone circuit, a distance between the first filter capacitor and the microphone input end is smaller than a distance between the first filter capacitor and the control chip, and a distance between the second filter capacitor and the microphone input end is smaller than a distance between the second filter capacitor and the control chip; the earphone circuit comprises an earphone interface and a third filter capacitor, the third filter capacitor is used for filtering radio frequency interference, the third filter capacitor is connected with the earphone circuit in parallel, and the distance between the third filter capacitor and the earphone interface is smaller than that between the third filter capacitor and the control chip.

In the device control circuit, the earphone circuit is connected with a magnetic bead in series, and the distance between the magnetic bead and the earphone interface is smaller than the distance between the magnetic bead and the control chip.

Compared with the prior art, the invention has the beneficial effects that: the invention provides a device control circuit, wherein a radio frequency signal wire of the device control circuit has characteristic impedance. The device control circuit can be based on different circuit structures, and the radio frequency signal line structure of the device control circuit can be a microstrip line structure, a coplanar waveguide structure or a microstrip line combined coplanar waveguide structure, so that the technical problem that the characteristic impedance of the existing transmission line is easy to change is effectively solved.

The microstrip line combined coplanar waveguide structure comprises a groove, the groove is arranged at the lower ends of the fifth radio-frequency signal line and the third ground wire, and the groove is positioned between the first layer and the second layer of the microstrip line combined coplanar waveguide structure. The bottom of the groove is in a step shape or an arc shape, so that the transmission loss can be reduced, and meanwhile, the strength of the microstrip line combined with the coplanar waveguide structure can be ensured to be higher by the groove with the step shape or the arc shape at the bottom.

The camera interface circuit is provided with a clock connecting wire and a data connecting wire, wherein the clock connecting wire and the data connecting wire are high-speed signal wires with characteristic impedance and are differential signal wires. The line length of the clock connecting line and the data connecting line is a first set value, and the first set value is 100mm-305 mm. The at least two data connecting lines form the data connecting lines of the same video assembly, the length difference of the data connecting lines of the same video assembly is a second set value, and the second set value is 0-1.5 mm. The difference in the length of the data link between the different video modules is a third setting of 0.3.3 mm. The noise interference signals are equivalently and simultaneously loaded on the differential signal lines, so that the noise interference signal difference is zero, and the noise interference signals do not influence the logic significance of the data signals. Differential signal lines may be used to reduce the effects of noise interference signals.

The audio module comprises an electret microphone circuit and an earphone circuit, wherein the electret microphone circuit is provided with a first filter capacitor and a second filter capacitor. The distance between the first filter capacitor and the microphone input end is smaller than the distance between the first filter capacitor and the control chip, and the distance between the second filter capacitor and the microphone input end is smaller than the distance between the second filter capacitor and the control chip. The earphone circuit is provided with a third filter capacitor, and the distance between the third filter capacitor and the earphone interface is smaller than the distance between the third filter capacitor and the control chip. The first filter capacitor, the second filter capacitor and the third filter capacitor can better filter radio frequency interference. The earphone circuit is connected with the magnetic bead in series, and the distance of magnetic bead and earphone interface is less than the distance of magnetic bead and control chip, and the magnetic bead suppresses noise interference on the earphone circuit better.

Drawings

FIG. 1 is a block diagram of one embodiment of a device control circuit of the present invention;

fig. 2 is a circuit diagram of a camera module of an embodiment of the device control circuitry of the present invention;

fig. 3 is a circuit diagram of an electret microphone circuit of a headphone module of an embodiment of the device control circuit of the present invention;

fig. 4 is a circuit diagram of an earphone circuit of an earphone module of an embodiment of the device control circuit of the present invention;

FIG. 5 is a circuit diagram of an RF module according to an embodiment of the device control circuit of the present invention;

FIG. 6 is a schematic diagram of a microstrip line structure of an embodiment of a device control circuit of the present invention;

FIG. 7 is a schematic diagram of a coplanar waveguide structure of one embodiment of the device control circuitry of the present invention;

fig. 8 is a schematic diagram of a microstrip line in combination with a coplanar waveguide structure of the device control circuit of the present invention in a first embodiment.

Fig. 9 is a schematic diagram of a microstrip line in combination with a coplanar waveguide structure of a device control circuit according to a second embodiment of the present invention;

figure 10 is a schematic diagram of a third embodiment of a microstrip line in combination with a coplanar waveguide structure of the device control circuit of the present invention;

fig. 11 is a second schematic diagram of a microstrip line combined with a coplanar waveguide structure of a second embodiment of the apparatus control circuit of the present invention;

fig. 12 is a third schematic diagram of a microstrip line in combination with a coplanar waveguide structure of an embodiment of a device control circuit of the present invention;

fig. 13 is a fourth schematic diagram of a microstrip line in combination with a second embodiment of a coplanar waveguide structure of an embodiment of the device control circuit of the present invention;

in the figure, 10, a device control circuit; 11. a control chip; 12. a camera module; 121. a camera interface; 122. a clock connecting line; 123. a data link; 13. an audio module; 131. an electret microphone circuit; 1311 a microphone input; 132. an earphone circuit; 1321. an earphone detection circuit; 1322. a microphone interface circuit; 1323. an earphone interface circuit; 14. a radio frequency module; 141. a radio frequency control chip; 142. a radio frequency signal line; 1421. a microstrip line structure; 14211. a first radio frequency signal line; 14212. a first ground plane; 14213. a first ground hole; 1422. a coplanar waveguide structure; 14221. a first ground line; 14222. a second radio frequency signal line; 14223. a reference ground; 1423. the microstrip line is combined with the coplanar waveguide structure; 14231. a third radio frequency signal line; 14232. a second ground line; 14233. a fourth radio frequency signal line; 14234. a second ground plane; 14235. a second ground hole; 1424. the microstrip line is combined with the coplanar waveguide structure; 14241. a fifth radio frequency signal line; 14242. a third ground line; 14243. a sixth radio frequency signal line; 14244. a third ground plane; 14245. a power layer; 14246. a third ground hole; 1425. the microstrip line is combined with the coplanar waveguide structure; 14251. a fifth radio frequency signal line; 14252. a third ground line; 14253. a sixth radio frequency signal line; 14254. a third ground plane; 14255. a power layer; 14256. a third ground hole; 1426. the microstrip line is combined with the coplanar waveguide structure; 14261. a step-shaped groove; 1427. the microstrip line is combined with the coplanar waveguide structure; 14271. a first groove; 1428. the microstrip line is combined with the coplanar waveguide structure; 14281. a second groove; 143. an antenna; 15. and a power supply module.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the present invention, directional terms such as "up", "down", "front", "back", "left", "right", "inner", "outer", "side", "top" and "bottom" are used only with reference to the orientation of the drawings, and the directional terms are used for illustration and understanding of the present invention, and are not intended to limit the present invention.

The terms "first," "second," and the like in the terms of the invention are used for descriptive purposes only and not for purposes of indication or implication relative importance, nor as a limitation on the order of precedence.

Referring to fig. 1 to 2, fig. 1 is a block diagram of an embodiment of a device control circuit of the present invention, and fig. 2 is a circuit diagram of a camera module of an embodiment of the device control circuit of the present invention.

In the drawings, elements having similar structures are denoted by the same reference numerals.

Referring to fig. 1 to 2, the present invention provides an apparatus control circuit 10, which includes a control chip 11, a camera module 12, an audio module 13, a radio frequency module 14, and a power supply module 15. The power supply module 15 is used for respectively providing the working voltages of the control chip 11, the camera module 12, the audio module 13 and the radio frequency module 14. The power line of the power supply module 15 and the signal line of the audio module 13 need to cross each other, and the power line of the power supply module 15 needs to be far from the signal line of the audio module 13.

Referring to fig. 1 to 2, the camera module 12 is connected to the control chip 11, and the camera module 12 transmits video data and image data to the control chip 11. The camera module 12 includes a camera interface circuit, which includes a clock connection line 122 and a data connection line 123, a camera interface 121, and a camera control chip J9. The camera interface 121 is connected to the camera control chip J9 through a signal line, and the ground pin of the camera control chip J9 is grounded. The clock connection line 122 is used for the camera interface 121 to transmit a clock signal to the camera control chip J9, and the data connection line 123 is used for the camera interface 121 to transmit a data signal to the camera control chip J9. The clock connection line 122 and the data connection line 123 are both high speed signal lines with a set characteristic impedance of 95omh-105ohm and are differential signal lines, which can be used to reduce the effect of noise interference signals. The transmission rates of the clock connection line 122 and the data connection line 123 are both within 2.5 Gbps. Controlling the characteristic impedance of the clock connection line 122 can effectively reduce the reflection of the clock signal and reduce the distortion of the clock signal. Controlling the characteristic impedance of the data link line 123 can effectively reduce the reflection of the data signal, and can reduce the distortion of the data signal.

Referring to fig. 1 to 2, the differential signal lines are two signal lines, and the two signal lines transmit differential signals, and the amplitudes of the two differential signals are the same and the phases of the two differential signals are opposite. The differential signal is detected by a differential amplifier at a receiving end, and the differential amplifier only has the amplification effect on the difference between two paths of input signals. The noise interference signal is usually a common mode signal, which is a pair of signals with equal magnitude and same polarity applied to the differential signal line. In the signal transmission process, noise interference signals are equivalently and simultaneously loaded on the differential signal line, so that the difference value of the noise interference signals is zero, and the noise interference signals do not influence the logic significance of the data signals. Differential signal lines may be used to reduce the effects of noise interference signals. In addition, the differential signal lines are relatively close and have equal signal amplitudes, and the amplitudes of the coupling electromagnetic fields between the differential signal lines and the ground lines are also equal. The differential signal lines can also effectively suppress electromagnetic interference because the electromagnetic fields of the differential signal lines cancel each other out due to the opposite polarities of the signals on the differential signal lines.

Referring to fig. 1 to 2, the length of the clock connection line 122 and the data connection line 123 is a first predetermined value, and the first predetermined value is 100mm to 305 mm. Because the camera interface circuit is an integrated circuit, the length of the line between the clock connection line 122 and the data connection line 123 is 100mm-305mm, which is convenient for the integration of the camera interface circuit. At least two data link lines 123 constitute the data link lines 123 of the same video module. The length difference of the data link lines 123 of the same video module is a second predetermined value, which is 0-1.5 mm. Since the second setting value is 0-1.5mm and the data connection line 123 transmits the data of the same video component, the data transmission speeds of the same video component are consistent, and the data transmission speeds are consistent, thereby reducing errors between the data of the same component. The difference in the length of the data link 123 between the different video modules is a third setting, which is 0-3.3 mm. Since the third setting value is 0-3.3mm, the transmission speeds of the data connection lines 123 of different video components are consistent, and the transmission efficiency of the data connection lines 123 is effectively improved.

Referring to fig. 1 to 2, the spacing between the different clock connecting lines 122 is 1.45 to 1.55 times the line width of the clock connecting lines 122. Because mutual inductance and mutual capacitance between different clock connection lines 122 can cause noise on the lines, setting the spacing between different clock connection lines 122 can reduce noise interference and prevent crosstalk between different clock connection lines 122. The distance between the different data link lines 123 is 1.45-1.55 times the line width of the data link lines 123. Since mutual inductance and mutual capacitance between different data connection lines 123 may cause noise on the lines, setting the spacing between different data connection lines 123 may reduce noise interference, preventing crosstalk between different data connection lines 123.

Referring to fig. 1 to 2, the camera interface circuit further includes an analog portion power supply VCAMA _ PMU, a digital portion power supply VCAMD _ PMU, an input/output power supply VCAM _ IO _ PMU, and an external device power supply VLADO28_ PMU. The analog part power supply VCAMA _ PMU supplies power to an analog circuit of the camera interface circuit, and the digital part power supply VCAMD _ PMU supplies power to a digital circuit of the camera interface circuit. The input/output power supply VCAM _ IO _ PMU supplies power to the input/output part circuit of the camera interface circuit, and the external device power supply VLADO28_ PMU is used for the camera control chip to supply working voltage of the external device. The analog part power supply VCAMA _ PMU and the digital part power supply VCAMD _ PMU are respectively supplied by different low dropout linear voltage regulators. Since the digital part power supply VCAMD _ PMU outputs a signal with dither noise, and the analog device is sensitive to the dither noise of the power supply, the dither noise easily affects the normal operation of the analog device. Therefore, the analog part power supply VCAMA _ PMU and the digital part power supply VCAMD _ PMU are respectively supplied with power through different low dropout regulators, and the noise interference of the analog part power supply VCAMA _ PMU and the digital part power supply VCAMD _ PMU can be avoided.

Referring to fig. 1 to 2, the camera interface circuit includes a first bypass capacitor and a second bypass capacitor. The first bypass capacitor comprises a first bypass capacitor C27, a first bypass capacitor C15, a first bypass capacitor C14 and a first bypass capacitor C22. The second bypass capacitor comprises a second bypass capacitor C26, a second bypass capacitor C25, a second bypass capacitor C24 and a second bypass capacitor C23. A first bypass capacitor C22 and a second bypass capacitor C23 are connected between the digital part power supply VCAMD _ PMU and the ground terminal. A first bypass capacitor C14 and a second bypass capacitor C24 are connected between the input/output power supply VCAM _ IO _ PMU and the ground terminal, and a first bypass capacitor C15 and a second bypass capacitor C25 are connected between the external device power supply VLADO28_ PMU and the ground terminal. A first bypass capacitor C27 and a second bypass capacitor C26 are connected between the analog part supply voltage VCAMA _ PMU and ground. The capacitive reactance of the first bypass capacitor is 4.65 mu F-4.75 mu F, and the capacitive reactance of the second bypass capacitor is 99.5NF-100.5 NF. The first bypass capacitor C27 is connected in parallel with the second bypass capacitor C26, and the first bypass capacitor C15 is connected in parallel with the second bypass capacitor C25. The first bypass capacitor C14 is connected in parallel with the second bypass capacitor C24, and the first bypass capacitor C22 is connected in parallel with the second bypass capacitor C23. The first bypass capacitor and the second bypass capacitor can filter out high-frequency clutter in the camera interface circuit.

Referring to fig. 1 to 2, the camera interface circuit further includes an electrostatic resistor, which includes an electrostatic resistor ESD1, an electrostatic resistor ESD2, and an electrostatic resistor ESD 3. The ESD1 is connected in parallel with the clock data line 123, the ESD2 is connected in parallel with the data connection line 123, and the ESD3 is connected in parallel with the data connection line 123. The electrostatic impedor is internally provided with a TVS diode, and the parasitic capacitance of the TVS diode is 0.5-1.0 pF. The electrostatic resistor is used for electrostatic protection, and sensitive electronic elements in the circuit are easily affected by electrostatic discharge due to static electricity generated on a camera interface circuit. The electrostatic resistor has fast response speed and low capacitance, and the electrostatic resistor can prevent sensitive electronic elements from being influenced by electrostatic discharge.

Referring to fig. 3 and 4, fig. 3 is a circuit diagram of an electret microphone circuit of an earphone module according to an embodiment of an apparatus control circuit of the present invention, and fig. 4 is a circuit diagram of an earphone circuit of an earphone module according to an embodiment of an apparatus control circuit of the present invention.

Please refer to fig. 3 in conjunction with fig. 1. The audio module 13 includes an electret microphone circuit 131 and an earphone circuit 132, the electret microphone circuit 131 is connected in parallel with the earphone circuit 132, and electronic components of the audio module 13 are connected by a signal line. The electret microphone circuit 131 is provided with a microphone input 1311, the microphone input 1311 comprising a microphone input positive pole AU _ VIN _ P and a microphone input negative pole AU _ VIN _ N. A first capacitor C3 is connected between the positive electrode AU _ VIN _ P of the microphone input end and the negative electrode AU _ VIN _ P of the microphone input end, and the capacitive reactance of the first capacitor C3 is 99.5-100.5 pF. An electret microphone MIC is connected between the positive electrode AU _ VIN _ P of the microphone input end and the negative electrode AU _ VIN _ P of the microphone input end in series and is used for sound-electricity conversion. The electret microphone circuit 131 generates an electrical signal by an acousto-electric conversion, which flows to the earphone control chip J4 through the microphone interface HP _ MIC of the earphone circuit 132. A first coupling capacitor C1 and a first inductor L1 are connected in series between the positive electrode AU _ VIN _ P of the microphone input end and the electret microphone MIC, the capacitive reactance of the first coupling capacitor is 0.95 mu F-1.05 mu F, and the first coupling capacitor C1 is used for transmitting alternating current signals. A second coupling capacitor C2 and a second inductor L2 are connected in series between the negative electrode AU _ VIN _ N of the microphone input end and the electret microphone MIC, the capacitive reactance of the second coupling capacitor C2 is 0.95 mu F-1.05 mu F, and the second coupling capacitor C2 is used for transmitting alternating current signals. A first TVS diode ED2 is connected in parallel between the positive electrode AU _ VIN _ P of the microphone input terminal and the electret microphone MIC, a second TVS diode ED1 is connected in parallel between the negative electrode AU _ VIN _ N of the microphone input terminal and the electret microphone MIC, and the first TVS diode ED2 and the second TVS diode ED1 are used for performing rapid overvoltage protection on circuit elements of the electret microphone circuit 131. The signal line of the electret microphone circuit 131 needs to be processed by a package, the signal line can shield the interference signal by the package processing, and the package, that is, the whole signal line is provided with a ground wire around.

Please refer to fig. 3 in conjunction with fig. 1. The electret microphone circuit 131 comprises a first filter capacitor having a capacitive reactance of 32.5-34.5 pF. The first filter capacitor is connected in parallel with the electret microphone circuit 131, and the first filter capacitor is used for filtering out radio frequency interference. The first filter capacitor comprises a first filter capacitor C5 and a first filter capacitor C6, and the distance between the first filter capacitor and the microphone input terminal 1311 is smaller than that between the first filter capacitor and the control chip 11. The first filter capacitor is used for filtering high-frequency interference when the filter operates at 900MHz frequency. A short trace is required between the first filter capacitor and the microphone input 1311, so that the signal passes through the first filter capacitor and then reaches other points, and thus the first filter capacitor can better filter out high-frequency interference. Since there is a radio frequency interference signal on the electret microphone circuit 131, the first filter capacitor can be used to filter out the radio frequency interference signal.

Please refer to fig. 3 in conjunction with fig. 1. The electret microphone interface circuit comprises a power supply micbias o for providing an operating voltage for the electret microphone circuit 131. A first resistor R1 and a second resistor R2 are provided between the power supply micbias and the microphone input 1311, and the first resistor R1 is connected in series with the second resistor R2. The first resistor R1 has a resistance of 0.95-1.05 kOmega, and the second resistor R2 has a resistance of 1.45-1.55 kOmega. A third resistor R3 and a fourth resistor R4 are provided between the microphone input 1311 and the ground, and the third resistor R3 and the fourth resistor R4 are connected in series. The third resistor R3 has a resistance value of 1.45-1.55k omega, and the fourth resistor R4 has a resistance value of 0.95-1.05k omega. The electret microphone circuit 131 includes a second filter capacitor C2, the second filter capacitor C2 is disposed between the power supply micbias and the ground, and the capacitive reactance of the second filter capacitor C2 is 9.5-10.5 pF. The distance between the second filter capacitor C2 and the microphone input terminal 1311 is smaller than the distance between the second filter capacitor C2 and the control chip 11, and the second filter capacitor C2 is used for filtering high-frequency interference when the microphone works at 1800MHz frequency. A short trace is required between the second filter capacitor C2 and the microphone input 1311, so that the signal passes through the second filter capacitor C2 before reaching other points, and thus the first filter capacitor can better filter out high frequency interference. The second filter capacitor C2 may be used to filter out the rf interference signal due to the presence of the rf interference signal on the electret microphone circuit 131. The influence of the radio frequency interference signal generally depends on different designs, and the circuit can select and paste a required filter capacitor according to a test result, even the circuit does not need to select and paste the filter capacitor.

Please refer to fig. 4 in conjunction with fig. 1. The headphone circuit 132 includes a headphone control chip J4, a headphone interface circuit 1323, a microphone interface circuit 1322, a headphone detection circuit 1321, and a headphone antenna input FM _ ANT. The earphone control chip J4 is connected to the earphone interface circuit 1323, the microphone interface circuit 1322, the earphone detection circuit 1321, and the earphone antenna input terminal FM _ ANT, respectively. The earphone detection circuit 1321 is configured to detect insertion and extraction of an earphone, and the earphone detection circuit 1321 includes an earphone detection interface HP _ accset, a first magnetic bead B6, and a fifth resistor R9. The first magnetic bead B6 is connected in series between the headphone detection interface HP _ accset and the headphone control chip J4, and the fifth resistor R9 is connected in series between the headphone detection interface HP _ accset and the headphone control chip J4. The microphone interface circuit 1323 includes a microphone interface HP _ MIC and a second magnetic bead B8, and the second magnetic bead B8 is connected in series between the microphone interface HP _ MIC and the earphone control chip J4. The first bead B6 and the second bead B8 can suppress high frequency interference and spike interference on the signal line, and the first bead B6 and the second bead B8 can also suppress electromagnetic interference on the signal line. A third inductor L3 is arranged between the earphone antenna input end FM _ ANT and the grounding end, and the inductive reactance of the third inductor L3 is 99.5-100.5 NH.

Please refer to fig. 4 in conjunction with fig. 1. The headphone interface circuit 1323 comprises a headphone interface, a third filter capacitor comprising a third filter capacitor C32 and a third filter capacitor C31. The third filter capacitor is connected in parallel with the earphone circuit 132, and the distance between the third filter capacitor and the earphone interface is smaller than the distance between the third filter capacitor and the control chip 11. The capacitance reactance of the third capacitor is 32.5-33.5pF, and the third filter capacitor can be used for better filtering radio frequency interference. Due to the presence of the radio frequency interference signal on the earphone circuit, the third filter capacitor can be used for filtering the radio frequency interference signal. The third filter capacitor can be selected and pasted according to a test result, and even the third filter capacitor does not need to be selected and pasted under certain conditions.

On the basis of fig. 1, please refer to fig. 4, the earphone interface circuit includes an earphone interface and a magnetic bead. The earphone interface comprises an earphone left channel interface AU _ HPL and an earphone right channel interface AU _ HPR. The distance between the magnetic bead and the earphone interface is smaller than the distance between the magnetic bead and the control chip 11, and the magnetic bead can be used for better inhibiting noise interference on an earphone circuit. The magnetic beads comprise a third magnetic bead B9, a fourth magnetic bead B10, a fifth magnetic bead B12 and a sixth magnetic bead B13. The third magnetic bead B9 and the fourth magnetic bead B10 are connected in series between the headphone left channel interface AU _ HPL and the headphone control chip J4, and the fifth magnetic bead B12 and the sixth magnetic bead B13 are connected in series between the headphone right channel interface AU _ HPR and the headphone control chip J4. The third magnetic bead B9 and the fourth magnetic bead B10 can suppress high-frequency interference and spike interference in a signal line, and the third magnetic bead B9 and the fourth magnetic bead B10 can also suppress electromagnetic interference in the signal line. The fifth bead B12 and the sixth bead B13 can suppress high frequency interference and spike interference on the signal line, and the fifth bead B12 and the sixth bead B13 can also suppress electromagnetic interference on the signal line.

On the basis of fig. 1, please refer to fig. 4, the earphone module includes a third TVS diode VR7, a fourth TVS diode VR4, a fifth TVS diode VR5, and a sixth TVS diode VR 6. The third TVS diode VR7 is connected in parallel to the headphone detection circuit 1321, and the fourth TVS diode VR4 is connected in parallel to the microphone interface circuit 1322. The fifth TVS diode VR5 is connected in parallel to the headset interface circuit 1323 and the sixth TVS diode VR6 is connected in parallel to the headset interface circuit 1323. The third TVS diode VR7 is used for fast overvoltage protection of the circuit elements of the earphone detection circuit 1321. The fourth TVS diode VR4 is used for fast over-voltage protection of the circuit elements of the microphone interface circuit 1322, and the fifth TVS diode VR5 and the sixth TVS diode VR6 are used for fast over-voltage protection of the circuit elements of the headset interface circuit 1323. A sixth resistor R10 is connected between the earphone interface circuit 132 and the ground, a seventh resistor R11 is connected between the earphone interface circuit 132 and the ground, and the sixth resistor R10 is connected in parallel with the seventh resistor R11.

Referring to fig. 5, fig. 5 is a circuit diagram of a radio frequency module according to an embodiment of the device control circuit of the present invention.

On the basis of fig. 1, please refer to fig. 5, the rf module 14 is connected to the control chip 11. The rf module 14 is configured to receive a radio signal and transmit the radio signal to the control chip 11, and the rf module 14 is configured to transmit a wired electrical signal of the control chip 11. The rf module 14 includes an rf circuit, which includes an rf signal line 142, an rf control chip 141 and an antenna 143. The rf signal line 142 is used for bidirectional transmission of rf signals between the antenna 143 and the rf control chip 141. A first pi matching circuit is connected between the radio frequency control chip 141 and the antenna Main, and circuit elements of the first pi matching circuit are a fifth resistor R7, a second capacitor C7 and a third capacitor C8. And a second pi matching circuit is connected between the radio frequency control chip and the antenna DRX, and circuit elements of the second pi matching circuit are a sixth resistor R8, a fourth capacitor C9 and a fifth capacitor C10. The pi matching circuit may suppress harmonic components and interference outside the operating frequency of the antenna 143, the pi matching circuit may be used for impedance matching, and the pi matching circuit may transfer signal power to the antenna. The antenna 143 needs to be far away from the audio module 13, and the distance between the antenna 143 and the audio module 13 can reduce the radiation interference of the antenna 143 on the audio module 13.

Referring to fig. 6, fig. 6 is a schematic diagram of a microstrip line structure according to an embodiment of the device control circuit of the present invention.

Referring to fig. 6, the microstrip line structure 1421 is a two-layer PCB microstrip line structure, and the microstrip line structure 1421 can be used to control the characteristic impedance of the rf signal line 142. The microstrip line structure 1421 includes a first ground hole 14213, a first rf signal line 14211, a first ground layer 14212, and a prepreg, wherein the first ground layer 14212 is disposed on a second layer of the two-layer PCB microstrip line structure. The first rf signal line 14211 is disposed in the middle of the first layer of the microstrip line structure 1421, and the prepreg is disposed between the first rf signal line and the first ground layer. The prepreg mainly comprises resin and a reinforcing material, and is an insulating material. The first ground hole 14213 is disposed between the first rf signal line 14211 and the first ground layer 14212, and the first ground hole 14213 can improve the rf performance of the microstrip line structure 1421. The distance between the first ground hole 14213 and the first rf signal line 14211 in the horizontal direction is at least twice the line width of the first rf signal line 14211, the distance between the first rf signal line 14211 and the first ground layer 14212 is the height of the reference ground plane, and the microstrip line structure 1421 can effectively transmit high frequency signals. The microstrip line structure 1421 can control the thickness and width of the first rf signal line 14211, and the microstrip line structure 1421 can also control the distance between the first rf signal line 14211 and the first ground layer 14212, so the characteristic impedance of the microstrip line structure 1421 can also be controlled and kept unchanged.

Referring to fig. 7, fig. 7 is a schematic diagram of a coplanar waveguide structure according to an embodiment of the device control circuit of the present invention.

Referring to fig. 7, the coplanar waveguide structure 1422 is a two-layer PCB coplanar waveguide structure, and the coplanar waveguide structure 1422 can control the characteristic impedance of the rf signal line 142. The coplanar waveguide structure 1422 includes a first ground line 14221, a second rf signal line 14222, a reference ground 14223, and a prepreg, where the second rf signal line is disposed in the middle of the first layer of the coplanar waveguide structure of two layers of PCB boards. The reference ground is arranged on the second layer of the two-layer PCB coplanar waveguide structure, and the prepreg is arranged between the first radio frequency signal line and the first ground layer. The prepreg mainly comprises resin and a reinforcing material, and is an insulating material. The first ground 14221 is disposed at two ends of the second rf signal 14222, a distance between the first ground 14221 and the second rf signal 14222 is a ground gap, and a distance between the first ground 14221 and the reference ground 14223 is a height of the reference ground plane. The first ground line 14221 may be used for shielding interference, and the coplanar waveguide structure 1422 may control the impedance of the circuit by adjusting the distance between the second rf signal line 14222 and the first ground line 14221. The coplanar waveguide structure 1422 can control the impedance of the circuit by adjusting the line width of the second rf signal line 14222, and the coplanar waveguide structure 1422 can control the impedance of the circuit by adjusting the distance between the second rf signal line 14222 and the reference ground 14223. Thus, the characteristic impedance of coplanar waveguide structure 1422 is also controllable and invariant.

When two sets of rf signal lines transmit signals, the microstrip line and the coplanar waveguide structure 1423 may be configured as a three-layer PCB structure. The microstrip line-combined coplanar waveguide structure 1423 includes a coplanar waveguide including a third radio frequency signal line 14231 and a second ground 14232, and a microstrip line. The third rf signal line 14231 is disposed in the middle of the first layer of the microstrip-line-coplanar waveguide structure 1423, the second ground 14232 is disposed at two ends of the third rf signal line 14231, and the distance between the second ground 14232 and the third rf signal line 14231 is set as a gap to ground. The microstrip line in combination with the coplanar waveguide structure 1423 can control the impedance of the circuit by adjusting the distance between the third rf signal line 14231 and the second ground 14232. The microstrip line combined with the coplanar waveguide structure 1423 can control the impedance of the circuit by adjusting the line width of the third rf signal line 14231, and the microstrip line combined with the coplanar waveguide structure can control the characteristic impedance of the circuit by adjusting the distance between the third rf signal line 14231 and the second ground 14232. The microstrip line in combination with the coplanar waveguide structure 1423 can also adjust the distance between the third rf signal line 14231 and the second ground layer 14234 to control the characteristic impedance of the circuit.

The microstrip line is disposed on the second layer and the third layer, and includes a fourth rf signal line 14233, a second ground hole 14236, a second ground layer 14234, and a second ground hole 14235. The fourth rf signal line 14233 is disposed on the second layer of the microstrip-line combined coplanar waveguide structure 1423, and the second ground layer 14234 is disposed on the third layer of the microstrip-line combined coplanar waveguide structure 1423. The second via 14235 is disposed between the fourth rf signal line 14233 and the second ground layer 14234, a horizontal distance between the second via 14235 and the fourth rf signal line 14233 is at least twice a line width of the third rf signal line 14231, and a distance between the third rf signal line 14231 and the second ground layer 14234 is a height of the reference ground plane. The radio frequency signal is transmitted through the coplanar waveguide, and the radio frequency signal can be shielded and interfered by the ground wire. Radio frequency signals can also be transmitted through the microstrip line and shielded from interference through the ground hole. The microstrip line combined with the coplanar waveguide 1423 can control the thickness and width of the fourth rf signal line 14233, and the microstrip line combined with the coplanar waveguide 1423 can also control the distance between the fourth rf signal line 14233 and the second ground layer 14234. Since the characteristic impedance of the circuit is related to the thickness and width of the fourth rf signal line 14233, and the characteristic impedance of the circuit is also related to the distance between the fourth rf signal line 1423 and the second ground layer 14234, the characteristic impedance of the microstrip line in combination with the coplanar waveguide structure 1423 can be controlled and unchanged.

Referring to fig. 9, fig. 9 is a schematic diagram of a microstrip line combined with a coplanar waveguide structure of an apparatus control circuit according to a second embodiment of the present invention.

Referring to fig. 9, when two sets of rf signal lines transmit signals and the rf signal lines need to shield interference of a power source, the microstrip line and the coplanar waveguide structure 1424 are combined to form a four-layer PCB structure. The microstrip line combined coplanar waveguide structure comprises a coplanar waveguide and a microstrip line. The coplanar waveguide is disposed on a first layer of the microstrip-line-combined coplanar waveguide structure 1424, and the coplanar waveguide includes a fifth radio frequency signal line 14241 and a third ground line 14242. The fifth rf signal line 14241 is disposed in the middle of the first layer of the microstrip-line combined coplanar waveguide structure 1424, the third ground line 14242 is disposed at two ends of the fifth rf signal line 14241, and the distance between the third ground line 14242 and the third rf signal line 14231 is a gap to ground. The microstrip line in combination with the coplanar waveguide structure 1424 can control the impedance of the circuit by adjusting the distance between the fifth rf signal line 14241 and the third ground line 14242. The microstrip line combined with the coplanar waveguide 1424 can control the impedance of the circuit by adjusting the line width of the third rf signal line 14241, and the microstrip line combined with the coplanar waveguide 1423 can control the characteristic impedance of the circuit by adjusting the distance between the fifth rf signal line 14241 and the third ground line 14242. The microstrip line in combination with the coplanar waveguide structure 1424 can also control the characteristic impedance of the circuit by adjusting the distance between the fifth rf signal line 14231 and the third ground layer 14244.

The microstrip line is disposed on the second layer, the third layer, and the fourth layer, and includes a sixth rf signal line 14243, a third ground via 14246, a third ground plane 14244, and a power plane 14245. And prepregs are arranged between the layers, mainly comprise resin and reinforcing materials, and are insulating materials. The sixth rf signal line 14243 is disposed on the second layer of the microstrip-line combined coplanar waveguide structure 1424, and the third ground layer 14244 is disposed on the third layer of the microstrip-line combined coplanar waveguide structure 1424. The power layer 14235 is disposed on the fourth layer of the microstrip-line combined coplanar waveguide structure 1423, and the third ground hole 14236 is disposed between the sixth rf signal line 14243 and the third ground layer 14244. The horizontal distance between the third ground hole 14246 and the sixth rf signal line 14243 is at least twice the line width of the fifth rf signal line 14241, and the distance between the sixth rf signal line 14243 and the third ground layer 14244 is the height of the reference ground plane. The radio frequency signal can be transmitted through the coplanar waveguide, and the radio frequency signal can be shielded by the ground wire. Or the radio frequency signal can be transmitted through the microstrip line, and the radio frequency signal can shield interference through the ground hole. The microstrip line in combination with the coplanar waveguide 1424 can control the thickness and width of the sixth rf signal line 14243, and the microstrip line in combination with the coplanar waveguide 1424 can also control the distance between the sixth rf signal line 14243 and the third ground layer 14244. Since the characteristic impedance of the circuit is related to the thickness and width of the sixth rf signal line 14243, and the characteristic impedance of the circuit is also related to the distance between the sixth rf signal line 14243 and the third ground layer 14244, the characteristic impedance of the microstrip line in combination with the coplanar waveguide structure 1424 can be controlled to be constant. Since the power plane 14245 is disposed inside the four-layer PCB, the power plane 14245 is far away from the fifth rf signal line 14241 and the sixth rf signal line 14243, and a prepreg having an insulating structure is disposed between the power plane and the fifth rf signal line 14241, and between the power plane and the sixth rf signal line 14243. Therefore, the microstrip line combined with the coplanar waveguide structure 1424 can effectively shield the interference of the power supply to the radio frequency signal line.

Fig. 10 is a schematic diagram of a third embodiment of a microstrip line in combination with a coplanar waveguide structure of the device control circuit of the present invention.

Referring to fig. 10, when two sets of rf signal lines transmit signals and the rf signal lines need to shield the interference of the power source, the microstrip line and the coplanar waveguide structure 1425 form a four-layer PCB structure. The microstrip line combined coplanar waveguide structure comprises a coplanar waveguide and a microstrip line. The coplanar waveguide is disposed on a first layer of the microstrip-line-combined coplanar waveguide structure 1425, and the coplanar waveguide includes a fifth rf signal line 14251 and a third ground line 14252. The fifth rf signal line 14251 is disposed in the middle of the first layer of the microstrip-line combined coplanar waveguide structure 1425, the third ground line 14252 is disposed at two ends of the fifth rf signal line 14251, and the distance between the third ground line 14252 and the fifth rf signal line 14251 is a gap to ground. The microstrip line in combination with the coplanar waveguide structure 1423 can control the impedance of the circuit by adjusting the distance between the fifth rf signal line 14251 and the third ground line 14252. The microstrip line combined with the coplanar waveguide structure 1425 can control the impedance of the circuit by adjusting the line width of the fifth rf signal line 14251, and the microstrip line combined with the coplanar waveguide structure 1425 can control the impedance of the circuit by adjusting the distance between the fifth rf signal line 14251 and the third ground layer 14254. The microstrip line in combination with the coplanar waveguide structure 1423 can also control the characteristic impedance of the circuit by adjusting the distance between the fifth rf signal line 14253 and the third ground plane 14254.

The microstrip line is disposed on the second layer, the third layer, and the fourth layer, and includes a sixth rf signal line 14253, a third ground via 14256, a third ground plane 14254, and a power plane 14255. And prepregs are arranged among the layers, mainly comprise resin and reinforcing materials, and can be used for insulating signal lines. The sixth rf signal line 14253 is disposed on the second layer of the microstrip-line combined coplanar waveguide structure 1425, and the third ground layer 14254 is disposed on the fourth layer of the microstrip-line combined coplanar waveguide structure 1425. The power layer 14255 is disposed on the third layer of the microstrip-line combined coplanar waveguide structure 1425. Because the power layer is disposed on the third layer of the microstrip-combined coplanar waveguide structure 1425, and the rf signal lines are disposed on the first layer and the second layer of the microstrip-combined coplanar waveguide structure 1425, the power layer is convenient for providing the operating voltage of the four layers of PCB. The third ground hole 14256 is disposed between the fourth rf signal line and the third ground layer 14254. The horizontal distance between the third ground hole 14256 and the sixth rf signal line 14253 is at least twice the line width of the fifth rf signal line 14251, and the distance between the sixth rf signal line 14253 and the third ground layer 14254 is the height of the reference ground plane. Radio frequency signals can be transmitted through the coplanar waveguide, and the radio frequency signals can be shielded by the ground wire. Or the radio frequency signal can be transmitted through the microstrip line, and the radio frequency signal can shield interference through the ground hole. The microstrip line combined with the coplanar waveguide structure 1425 can control the thickness and width of the sixth rf signal line 14253, and the microstrip line combined with the coplanar waveguide structure 1425 can also control the distance between the sixth rf signal line 14233 and the third ground plane 14254. since the characteristic impedance of the circuit is related to the thickness and width of the sixth rf signal line 14253, and the characteristic impedance of the circuit is related to the distance between the sixth rf signal line 14253 and the third ground plane 14254, the characteristic impedance of the microstrip line combined with the coplanar waveguide structure 1425 can also be controlled to be constant. Since the power plane 14255 is disposed inside the four-layer PCB, a prepreg having an insulating structure is disposed between the power plane and the fifth and sixth

rf signal lines

14251, 14253. Therefore, the microstrip line combined with the coplanar waveguide structure 1425 can effectively shield the interference of the power supply to the radio frequency signal line.

Referring to fig. 8 to 10, the microstrip line combined coplanar waveguide structure includes a coplanar waveguide and a microstrip line. The coplanar waveguide and the microstrip line can simultaneously transmit two paths of signals. Compared with the coplanar waveguide, the microstrip line has higher dispersion and higher radiation loss. If the transmitted signal requires low dispersion or the transmitted signal requires low loss, the signal should be transmitted using coplanar waveguides. The coplanar waveguide has a relatively thick dielectric layer and has poor thermal conductivity, so that the coplanar waveguide is not favorable for realizing a high-power amplifier. The microstrip line combined coplanar waveguide structure comprises a microstrip line and a coplanar waveguide, the microstrip line can be used for the radio frequency signal line 142 in the high-power amplifier, and the coplanar waveguide can be used for the rest radio frequency signal lines 142.

Fig. 11 is a second schematic diagram of the microstrip line of the device control circuit of the present invention combined with the groove of the coplanar waveguide structure according to the second embodiment.

Referring to fig. 11, the microstrip line combined coplanar waveguide structure 1426 includes a groove. The groove comprises a first side edge and a second side edge, and the length of the first side edge of the groove is greater than that of the second side edge of the groove. The bottom of the recess may be stepped, and the recess is a stepped recess 14261. The stepped recess 14261 is disposed at the lower end of the fifth rf signal line 14241 and the third ground line 14242, and the stepped recess 14261 is disposed between the first layer and the second layer. As the coplanar waveguide has dielectric loss, the grooves are arranged on the prepreg, the dielectric loss caused by the prepreg can be reduced, and the quality of signals transmitted by the coplanar waveguide is better. Since the grooves are formed in the prepreg, the mechanical strength of the microstrip line combined with the coplanar waveguide is reduced, and the microstrip line combined with the coplanar waveguide is easily damaged. The deeper the depth of the groove, the lower the mechanical strength of the microstrip line in combination with the coplanar waveguide. Therefore, if a deeper groove is designed, the mechanical strength of the microstrip line combined with the coplanar waveguide will be lower. The larger the width of the groove, the lower the mechanical strength of the microstrip line in combination with the coplanar waveguide. Therefore, if a wider groove is required, the mechanical strength of the microstrip line combined with the coplanar waveguide will be lower. The stepped groove 14261 can reduce transmission loss of the coplanar waveguide, and the stepped groove 14261 can ensure high strength of the microstrip line combined coplanar waveguide structure.

Fig. 12 is a third schematic diagram of the microstrip line of the device control circuit of the present invention in combination with the groove of the coplanar waveguide structure according to the second embodiment.

The microstrip line in combination with the coplanar waveguide structure 1427 includes a groove, the bottom of which may be arc-shaped. The arc of the arc shape is a minor arc recessed in a groove, which is the first groove 14271. The first groove 14271 is disposed at the lower end of the fifth rf signal line 14241 and the third ground line 14242, and the first groove 14271 is located between the first layer and the second layer of the microstrip-line combined coplanar waveguide structure 1427. The first groove 14271 can reduce the transmission loss of the coplanar waveguide, and the first groove 14271 can ensure the microstrip line to be combined with the coplanar waveguide structure 1427 with high strength.

Fig. 13 is a fourth schematic diagram of a microstrip line of the device control circuit of the present invention combined with a groove of the coplanar waveguide structure.

The microstrip line in combination with coplanar waveguide structure 1428 coplanar waveguide includes a groove, the bottom of which can be arc-shaped. The arc of the arc is a minor arc protruding from the groove, which is the second groove 14281. The second recess 14281 is disposed at the lower end of the fifth rf signal line 14241 and the third ground line 14242, and the second recess 14281 is located between the first layer and the second layer of the microstrip-line combined coplanar waveguide structure 1428. The second groove 14281 can reduce the transmission loss of the coplanar waveguide, and the second groove can ensure the microstrip line to be combined with the coplanar waveguide structure 1428 with high strength.

Referring to fig. 10 to 13, compared to the arc-shaped groove, the stepped groove 14261 is easier to manufacture, so the manufacturing cost of the stepped groove 14261 is lower. The second recess 14281 is easier to manufacture than the first recess 14271. When the microstrip line and the coplanar waveguide structure are subjected to external force, the force applied to the first groove 14271 is more uniform, so that the first groove 14271 can ensure that the strength of the microstrip line and the coplanar waveguide structure is better compared with the stepped groove 14261 and the second groove 14281 of the first groove 14271.

The working principle of the invention is as follows: when the device control circuit 10 is in operation, the power supply module 15 provides operating voltages for the control chip 11, the camera module 12, the audio module 13, and the radio frequency module 14, respectively. When the camera module 12 works, the camera interface 121 transmits signals to the camera control chip J9 through the signal lines. The clock connection line 122 is used for the camera interface 121 to transmit a clock signal to the camera control chip J9, and the data connection line 123 is used for the camera interface to transmit a data signal to the camera control chip J9.

In order to reduce the influence of noise interference signals, the clock connection line 122 and the data connection line 123 are both provided as differential signal lines. At least two data link lines 123 constitute the data link lines 123 of the same video module. The length difference of the data link 123 of the same video module is a second predetermined value, and the second predetermined value is 0-1.5 mm. The difference in the length of the data link lines 123 between the different video modules is a third predetermined value, which is 0-3.3 mm. The clock connection line 122 and the data connection line 123 are high-speed signal lines with characteristic impedance. The line length of the clock connection line 122 and the data connection line 123 is a first set value, and the first set value is 100-305 mm. In order to control the characteristic impedance of the clock connection line 122 and the data connection line 123, the characteristic impedance of the clock connection line 122 and the data connection line 123 are both 95omh-105 ohm. In order to prevent crosstalk between different clock connection lines 122, the spacing between different clock connection lines 122 is 1.45-1.55 times the line width of the clock connection lines 122. In order to prevent crosstalk between the different data link lines 123, the pitch between the different data link lines 123 is 1.45 to 1.55 times the line width of the data link lines 123.

In order to carry out electrostatic protection on the camera interface circuit, an electrostatic impedor is arranged on the camera interface circuit, and a TVS diode is arranged inside the electrostatic impedor. In order to avoid noise interference of the digital section power supply VCAMD _ PUM on the analog section circuit VCAMA _ PUM, the analog section power supply VCAMA _ PUM and the digital section power supply VCAMD _ PUM are supplied by different low dropout linear regulators, respectively. The camera control chip J9 performs analog-to-digital conversion on the received signal, and then the camera control chip J9 transmits video data and image data to the control chip 11.

When the audio module 13 is in operation, the microphone input 1311 of the electret microphone circuit 131 inputs audio data, and the audio data flows to the control chip 11 through the signal line. Since the electret microphone circuit 131 has radio frequency interference, the electret microphone circuit 131 is provided with a first filter capacitor and a second filter capacitor C2. The distance between the first filter capacitor and the microphone input terminal 1311 is smaller than the distance between the first filter capacitor and the control chip 11, and the distance between the second filter capacitor C2 and the microphone input terminal 1311 is smaller than the distance between the second filter capacitor C2 and the control chip 11. The first filter capacitor and the second filter capacitor C2 are used for filtering out radio frequency interference. Subsequently, the control chip 11 receives audio data.

When the audio module 13 is in operation, the control chip 11 transmits audio data to the headphone circuit 132. The audio data flows to the earphone interface through the earphone circuit, and because the earphone circuit 132 has radio frequency interference, the earphone circuit 132 is provided with a third filter capacitor. The distance between the third filter capacitor and the earphone interface is smaller than the distance between the third filter capacitor and the control chip 11, and the third filter capacitor can be used for filtering radio frequency interference. In order to suppress noise interference on the earphone circuit 132, a magnetic bead is connected in series on the earphone circuit 132, and a distance between the magnetic bead and the earphone interface is smaller than a distance between the magnetic bead and the control chip 11. Then, the headphone circuit 132 performs an acousto-electric conversion of the received audio signal, and then the headphone emits sound.

When the rf module 14 is in operation, the antenna 143 receives wireless signals. The received signal flows to the rf control chip 141 through the rf signal line 142, and then the rf control chip 141 transmits the signal to the control chip 11. The rf control chip 141 receives the wired signal from the control chip 11, the received signal flows to the antenna 143 through the rf signal line 142, and the antenna 143 transmits the signal. To control the characteristic impedance of the rf signal line 142 to be 49.5-50.5 omega. The structure of the rf signal line 142 may be a microstrip line structure 1421, a coplanar waveguide structure 1422, or a microstrip line combined coplanar waveguide structure. The microstrip line combined coplanar waveguide structure comprises a coplanar waveguide and a microstrip line, wherein radio frequency signals can be transmitted through the coplanar waveguide, and the radio frequency signals are shielded and interfered by a ground wire. Or the radio frequency signal is transmitted through the microstrip line, and the radio frequency signal shields interference through the ground hole.

In order to reduce transmission loss and ensure that the strength of the microstrip line combined with the coplanar waveguide structure is higher, the coplanar waveguide is provided with a groove. The groove is disposed at the lower ends of the third ground line 14242 and the fifth rf signal line 14241, and the groove is located between the first layer and the second layer of the microstrip line-coplanar waveguide structure. The length of the first side edge of the groove is greater than that of the second side edge of the groove, and the bottom of the groove is in a step shape or is in an arc shape. The arc of the arc type is a minor arc which protrudes out of the groove or is recessed in the groove. The groove with the stepped bottom is a stepped groove 14261, and the groove with the curved bottom is a first groove 14271 and a second groove 14281.

Compared with the prior art, the invention has the beneficial effects that: the present invention provides a device control circuit 10, wherein a radio frequency signal line 142 of the device control circuit 10 has characteristic impedance. The device control circuit 10 is based on different circuit structures, and the structure of the radio frequency signal line 142 of the device control circuit 10 can be a microstrip line structure 1421, a coplanar waveguide structure 1422 or a microstrip line combined coplanar waveguide structure, so that the technical problem that the impedance of the existing transmission line is easy to change is effectively solved.

The microstrip line combined coplanar waveguide structure comprises a groove, the groove is arranged at the lower ends of the fifth radio-frequency signal line and the second ground wire, and the groove is positioned between the first layer and the second layer of the microstrip line combined coplanar waveguide structure. The bottom of the groove is in a step shape or an arc shape, and the transmission loss can be reduced by the groove. Meanwhile, the stepped groove 14261 can ensure that the strength of the microstrip line combined coplanar waveguide structure is high, and the arc-shaped first groove 14271 and the arc-shaped second groove 14281 can also ensure that the strength of the microstrip line combined coplanar waveguide structure is high.

The camera interface circuit is provided with a clock connection line 122 and a data connection line 123, and the clock connection line 122 and the data connection line 123 are both high-speed signal lines with characteristic impedance and are differential signal lines. The line length of the clock connection line 122 and the data connection line 123 is a first set value, and the first set value is 100mm and 305 mm. At least two data connection lines 123 constitute the data connection lines 123 of the same video module, and the length difference of the data connection lines 123 of the same video module is a second set value, and the second set value is 0-1.5 mm. The difference in the length of the data link 123 between the different video modules is a third setting, which is 0-3.3 mm. The noise interference signals are equivalently and simultaneously loaded on the differential signal lines, so that the noise interference signal difference is zero, and the noise interference signals do not influence the logic significance of the data signals. Differential signal lines may be used to reduce the effects of noise interference signals.

The audio module 13 includes an electret microphone circuit 131 and an earphone circuit 132, and the electret microphone circuit 131 is provided with a first filter capacitor and a second filter capacitor C2. The distance between the first filter capacitor and the microphone input 1311 is smaller than the distance between the first filter capacitor and the control chip 11, and the distance between the second filter capacitor C2 and the microphone input 1311 is smaller than the distance between the second filter capacitor C2 and the control chip 11. The earphone circuit 132 is provided with a third filter capacitor, and the distance between the third filter capacitor and the earphone interface is smaller than the distance between the third filter capacitor and the control chip 11. The first filter capacitor, the second filter capacitor C2 and the third filter capacitor can better filter radio frequency interference. The last series connection of earphone circuit has the magnetic bead, and the distance of magnetic bead and earphone interface is less than magnetic bead and control chip 11's distance, and the magnetic bead can suppress noise jamming on earphone circuit 132 better.

In summary, although the present invention has been described with reference to the preferred embodiments, the above-described preferred embodiments are not intended to limit the present invention, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, therefore, the scope of the present invention shall be determined by the appended claims.

Claims

1. A radio frequency module is characterized by being used for receiving radio signals and sending wired electric signals and comprising a radio frequency circuit, wherein the radio frequency circuit is provided with a radio frequency signal line, a radio frequency control chip and an antenna, the radio frequency signal line is used for bidirectional transmission of radio frequency signals between the antenna and the control chip, the radio frequency signal line has characteristic impedance, and the radio frequency signal line is in a micro-strip line structure, a coplanar waveguide structure or a micro-strip line combined coplanar waveguide structure based on different circuit structures;

2. The RF module of claim 1, wherein the microstrip line structure is a two-layer PCB microstrip line structure, the two-layer PCB microstrip line structure includes a first ground via, a first RF signal line, and a first ground layer, the first ground layer is disposed on a second layer of the two-layer PCB microstrip line structure, the first RF signal line is disposed in a middle portion of a first layer of the two-layer PCB microstrip line structure, the first ground via is disposed between the first RF signal line and the first ground layer, a horizontal distance between the first ground via and the first RF signal line is at least twice a line width of the first RF signal line, and a distance between the first RF signal line and the first ground layer is a height of a reference ground plane.

3. The RF module of claim 1, wherein the coplanar waveguide structure comprises a two-layer PCB coplanar waveguide structure, the two-layer PCB coplanar waveguide structure comprises a first ground line, a second RF signal line, and a reference ground, the second RF signal line is disposed in the middle of a first layer of the two-layer PCB coplanar waveguide structure, the reference ground is disposed in a second layer of the two-layer PCB coplanar waveguide structure, the first ground line is disposed at two ends of the second RF signal line, a distance between the first ground line and the second RF signal line is a ground gap, and a distance between the first ground line and the reference ground is a height of the reference ground plane.

4. An apparatus control circuit, comprising:

the radio frequency module of any one of claims 1-3;

5. The device control circuit according to claim 4, wherein the device control circuit with the RF module further comprises a camera module, the camera module is connected to the control chip, the camera module is configured to transmit video data and image data to the control chip, the camera module is further connected to the power supply module, and the power supply module is configured to provide an operating voltage of the camera module.

6. The device control circuit according to claim 5, wherein the camera module comprises a camera interface circuit, the camera interface circuit comprises a clock connection line and a data connection line, a camera interface, and a camera control chip, the clock connection line is used for the camera interface to transmit a clock signal to the camera control chip, and the data connection line is used for the camera interface to transmit a data signal to the camera control chip; the clock connecting line and the data connecting line are high-speed signal lines with set characteristic impedance and are differential signal lines, the line length of the clock connecting line and the data connecting line is a first set value, at least two data connecting lines form the data connecting line of the same video assembly, the length difference of the data connecting line of the same video assembly is a second set value, and the length difference of the data connecting lines between different video assemblies is a third set value.

7. The device control circuit according to claim 6, wherein the camera interface circuit comprises an analog part power supply and a digital part power supply, and the analog part power supply and the digital part power supply are respectively supplied with power through different low dropout linear regulators.

8. The device control circuit according to claim 4, wherein the device control circuit with the RF module further comprises an audio module, the audio module is connected to the control chip, the audio module is configured to transmit audio data to the control chip and receive audio data from the control chip, the audio module is further connected to the power supply module, and the power supply module is configured to connect to a working voltage of the audio module.

9. The device control circuit of claim 8, wherein the audio module comprises an electret microphone circuit and an earphone circuit, the electret microphone circuit is connected with the earphone circuit in parallel, the electret microphone circuit comprises a microphone input end, a first filter capacitor and a second filter capacitor, the first filter capacitor and the second filter capacitor are used for filtering radio frequency interference, the first filter capacitor is connected with the electret microphone circuit in parallel, the second filter capacitor is connected with the electret microphone circuit in parallel, the distance between the first filter capacitor and the input end of the microphone is smaller than the distance between the first filter capacitor and the control chip, the distance between the second filter capacitor and the microphone input end is smaller than the distance between the second filter capacitor and the control chip; the earphone circuit comprises an earphone interface and a third filter capacitor, the third filter capacitor is used for filtering radio frequency interference, the third filter capacitor is connected with the earphone circuit in parallel, and the distance between the third filter capacitor and the earphone interface is smaller than that between the third filter capacitor and the control chip.

10. The device control circuit of claim 9, wherein a magnetic bead is connected in series to the earphone circuit, and a distance between the magnetic bead and the earphone interface is smaller than a distance between the magnetic bead and the control chip.