A short-range communication circuit based on the Internet of Things

Abstract

This utility model discloses a short-range communication circuit based on the Internet of Things (IoT), belonging to the field of communication circuit technology. It includes a communication chip, a fourth inductor, a second antenna mounting bracket, and a first antenna. One antenna port of the communication chip is connected to the fourth inductor, which is connected to both the second antenna mounting bracket and the first antenna. A third contact is provided at one end of the fourth inductor. Impedance matching of the antenna is achieved through the fourth inductor. A second antenna mounting bracket is pre-installed in the circuit, allowing for external connection of a second antenna if the first antenna is not compatible or does not meet installation requirements. The antenna in use can be tested by connecting the detection terminal of an external testing device to the third contact and ground. This design meets diverse antenna installation needs at a lower cost, improving the applicability of the short-range communication circuit and its circuit board, and facilitating antenna performance testing.

Description

Technical Field

[0001] This utility model relates to the field of communication circuit technology, specifically to a short-range communication circuit based on the Internet of Things. Background Technology

[0002] Zigbee is a common short-range communication technology used for short-distance and low-data-rate applications. Short-range communication circuits are primarily used for data transmission between various electronic devices with short distances, low power consumption, and low transmission rates, as well as applications involving periodic, intermittent, and low-response-time data transmission. It is a commonly used technology in the Internet of Things (IoT).

[0003] Current short-range communication circuits typically use a single antenna per chip. For example, CN217985425U discloses a smart home gateway that uses a single antenna for both Zigbee and Z-wave wireless communication protocols. This technology allows simultaneous connection of smart home devices using both protocols. However, when the antenna is damaged or its power is insufficient for the intended use case, it is necessary to replace it with a different model of short-range communication circuit; or even replace the entire gateway or electronic device. This results in excessively high configuration costs for short-range communication networks. Utility Model Content

[0004] In view of the above-mentioned technical problems existing in the prior art, this utility model provides a short-range communication circuit based on the Internet of Things, which facilitates antenna adjustment and keeps the configuration cost low.

[0005] This utility model discloses a short-range communication circuit based on the Internet of Things, including a communication chip, a fourth inductor, a second antenna mounting base, and a first antenna; one antenna port of the communication chip is connected to the fourth inductor, and the fourth inductor is connected to both the second antenna mounting base and the first antenna; a third contact is provided at one end of the fourth inductor.

[0006] Preferably, the first antenna is a printed antenna or an antenna pre-mounted on a circuit board; the second antenna mount is mounted on the circuit board.

[0007] The second antenna mounting bracket includes an antenna end and at least one grounding end GND; the antenna end is connected to a fourth inductor.

[0008] The second antenna is detachably mounted on the second antenna mount.

[0009] Preferably, the detection end of the external detection device is connected to the third contact and ground.

[0010] Preferably, one end of the ninth capacitor is connected to one end of the fourth inductor; the other end of the ninth capacitor is grounded; one end of the twenty-sixth capacitor is connected to one end of the fourth inductor; the other end of the twenty-sixth capacitor is grounded.

[0011] A fifth inductor is provided between the fourth inductor and the first antenna, and one end of the fifth inductor is grounded through the twenty-seventh capacitor;

[0012] The antenna end of the second antenna mount is connected to the third contact via the ninth resistor;

[0013] The fourth inductor is connected to the antenna port through the third inductor, and the third inductor is grounded through the seventh capacitor.

[0014] Preferably, the present invention further includes a pin header connected to an external circuit and at least one transceiver; the transceiver includes a first transceiver;

[0015] The header P1 includes interfaces X1F and X1C, which are respectively connected to the first input power supply and the second input power supply;

[0016] The X1C interface is connected to one end of the first plug via a filter and a 22nd capacitor; the other end of the first plug is connected to the VCCA terminal of the second transceiver.

[0017] The X1F interface connects to the VCCA terminal;

[0018] The two ends of the second plug are connected to the VCCA and VCCB terminals of the second transceiver, respectively.

[0019] Preferably, the second input power supply provides power while the first input power supply does not. The two ends of the first plug are connected, and the two ends of the second plug are disconnected. The second input power supply provides power to the VCCA terminal of the second transceiver. The second input power supply provides power to the VCCB terminal through the power chip.

[0020] The second input power supply is not supplying power, while the first input power supply is supplying power. Disconnect both ends of the first plug and connect both ends of the second plug. The first input power supply supplies power to the VCCA and VCCB terminals of the second transceiver. The first input power supply is used as the power supply.

[0021] Preferably, the first input power supply is connected to the X1D interface of the pin header through a second resistor; the X1D interface is connected to the serial port transmit pin of an external circuit.

[0022] The X1D interface is also connected to port B of the first transceiver; port A of the first transceiver is connected to port PC2 of the communication chip.

[0023] Preferably, one end of the X1E interface of the pin header is connected to an external serial port receiving pin, and the other end is connected to the A port of the second transceiver; the B port of the second transceiver is connected to the PC1 port of the communication chip.

[0024] Compared with the prior art, the beneficial effects of this utility model are as follows: impedance matching of the antenna is achieved through a fourth inductor; a second antenna mounting bracket is reserved on the circuit so that a second antenna can be connected externally when the first antenna cannot be adapted or meet the installation requirements; the antenna in use can be tested by connecting the detection terminal of an external testing device to the third contact and ground; diverse installation requirements of the antenna are met at a lower cost, improving the applicability of short-range communication circuits and their circuit boards; and antenna performance is conveniently tested. Attached Figure Description

[0025] Figure 1 This is a circuit diagram of the communication chip for the short-range communication circuit of this utility model;

[0026] Figure 2 This is a bus transceiver circuit diagram;

[0027] Figure 3 This is the circuit diagram of the power supply chip.

[0028] In the diagram, the following capacitors are marked: Zig, communication chip; C4, fourth capacitor; C5, fifth capacitor; C6, sixth capacitor; C7, seventh capacitor; C9, ninth capacitor; C10, tenth capacitor; C11, eleventh capacitor; C12, twelfth capacitor; C13, thirteenth capacitor; C14, fourteenth capacitor; C16, sixteenth capacitor; C17, seventeenth capacitor; C18, eighteenth capacitor; C19, nineteenth capacitor.

[0029] C21, capacitor number 21; C22, capacitor number 22; C23, capacitor number 23; C25, capacitor number 25;

[0030] C26, the twenty-sixth resistor; C27, the twenty-seventh resistor;

[0031] ANT, antenna; E1, first antenna; E2, second antenna mounting bracket;

[0032] L2, second inductor; L3, third inductor; L4, fourth inductor; L5, fifth inductor; L6, sixth inductor; L8, eighth inductor;

[0033] R2, the second resistor; R3, the third resistor; R6, the sixth resistor; R7, the seventh resistor; R8, the eighth resistor; R9, the ninth resistor;

[0034] VDD3.3, power supply; VEXT, first input power supply; V5V, second input power supply;

[0035] TxD, transmit pin; RxD, receive pin;

[0036] TN1, filter; BUF, transceiver; D1, first transceiver; D2, second transceiver; D3, power supply chip;

[0037] V1, first diode; V2, second diode;

[0038] P1, pin header; J1, first plug; J2, second plug; J3, third contact. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0040] The present invention will now be described in further detail with reference to the accompanying drawings:

[0041] This utility model provides a short-range communication circuit based on the Internet of Things, such as... Figure 1 As shown, it includes a communication chip Zig, a fourth inductor L4, a second antenna mounting bracket E2, and a first antenna E1; one antenna port RF2G4_IO2 of the communication chip Zig is connected to the fourth inductor L4, and the fourth inductor L4 is connected to the second antenna mounting bracket E2 and the first antenna E1 respectively; a third contact J3 is provided at one end of the fourth inductor L4.

[0042] The antenna ANT is impedance matched by the fourth inductor L4; a second antenna mounting bracket E2 is reserved on the circuit so that the second antenna can be connected externally when the first antenna E1 cannot be adapted or meet the installation requirements; the antenna ANT in use can be tested by connecting the detection terminal of an external testing device to the third contact J3 and ground GND; the diverse installation requirements of the antenna ANT are met at a lower cost, improving the applicability of short-range communication circuits and their circuit boards; and the antenna performance is easily tested.

[0043] The first antenna E1 is a printed antenna or an antenna pre-mounted on a circuit board; the second antenna mount E2 is mounted on the circuit board. The second antenna mount E2 includes an antenna terminal ant and at least one ground terminal GND; the antenna terminal ant is connected to a fourth inductor L4. The external second antenna is detachably mounted on the second antenna mount E2.

[0044] Specifically, this utility model also includes a ninth capacitor C9 and a twenty-sixth capacitor C26; one end of the ninth capacitor C9 is connected to one end of the fourth inductor L4; the other end of the ninth capacitor C9 is grounded for impedance matching; one end of the twenty-sixth capacitor C26 is connected to the other end of the fourth inductor L4; the other end of the twenty-sixth capacitor C26 is grounded. That is, the two ends of the fourth inductor L4 are grounded through the ninth capacitor C9 and the twenty-sixth capacitor C26 respectively.

[0045] A fifth inductor L5 is provided between the fourth inductor L4 and the first antenna E1. One end of the fifth inductor L5 is grounded through the twenty-seventh capacitor C27. The antenna end ant of the second antenna mounting bracket E2 is connected to the third contact J3 through the ninth resistor.

[0046] One end of the fourth inductor L4 is also provided with a third inductor L3, which is grounded through the seventh capacitor C7.

[0047] In one specific embodiment, the communication chip model used is EFR32MG21, but it is not limited to this; other communication chips such as TLSR8258F512ET32 can also be used. These communication chips have at least one antenna port.

[0048] Among them, the power supply VDD3.3 is connected to the reset terminal RESET of the communication chip Zig through the third resistor R3, and the reset terminal RESET is grounded through the fourth capacitor C4.

[0049] The power supply VDD3.3 is connected to the antenna power supply terminal RFVDD through the second inductor L2. The antenna power supply terminal RFVDD is grounded through the fifth capacitor C5 and the sixth capacitor C6.

[0050] The power supply VDD3.3 is connected to the PAVDD terminal of the communication chip Zig through the sixth inductor L6. The PAVDD terminal is grounded through the tenth capacitor C10 and the eleventh capacitor C11, respectively.

[0051] The PB1 terminal of the communication chip Zig is grounded through the seventh resistor R7 and the second diode V2; the PB0 terminal is grounded through the eighth resistor R8 and the first diode V1.

[0052] The DECOUPLE terminal of the communication chip Zig is grounded through the sixteenth capacitor C16.

[0053] The DVDD terminal of the communication chip Zig is connected to the power supply VDD3.3; the DVDD terminal is grounded through the fourteenth capacitor C14 and the nineteenth capacitor C19.

[0054] The AVDD terminal of the communication chip Zig is connected to the power supply VDD3.3 through the eighth inductor L8 and the sixth resistor R6; the AVDD terminal is grounded through the thirteenth capacitor C13 and the eighteenth capacitor C18.

[0055] The IOVDD terminal of the communication chip Zig is connected to the power supply VDD3.3, and the IOVDD terminal is grounded through the twelfth capacitor C12 and the seventeenth capacitor C17.

[0056] The power supply VDD3.3 operates at 3.3V and can be supplied externally. Alternatively, a power supply module can be integrated into the circuit to provide VDD3.3.

[0057] Figure 2 The circuitry for bus transceiver in a short-range communication circuit is shown, including a header P1 connected to an external circuit and at least one transceiver BUF, such as connected to an external gateway or the main circuit board of an electronic device via header P. The transceiver BUF includes a first transceiver D1 and a second transceiver D2, and may be of the model 74LVC1T45DCK-SC70, but is not limited to this.

[0058] The header P1 includes interfaces X1F and X1C for the first input power supply VEXT and the second input power supply V5V; the external circuit supplies either the first input power supply VEXT or the second input power supply V5V, with the first input power supply VEXT being 3.3V and the second input power supply V5V being 5V.

[0059] The X1C connector of pin header P1 is connected to one end of the first connector J1 via filter TN1 and the 22nd capacitor C22; the other end of the first connector J1 is connected to the VCCA terminal of the second transceiver D2; the X1F connector is connected to the VCCA terminal. For example... Figure 3 The X1C interface connects to the input terminal of power chip D3, which outputs power supply VDD3.3. The two ends of the second connector J2 connect to the VCCA and VCCB terminals of the second transceiver D2, respectively. The VCCB terminal is connected to the power supply VDD3.3.

[0060] When the second input power supply V5V is powered and the first input power supply VEXT is not powered, connect the two ends of the first plug J1 and disconnect the two ends of the second plug J2. The second input power supply V5V powers the VCCA terminal of the second transceiver D2; the second input power supply V5V powers the VCCB terminal through the power chip D3.

[0061] When the second input power supply V5V is not supplying power and the first input power supply VEXT is supplying power, disconnect both ends of the first plug J1 and connect both ends of the second plug J2. The first input power supply VEXT supplies power to the VCCA and VCCB terminals of the second transceiver D2 and supplies power to the power supply VDD3.3. At this time, the power chip D3 has no input power and is not working.

[0062] By simply modifying the first plug J1 and the second plug J2, it can accommodate both 5V and 3.3V input power supplies, improving adaptability and avoiding the need to develop an entire communication circuit separately for different input voltages; thus reducing mold opening costs.

[0063] More specifically, the X1C terminal is grounded through the twenty-first capacitor C21. The twenty-second capacitor C22 is a four-port capacitor, with two ports grounded. The X1F terminal is grounded through the twenty-third capacitor C23. The output of the power chip D3 is grounded through multiple parallel twenty-fifth capacitors C25.

[0064] The first input power supply VEXT is connected to the X1D interface of the header P1 through the second resistor R2, which is connected to the serial port transmit pin TxD of the external circuit; the X1D interface is connected to the B port of the first transceiver D1; the A port of the first transceiver D1 is connected to the PC2 port of the communication chip Zig.

[0065] One end of the X1E interface of pin header P1 is connected to the external serial port receive pin RxD, and the other end is connected to port A of the second transceiver D2; port B of the second transceiver D2 is connected to port PC1 of the communication chip Zig. This enables serial port connection of the communication chip Zig.

[0066] In this invention, the dual-antenna layout improves the applicability of short-range communication circuits at a low cost. The second antenna mounting bracket E2 can accommodate different types of antennas to suit the power requirements of the installation scenario. When installing the antenna on the second antenna mounting bracket E2, the first antenna E1 can be disconnected by removing the fifth inductor L5. This invention provides impedance matching for the antenna ANT through the combination of capacitors and inductors; it also provides impedance matching for each power port of the communication port.

[0067] This invention also adapts to a 5V second input power supply V5V by cooperating with a bus transceiver circuit and a power chip circuit, and adapts to a 3.3V first input power supply VEXT by simply modifying the connection state of the first plug J1 and the second plug J2, thereby improving applicability and reducing mold opening costs.

[0068] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A short-range communication circuit based on the Internet of Things, characterized in that It includes a communication chip, a fourth inductor, a second antenna mounting base, and a first antenna; An antenna port of the communication chip is connected to the fourth inductor, and the fourth inductor is respectively connected to the second antenna mounting base and the first antenna; a third contact is provided at one end of the fourth inductor.

2. The short-range communication circuit according to claim 1, wherein The first antenna is a printed antenna or an antenna pre-installed on a circuit board; the second antenna mounting base is installed on the circuit board; The second antenna mounting base includes an antenna end and at least one ground end; the antenna end is connected to the fourth inductor; The second antenna is detachably installed on the second antenna mounting base.

3. The short-range communication circuit according to claim 1, wherein The detection end of the external detection device is connected to the third contact and the ground.

4. The short-range communication circuit according to claim 1, wherein One end of a ninth capacitor is connected to one end of the fourth inductor; the other end of the ninth capacitor is grounded; one end of a twenty-sixth capacitor is connected to one end of the fourth inductor; the other end of the twenty-sixth capacitor is grounded; A fifth inductor is provided between the fourth inductor and the first antenna, and one end of the fifth inductor is grounded through a twenty-seventh capacitor; The antenna end of the second antenna mounting base is connected to the third contact through a ninth resistor; The fourth inductor is connected to the antenna port through a third inductor, and the third inductor is grounded through a seventh capacitor.

5. The short-range communication circuit according to claim 1, wherein It also includes a pin header connected to an external circuit and at least one transceiver; the transceiver includes a first transceiver; The pin header includes an X1 F interface and an X1 C interface respectively connected to a first input power supply and a second input power supply; The X1 C interface is connected to one end of a first plug through a filter and a twenty-second capacitor; the other end of the first plug is connected to the VCCA terminal of the second transceiver; The X1 F interface of the pin header is connected to the VCCA terminal; Both ends of a second plug are respectively connected to the VCCA terminal and the VCCB terminal of the second transceiver.

6. The short-range communication circuit according to claim 5, wherein When the second input power supply supplies power and the first input power supply does not supply power, connect both ends of the first plug and disconnect both ends of the second plug, and the second input power supply supplies power to the VCCA terminal of the second transceiver; the second input power supply supplies power to the VCCB terminal through a power chip.

7. The short-range communication circuit according to claim 5, wherein When the second input power supply does not supply power and the first input power supply supplies power, disconnect both ends of the first plug and connect both ends of the second plug, and the first input power supply supplies power to the VCCA terminal and the VCCB terminal of the second transceiver, and the first input power supply serves as the power supply.

8. The short-range communication circuit according to claim 5, wherein The first input power supply is connected to the X1 D interface of the pin header through a second resistor; the X1 D interface is connected to the serial port transmit pin of the external circuit; The X1 D interface is also connected to the B port of the first transceiver; the A port of the first transceiver is connected to the PC2 port of the communication chip.

9. The short-range communication circuit according to claim 8, wherein One end of the X1 E interface of the pin header is connected to the external serial port receive pin, and the other end is connected to the A port of the second transceiver; the B port of the second transceiver is connected to the PC1 port of the communication chip.

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