Communication transmission circuit, system and electronic equipment

Abstract

The utility model relates to a communication transmission circuit and system and electronic equipment, and the circuit comprises a first conversion module and a second conversion module, the first conversion module comprises a low-level input end and a high-level output end, and the second conversion module comprises a high-level input end and a low-level output end; the low-level input end is connected with a host signal output end, the high-level output end is connected with the high-level input end, and the low-level output end is connected with a slave signal input end. According to the communication transmission circuit provided by the invention, the conversion from the low-level signal to the high-level signal of the host signal is realized through the first conversion module, the conversion from the high-level signal to the low-level signal is realized through the second conversion module, and the circuit is formed by low-cost elements; therefore, the communication transmission process between the medical devices is not affected by the level output voltage of the processor, and long-distance transmission is stably realized.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a communication transmission circuit, system and electronic equipment. Background Art

[0002] The application components of medical equipment usually use the I2C communication protocol to communicate with the host, and the host's MCU generally supports TTL3.3V level output. Due to the limitation of the level amplitude, when the transmission line is long and the line loss is aggravated, the level of the signal sent by the host reaches the slave or the signal from the slave reaches the host. When it drops a lot, it causes data recognition errors.

[0003] Traditionally, dedicated chips such as relay chips or interface chips are used to implement interface conversion to achieve long-distance transmission. However, dedicated chips have the problems of high cost and poor interchangeability. Utility Model Content

[0004] In order to solve the above technical problems, it is necessary to provide a communication transmission circuit, system and electronic equipment that can effectively reduce costs and can be flexibly applied. The specific solution is as follows:

[0005] In a first aspect, this embodiment provides a communication transmission circuit, including:

[0006] A first conversion module and a second conversion module, wherein the first conversion module includes a low level input terminal and a high level output terminal, and the second conversion module includes a high level input terminal and a low level output terminal;

[0007] The low level input terminal is connected to the host signal output terminal, the high level output terminal is connected to the high level input terminal, and the low level output terminal is connected to the slave signal input terminal.

[0008] In one embodiment, the first conversion module includes a first switch unit, a first current limiting unit, a first pull-up unit, a second current limiting unit, and a second pull-up unit;

[0009] The first end and the second end of the first switch unit are both pulled up to a first voltage via the first pull-up unit;

[0010] The second end of the first switch unit is also connected to the host signal output end via the first current limiting unit; the third end of the first switch unit is pulled up to a second voltage via the second pull-up unit;

[0011] The third terminal of the first switch unit is connected to the high level input terminal via the second current limiting unit.

[0012] In one embodiment, the second conversion module includes a second switch unit, a third current limiting unit, a third pull-up unit, a fourth current limiting unit and a fourth pull-up unit;

[0013] The first end and the second end of the second switch unit are both pulled up to a third voltage via the third pull-up unit;

[0014] The second end of the second switch unit is also connected to the slave signal input end via the third current limiting unit; the third end of the second switch unit is pulled up to a fourth voltage via the fourth pull-up unit;

[0015] The third terminal of the second switch unit is connected to the high level output terminal via the fourth current limiting unit.

[0016] In one embodiment, the first switch unit includes a first transistor, the second switch unit includes a second transistor, the first pull-up unit includes a first resistor and a second resistor, and the third pull-up unit includes a third resistor and a fourth resistor;

[0017] wherein the first end of the first transistor is pulled up to a first voltage via the first resistor, and the second end of the first transistor is pulled up to a first voltage via the second resistor;

[0018] The first terminal of the second transistor is pulled up to a third voltage via the third resistor, and the second terminal of the second transistor is pulled up to a third voltage via the fourth resistor.

[0019] In one embodiment, the first voltage is equal to the third voltage, and the second voltage is equal to the fourth voltage.

[0020] In one embodiment, it also includes:

[0021] An electrostatic protection module is connected to the low level input terminal, the high level output terminal, the high level input terminal and the low level output terminal respectively.

[0022] In one embodiment, the electrostatic protection module includes a first diode, a second diode, a third diode, and a fourth diode;

[0023] One end of the first diode is connected to the low level input end, and the other end of the first diode is grounded;

[0024] One end of the second diode is connected to the high level output end, and the other end of the second diode is grounded;

[0025] One end of the third diode is connected to the high level input end, and the other end of the third diode is grounded;

[0026] One end of the fourth diode is connected to the low level output end, and the other end of the fourth diode is grounded.

[0027] In one embodiment, the first diode, the second diode, the third diode and the fourth diode are all electrostatic protection diodes.

[0028] In a second aspect, this embodiment provides a communication transmission system, including a host, a slave, and the communication transmission circuit described in the first aspect, wherein the host is communicatively connected with the slave via the communication transmission circuit.

[0029] In a third aspect, this embodiment provides an electronic device, including the communication system described in the first aspect.

[0030] In summary, the present application provides a communication transmission circuit, system and electronic device, including: a first conversion module and a second conversion module, wherein the first conversion module includes a low-level input terminal and a high-level output terminal, and the second conversion module includes a high-level input terminal and a low-level output terminal; the low-level input terminal is connected to the host signal output terminal, the high-level output terminal is connected to the high-level input terminal, and the low-level output terminal is connected to the slave signal input terminal. The communication transmission circuit provided by the present application realizes the conversion of the low-level signal of the host signal to the high-level signal through the first conversion module, and then realizes the conversion of the high-level signal to the low-level signal through the second conversion module. The circuit composed of low-cost components makes the communication transmission process between medical devices not affected by the processor level output voltage, and stably realizes long-distance transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0032] Figure 1 is a schematic diagram of a module structure of a communication transmission circuit in an embodiment;

[0033] Figure 2 is a schematic diagram of a module structure of a communication transmission circuit in another embodiment;

[0034] Figure 3 is a circuit diagram of a communication transmission circuit in an embodiment;

[0035] Figure 4 is a schematic diagram of a module structure of a communication transmission circuit in yet another embodiment;

[0036] Figure 5 It is a circuit diagram of a communication transmission circuit in another embodiment.

[0037] Description of reference numerals:

[0038] Communication transmission circuit-100A; communication transmission circuit-100B; first conversion module-110; first switch unit-111; first current limiting unit-112; first pull-up unit-113; second current limiting unit-114; second pull-up unit-115; second conversion module-120; third current limiting unit-121; third pull-up unit-123; fourth current limiting unit-124; fourth pull-up unit-125; host-200; slave-300. DETAILED DESCRIPTION

[0039] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0041] It is understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0042] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if the connected circuits, modules, units, etc. have electrical signals or data transmission between each other.

[0043] It can be understood that “at least one” means one or more, “plurality” means two or more, and “at least part of an element” means part or all of an element.

[0044] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the relevant listed items.

[0045] like Figure 1 As shown, this embodiment provides a communication transmission circuit, including: a first conversion module 110 and a second conversion module 120. Among them, the host 200 is connected to the slave 300 through the first conversion module 110 and the second conversion module 120 in turn. When the host 200 sends a communication signal to the slave 300, the first conversion module 110 can be used to convert the communication signal output by the host 200 into a high-level signal with a higher voltage, and transmit it through a cable between the first conversion module 110 and the second conversion module 120. The second conversion module 120 can convert the high-level signal transmitted on the cable into a low-level signal corresponding to the voltage value of the communication signal that can be received by the slave 300, so that the slave 300 can receive the communication signal sent by the host 200.

[0046] In a specific embodiment, the first conversion module 110 includes a low level input terminal and a high level output terminal, and the second conversion module 120 includes a high level input terminal and a low level output terminal. When the host 200 sends a communication signal to the slave 300, the low level input terminal of the first conversion module 110 is connected to the host signal output terminal of the host 200, the high level output terminal of the first conversion module 110 is connected to the high level input terminal of the second conversion module 120, and the low level output terminal of the second conversion module 120 is connected to the slave signal input terminal of the slave 300.

[0047] In one embodiment, the structures of the first conversion module 110 and the second conversion module 120 are symmetrical structures. When the slave 300 sends a communication signal to the host 200, the second conversion module 120 can be used to convert the communication signal output by the slave 300 into a high-level signal with a higher voltage, and transmit it through the cable between the second conversion module 120 and the first conversion module 110. The first conversion module 110 can convert the high-level signal transmitted on the cable into a low-level signal corresponding to the voltage value of the communication signal that matches the host 200, so that the host 200 can receive the communication signal sent by the slave 300.

[0048] In a specific embodiment, the first conversion module 110 may include a low level output terminal and a high level input terminal, and the second conversion module 120 includes a high level output terminal and a low level input terminal. When the slave 300 sends a communication signal to the host 200, the low level input terminal of the second conversion module 120 is connected to the slave signal output terminal of the slave 300, the high level output terminal of the second conversion module 120 is connected to the high level input terminal of the first conversion module 110, and the low level output terminal of the first conversion module 110 is connected to the host signal input terminal of the host 200.

[0049] It should be noted that when the host 200 sends a communication signal to the slave 300, the first conversion module 110 can be used to convert the low-level signal into a high-level signal, so that the communication signal is stably transmitted in the cable between the first conversion module 110 and the second conversion module 120 in the form of a high-level signal, without worrying about the voltage loss caused by the cable length. The second conversion module 120 can convert the high-level signal in the cable into a low-level signal, so that the slave 300 can safely receive the communication signal.

[0050] When the slave 300 sends a communication signal to the host 200, the second conversion module 120 can be used to convert the low-level signal into a high-level signal, so that the communication signal is stably transmitted in a high-level manner in the cable between the second conversion module 120 and the first conversion module 110. The first conversion module 110 can convert the high-level signal in the cable into a low-level signal, so that the host 200 can safely receive the communication signal.

[0051] It should be noted that the high-level signal of the cable in this embodiment is a signal greater than or equal to a preset voltage threshold, for example, the high-level signal is a level signal greater than or equal to 12 V. It should be noted that this embodiment does not limit the specific value of the high-level signal, but should ensure that the high-level signal transmitted on the cable between the first conversion module and the second conversion module will not be affected by line loss, resulting in loss of communication information.

[0052] The low-level signal of the cable in this embodiment is a signal less than or equal to a preset voltage threshold, for example, the low-level signal is a level signal less than or equal to 3.3 V. It should be noted that this embodiment also does not limit the specific value of the low-level signal, and can be determined according to the voltage value of the communication signal that can be received by the host or slave in the actual application scenario.

[0053] In addition, the first conversion module and the second conversion module in the present embodiment together constitute a communication transmission circuit, which is only used to connect two interfaces corresponding to one type of the host and the slave. For example, for a host and a slave that use the I2C (Inter-Integrated Circuit) communication protocol for data communication, a serial clock line (Serial Clock Line, referred to as SCL) interface and a serial data line (Serial Data Line, referred to as SDA) interface are generally included. The SDA interface of the host can be connected to the SDA interface of the slave through a communication transmission circuit. The SCL interface of the host can be connected to the SCL interface of the slave through another communication transmission circuit.

[0054] In summary, this embodiment provides a communication transmission circuit. When long-distance communication signal transmission is performed between a host and a slave, the transmitting end of the host or the slave can convert the low-level signal sent by the host or the slave into a high-level signal through the first conversion module or the second conversion module, so that during the communication signal transmission process, the communication signal is always transmitted with a high-level signal, which can effectively overcome the long-distance transmission problem of long transmission lines and large line losses. The receiving end of the host or the slave converts the high-level signal into a low-level signal through the second conversion module or the first conversion module, so that the communication signal transmitted to the slave or the host meets the safety requirements and ensures the equipment safety of the host and the slave.

[0055] In one embodiment, if Figure 2 As shown, the first conversion module 110 includes a first switch unit 111 , a first current limiting unit 112 , a first pull-up unit 113 , a second current limiting unit 114 and a second pull-up unit 115 .

[0056] Specifically, the first switch unit 111 includes a first end, a second end and a third end, wherein the first end is a control end of the first switch unit 111 , the second end is a receiving end of the first switch unit 111 , and the third end is a sending end of the first switch unit 111 .

[0057] In a specific embodiment, the second end of the first switch unit 111 is connected to the host signal output end via the first current limiting unit 112 , and the third end of the first switch unit 111 is connected to the high level input end via the second current limiting unit 114 .

[0058] The first current limiting unit 112 and the second current limiting unit 114 can effectively include the second end and the third end of the first switch unit 111 to prevent the current output from the host signal output end or the current at the high level input end from damaging the first switch unit 111. Specifically, Figure 3 As shown, the first current limiting unit 112 may include a current limiting resistor R29, and the second current limiting unit 114 may include a current limiting resistor R6.

[0059] In a specific application process, when the host sends a communication signal to the slave, the first end and the second end of the first switch unit 111 are both pulled up to the first voltage via the first pull-up unit 113. At this time, if the communication signal sent by the host is a high-level signal, such as a 3.3V signal, the first switch unit 111 is cut off. The third end of the first switch unit 111 is pulled up to the second voltage via the second pull-up unit 115. When the first switch unit 111 is cut off, the output voltage of the third end of the first switch unit 111 is the second voltage. It should be noted that the first voltage is usually a voltage that matches the voltage value of the communication signal sent by the host or the slave, such as 3.3V, and the second voltage is a voltage of a high-level signal voltage value that enables the communication signal on the cable to be stably transmitted, such as 12V.

[0060] If the communication signal sent by the host is a low-level signal, for example 0V, the first switch unit 111 is turned on. At this time, the third end of the first switch unit 111 will not be pulled up to the second voltage by the second pull-up unit 115. When the first switch unit 111 is turned on, the output voltage of the third end of the first switch unit 111 is the voltage of the communication signal sent by the host, that is, 0V.

[0061] In one embodiment, if Figure 2 As shown, the second conversion module 120 includes a second switch unit 121 , a third current limiting unit 122 , a third pull-up unit 123 , a fourth current limiting unit 124 and a fourth pull-up unit 125 .

[0062] Specifically, the second switch unit 121 includes a first end, a second end and a third end, wherein the first end is a control end of the second switch unit 121 , the second end is a receiving end of the second switch unit 121 , and the third end is an output end of the second switch unit 121 .

[0063] In a specific embodiment, the second end of the second switch unit 121 is also connected to the slave signal input end via the third current limiting unit 122 , and the third end of the second switch unit 121 is connected to the high level output end via the fourth current limiting unit 124 .

[0064] The third current limiting unit 122 and the fourth current limiting unit 124 can effectively limit the current at the second end and the third end of the second switch unit 121, thereby effectively protecting the second switch unit 121 and preventing the second switch unit 121 from being damaged due to overcurrent abnormality. Figure 3 As shown, the third current limiting unit 122 may include a current limiting resistor R8, and the fourth current limiting unit 124 may include a current limiting resistor R7.

[0065] In a specific application process, when the level signal output by the high-level output terminal is a high-level signal, that is, a 12V level signal, the third end of the second switch unit 121 is pulled up to the fourth voltage via the fourth pull-up unit 125, and the second switch unit 121 is turned off. When the second switch unit 121 is in the off state, the first end and the second end of the second switch unit 121 are both pulled up to the third voltage via the third pull-up unit 123, and the voltage received by the slave signal input terminal is the third voltage. It should be noted that the third voltage is usually a voltage that matches the voltage value of the communication signal sent by the host or the slave, such as 3.3V, and the fourth voltage is a voltage of a high-level signal voltage value that enables the communication signal on the cable to be stably transmitted, such as 12V.

[0066] When the level signal outputted by the high level output terminal is a low level signal, i.e., a 0V level signal, the second switch unit 121 is turned on. When the second switch unit 121 is turned on, the output voltage of the second end of the second switch unit 121 is also pulled down to a 0V level signal, and the voltage received by the slave signal input terminal is a low level signal.

[0067] In summary, this embodiment can effectively cooperate with the transmission mode of the communication signal as an open-drain signal under the I2C communication protocol through the level conversion effect of the first conversion unit and the second conversion unit. When the host sends a communication signal (3.3V), the first conversion unit realizes the conversion of the low-level signal (3.3V) to a high-level signal (12V), and the second conversion unit realizes the conversion of the high-level signal (12V) to a low-level signal (3.3V), and the slave receives the communication signal (3.3V). When the host sends a communication signal (0V), the first conversion unit and the second conversion unit both convert the level signal to 0V, and the slave receives the communication signal (0V). The first conversion unit and the second conversion unit can effectively realize the switching of the level signal from high to low and from low to high.

[0068] In one embodiment, if Figure 3 As shown, the first switch unit 111 includes a first transistor, the second switch unit 121 includes a second transistor, the first pull-up unit 113 includes a first resistor and a second resistor, and the third pull-up unit 123 includes a third resistor and a fourth resistor. The first transistor may be a transistor Q1, the second transistor may be a transistor Q2, the first resistor is a resistor R1, the second resistor is a resistor R31, the third resistor is a resistor R2, and the fourth resistor is a resistor R3.

[0069] Among them, the first end of the first transistor is pulled up to the first voltage via the first resistor, the second end of the first transistor is pulled up to the first voltage via the second resistor, the first end of the second transistor is pulled up to the third voltage via the third resistor, and the second end of the second transistor is pulled up to the third voltage via the fourth resistor.

[0070] In a specific embodiment, the first transistor and the second transistor may both be NMOS transistors. The first transistor and the second transistor may also be adaptively replaced with PMOS transistors or triodes according to the needs of actual application scenarios.

[0071] When the first transistor and the second transistor are both NMOS transistors, the first end is a gate, the second end is a source, and the third end is a drain.

[0072] In actual application, the gate of transistor Q1 is pulled up to the first voltage, i.e. 3.3V, via resistor R1, the source of transistor Q1 is pulled up to the first voltage, i.e. 3.3V, via resistor R31, the gate of transistor Q2 is pulled up to the third voltage, i.e. 3.3V, via resistor R2, and the source of transistor Q2 is pulled up to the third voltage, i.e. 3.3V, via resistor R3.

[0073] Need to know, such as Figure 3 As shown, transistor Q1 and transistor Q2 are arranged opposite to each other, and the drain of transistor Q1 is connected to the drain of transistor Q2 via resistor R6 and resistor R7. Transistor Q1 and transistor Q2 are of symmetrical structural design, so that the host can send a communication signal to the slave through the communication transmission circuit provided by this embodiment, and the slave can also send a communication signal to the host through the communication transmission circuit provided by this embodiment, and bidirectional long-distance communication between the host and the slave is realized based on the communication transmission circuit provided by this embodiment.

[0074] In one embodiment, the first voltage is equal to the third voltage, and the second voltage is equal to the fourth voltage.

[0075] Specifically, Figure 3 As shown, the first voltage and the third voltage may be voltage values ​​provided by a 3.3V voltage source, and the second voltage and the fourth voltage may be voltages provided by a 12V voltage source. In actual application scenarios, the voltage values ​​of the first voltage and the third voltage, as well as the voltage values ​​of the second voltage and the fourth voltage, may be adaptively configured according to the needs of the actual application scenarios, and this embodiment does not make a sole limitation on this.

[0076] In one embodiment, the communication transmission circuit further includes:

[0077] The electrostatic protection module is respectively connected to the low level input terminal, the high level output terminal, the high level input terminal and the low level output terminal.

[0078] In a specific embodiment, the electrostatic protection module is mainly used to prevent static electricity from causing signal communication failures in the communication transmission circuit.

[0079] In one embodiment, if Figure 3As shown, the electrostatic protection module includes a first diode, a second diode, a third diode, and a fourth diode, wherein the first diode may be a diode D1, the second diode may be a diode Q2, the third diode may be a diode Q3, and the fourth diode may be a diode Q4.

[0080] One end of the first diode is connected to the low level input terminal, and the other end of the first diode is grounded; one end of the second diode is connected to the high level output terminal, and the other end of the second diode is grounded; one end of the third diode is connected to the high level input terminal, and the other end of the third diode is grounded; one end of the fourth diode is connected to the low level output terminal, and the other end of the fourth diode is grounded.

[0081] Specifically, Figure 3 As shown, diode D1 is connected to the host signal output terminal Master-SDA_3.3V, diode D2 is connected to the high level output terminal SDA_12V and one end of resistor R6, diode D3 is connected to the high level input terminal SDA_12V and one end of resistor R7, and diode D4 is connected to the slave signal input terminal Slave-SDA_3.3V.

[0082] In a specific embodiment, the first diode, the second diode, the third diode and the fourth diode are all electrostatic protection diodes.

[0083] It is understandable that the electrostatic protection module may also be in other forms, not limited to the forms mentioned in the above embodiments, as long as it can achieve the function of protecting the circuit from the influence of static electricity.

[0084] In summary, this embodiment provides a communication transmission circuit, which can form a level conversion circuit through low-cost electronic components, and is used for long-distance communication transmission between the host and the slave, ensuring data security during communication between the host and the slave, and avoiding data loss due to level loss. In addition, this embodiment does not need to be configured with a special electronic chip, and only realizes level conversion through electronic components, and realizes communication signals through hardware circuits, which effectively reduces the composition cost of the communication circuit and allows for more flexible circuit configuration.

[0085] In a more detailed embodiment, Figure 4 and Figure 5 As shown, the communication transmission circuit in this embodiment can be applied between a host and a slave that communicate based on the I2C communication protocol, wherein two data transmission paths of the I2C communication protocol are connected through corresponding communication transmission circuits.

[0086] Among them, the SDA interface of the host is connected to the SDA interface of the slave through the communication transmission circuit 100A, and the SCL interface of the host is connected to the SCL interface of the slave through the communication transmission circuit 100B. In the specific implementation process, when the host Master-SDA_3.3V sends an SDA signal, it reaches the source of the transistor Q1 through the current limiting resistor R29, and the resistor R31 is the pull-up resistor of the source of the transistor Q1, and the source of the transistor Q1 is pulled up to 3.3V. Since the SDA signal sent by the host under the I2C communication protocol is an open-drain signal, the gate of the transistor Q1 is pulled up to 3.3V through the resistor R1, the current limiting resistor R6 is the output current limiting resistor of the drain of the transistor Q1, and R4 is the pull-up resistor of the drain.

[0087] When the communication signal output by Master-SDA_3.3V is at a high level, VGS of transistor Q1 is 0, transistor Q1 is turned off, and the high level output terminal SDA_12V of transistor Q1 is pulled up to a high level of 12V through resistor R4.

[0088] When the communication signal output by Master-SDA_3.3V is at a low level, the transistor Q1 is turned on, and since the resistor R4>>resistor R29, the drain of the transistor Q1 is pulled to a low level, thereby realizing the level conversion of the output end of the first conversion module.

[0089] When the level signal is transmitted through the cable to the second conversion module connected to the slave end, it reaches the drain of the transistor Q2 through the current limiting resistor R7, and the resistor R5 is the pull-up resistor of the drain of the transistor Q2. The gate of the transistor Q2 is pulled up to 3.3V through the resistor R2. The resistor R8 is the output current limiting resistor of the source of the transistor Q2, and the source of the transistor Q2 is pulled up to 3.3V through the resistor R3.

[0090] When the output terminal SDA_12V of the first conversion module outputs a high-level signal, the transistor Q2 is in the cut-off state, and the pull-up resistor R3 pulls up the source voltage of the transistor Q2 to 3.3V, and then reaches the slave signal input terminal Slave-SDA_3.3V of the slave through the current limiting resistor R8, thereby pulling up the level signal of the slave signal input terminal Slave-SDA_3.3V of the slave.

[0091] When the output terminal SDA_12V of the first conversion module outputs a low level, the transistor Q2 pulls down the level of the drain of the transistor Q2 through the body diode conduction state, thereby pulling down the level signal of the slave signal input terminal Slave-SDA_3.3V of the slave, completing the conversion of the level of the slave receiving end from high to low.

[0092] In a specific embodiment, the level conversion principles of the SDA and SCL ends of the host are the same, the structures of the communication transmission circuit 100A and the communication transmission circuit 100B are also the same, and the specific implementation process of the communication transmission circuit 100B can refer to the specific implementation process of the aforementioned communication transmission circuit 100A, which will not be repeated here.

[0093] It should be noted that this embodiment is described according to the connection relationship between the host and the slave to send a communication signal. Since the first conversion module and the second conversion module are symmetrical structures, when the slave sends a communication signal to the host, the host signal output end can be directly replaced by the host signal input end, and the slave signal input end can be replaced by the slave signal output end, which is not elaborated one by one in this embodiment.

[0094] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0095] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0096] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A communication transmission circuit, characterized in that: include: A first conversion module and a second conversion module, wherein the first conversion module includes a low level input terminal and a high level output terminal, and the second conversion module includes a high level input terminal and a low level output terminal; The low level input terminal is connected to the host signal output terminal, the high level output terminal is connected to the high level input terminal, and the low level output terminal is connected to the slave signal input terminal.

2. The communication transmission circuit according to claim 1, characterized in that: The first conversion module includes a first switch unit, a first current limiting unit, a first pull-up unit, a second current limiting unit and a second pull-up unit; The first end and the second end of the first switch unit are both pulled up to a first voltage via the first pull-up unit; The second end of the first switch unit is also connected to the host signal output end via the first current limiting unit; the third end of the first switch unit is pulled up to a second voltage via the second pull-up unit; The third terminal of the first switch unit is connected to the high level input terminal via the second current limiting unit.

3. The communication transmission circuit according to claim 2, characterized in that: The second conversion module includes a second switch unit, a third current limiting unit, a third pull-up unit, a fourth current limiting unit and a fourth pull-up unit; The first end and the second end of the second switch unit are both pulled up to a third voltage via the third pull-up unit; The second end of the second switch unit is also connected to the slave signal input end via the third current limiting unit; the third end of the second switch unit is pulled up to a fourth voltage via the fourth pull-up unit; The third terminal of the second switch unit is connected to the high level output terminal via the fourth current limiting unit.

4. The communication transmission circuit according to claim 3, characterized in that: The first switch unit includes a first transistor, the second switch unit includes a second transistor, the first pull-up unit includes a first resistor and a second resistor, and the third pull-up unit includes a third resistor and a fourth resistor; wherein the first end of the first transistor is pulled up to a first voltage via the first resistor, and the second end of the first transistor is pulled up to a first voltage via the second resistor; The first terminal of the second transistor is pulled up to a third voltage via the third resistor, and the second terminal of the second transistor is pulled up to a third voltage via the fourth resistor.

5. The communication transmission circuit according to claim 4, characterized in that: The first voltage is equal to the third voltage, and the second voltage is equal to the fourth voltage.

6. The communication transmission circuit according to claim 2 or 3, characterized in that: Also includes: An electrostatic protection module is connected to the low level input terminal, the high level output terminal, the high level input terminal and the low level output terminal respectively.

7. The communication transmission circuit according to claim 6, characterized in that: The electrostatic protection module includes a first diode, a second diode, a third diode, and a fourth diode; One end of the first diode is connected to the low level input end, and the other end of the first diode is grounded; One end of the second diode is connected to the high level output end, and the other end of the second diode is grounded; One end of the third diode is connected to the high level input end, and the other end of the third diode is grounded; One end of the fourth diode is connected to the low level output end, and the other end of the fourth diode is grounded.

8. The communication transmission circuit according to claim 7, characterized in that: The first diode, the second diode, the third diode and the fourth diode are all electrostatic protection diodes.

9. A communication transmission system, characterized in that: The invention comprises a host, a slave and the communication transmission circuit according to any one of claims 1 to 8, wherein the host is communicatively connected with the slave via the communication transmission circuit.

10. An electronic device, characterized in that: Comprising a communication transmission system according to claim 9.

Images