Level conversion circuit and electronic device
Patent Information
- Application Number
- CN202522521177.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-27
- Publication Date
- 2026-11-03
- Estimated Expiration
- 2035-11-27
AI Technical Summary
In existing technologies, when modules with different operating voltages communicate, the communication incompatibility problem cannot be effectively solved, leading to damage or unrecognizable I/O ports of the modules and resulting in communication errors.
By using optocouplers to perform electrical connections, communication level conversion between two modules with different operating voltages is achieved. This avoids damage to the module's I/O ports due to communication levels exceeding the maximum voltage stress of the I/O ports, or communication errors caused by communication levels that are too low to be recognized, thereby improving communication compatibility between different modules.
This system enables communication level conversion between two modules operating at different voltages, preventing damage to module I/O ports and communication errors, improving communication compatibility between modules and circuit safety, and meeting safety regulations.
Smart Images
Figure CN224935660U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of electronic technology, and in particular to a level conversion circuit and electronic device. Background Technology
[0002] Electronic devices typically include multiple modules operating at different voltages. When two modules with different operating voltages need to communicate, such as a 5V module transmitting a signal to a 3.3V module, if the signal level is not converted, directly connecting the 5V module's I / O port to the 3.3V module's I / O port will transmit a 5V signal, exceeding the 3.3V module's maximum voltage stress (typically 3.6V), potentially damaging the I / O port. Conversely, while there's no voltage stress issue when a 3.3V module transmits a signal to a 5V module, the transmitted signal is only 3.3V, which the 5V module may not recognize, leading to communication errors.
[0003] Therefore, there is an urgent need to propose new solutions to address the communication incompatibility issue between modules with different operating voltages. Utility Model Content
[0004] This application provides a level conversion circuit and electronic device that can realize communication level conversion between two modules with different operating voltages, avoid damaging the module's I / O ports or causing communication errors, and improve communication compatibility between different modules.
[0005] This application provides a level conversion circuit, including a first communication module having a first operating voltage and a second communication module having a second operating voltage. The first operating voltage is different from the second operating voltage. The first communication module includes a first signal transmitting port, a first signal receiving port and a first optocoupler. The second communication module includes a second signal transmitting port, a second signal receiving port and a second optocoupler. The first signal receiving port communicates with the second signal transmitting port. The first signal receiving port is connected to a first power supply with the first operating voltage and is also connected to the second optocoupler. The second signal receiving port communicates with the first signal transmitting port, the second signal receiving port is connected to a second power supply having the second operating voltage, and is connected to the first optocoupler; When the first signal transmitting port transmits a high level, the first optocoupler is turned off, and the second signal receiving port receives the second operating voltage; when the first signal transmitting port transmits a low level, the first optocoupler is turned on, and the second signal receiving port is grounded through the first optocoupler to receive a low level. When the second signal transmitting port transmits a high level, the second optocoupler is turned off, and the first signal receiving port receives the first operating voltage; when the second signal transmitting port transmits a low level, the second optocoupler is turned on, and the first signal receiving port is grounded through the second optocoupler to receive a low level.
[0006] In some embodiments, the first optocoupler includes a first input terminal, a second input terminal, a first output terminal, and a second output terminal; The first input terminal is connected to the first power supply, the second input terminal is connected to the first signal transmitting port, the first output terminal is grounded, and the second output terminal is connected to the second signal receiving port.
[0007] In some embodiments, a first current-limiting resistor is connected between the first input terminal and the first power supply.
[0008] In some embodiments, the first signal receiving port is connected to the first power supply via a first pull-up resistor.
[0009] In some embodiments, the second optocoupler includes a third input terminal, a fourth input terminal, a third output terminal, and a fourth output terminal; The third input terminal is connected to the second power supply, the fourth input terminal is connected to the second signal transmitting port, the third output terminal is grounded, and the fourth output terminal is connected to the first signal receiving port.
[0010] In some embodiments, a second current-limiting resistor is connected between the third input terminal and the second power supply.
[0011] In some embodiments, the second signal receiving port is connected to the second power supply via a second pull-up resistor.
[0012] In some embodiments, the first communication module includes a first controller, the first signal transmitting port and the first signal receiving port are the transmitting port and receiving port of the first controller, and the first controller further includes a first power port, which is connected to the first power source.
[0013] In some embodiments, the second communication module includes a second controller, the second signal transmitting port and the second signal receiving port are the transmitting port and receiving port of the second controller, and the second controller further includes a second power port, which is connected to the second power source.
[0014] This application also provides an electronic device including the level conversion circuit of any of the above embodiments.
[0015] The level conversion circuit of this application embodiment can realize the communication level conversion between two modules with different operating voltages, namely the first communication module and the second communication module, to avoid damage to the module's I / O port due to the communication level exceeding the maximum voltage stress of the I / O port, or communication errors caused by the communication level voltage being too low to be recognized, thereby improving the communication compatibility between different modules.
[0016] On the other hand, the communication level between the first communication module and the second communication module is transmitted through an optocoupler. There is no direct electrical connection between the first communication module and the second communication module. When one of the communication modules is affected by factors such as high voltage surges or electromagnetic interference, the other communication module will not be affected due to the isolation provided by the optocoupler. This improves the overall circuit safety and meets safety regulations. Attached Figure Description
[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0018] Figure 1 This is a schematic diagram of the level conversion circuit according to an embodiment of this application. Detailed Implementation
[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.
[0020] This application provides a level conversion circuit that can realize communication level conversion between two modules with different operating voltages, such as communication level conversion between a 3.3V module and a 5V module.
[0021] refer to Figure 1 , Figure 1 This is a schematic diagram of the level conversion circuit according to an embodiment of this application. The level conversion circuit includes a first communication module 10 and a second communication module 40.
[0022] The first communication module 10 has a first operating voltage, and the second communication module 40 has a second operating voltage. The first operating voltage and the second operating voltage are different. For example, in one example, the first operating voltage can be 3.3V, and the second operating voltage can be 5V. It should be noted that the above-mentioned operating voltages of 3.3V and 5V are merely examples and do not constitute a limitation on the technical solution of this application. In practical applications, the first operating voltage and the second operating voltage can also be other voltage values.
[0023] The first communication module 10 includes a first signal transmitting port, a first signal receiving port, and a first optocoupler, such as a first optocoupler 11. The second communication module 40 includes a second signal transmitting port, a second signal receiving port, and a second optocoupler 41.
[0024] In some embodiments, the first communication module 10 includes a first controller U1, which may be a microcontroller unit (MCU). Figure 1 The MCU is represented in the diagram. The first signal transmitting port and the first signal receiving port are the transmitting and receiving ports of the first controller U1. For example... Figure 1 As shown, the transmitting port of the first controller U1 can be represented as TX, and the receiving port can be represented as RX.
[0025] The first controller U1 also includes a first power port, such as Figure 1 The first power supply port VCC of the first controller U1 is shown. The first power supply port VCC is connected to a first power source. The first power source has a first operating voltage, for example, a 3.3V power source. The first power source supplies power to the first controller U1 through the first power supply port VCC.
[0026] In some embodiments, the first controller U1 further includes a first ground port, a first input / output port, and a second input / output port, such as... Figure 1 The first controller U1 shown has a first ground port GND, a first input / output port IO1, and a second input / output port IO2. The first ground port GND is grounded, for example, connected to ground HGND. The first input / output port IO1 and the second input / output port IO2 are used to implement signal input and output. In one example, the first input / output port IO1 can be an INT port, and the second input / output port IO2 can be an ADC port.
[0027] In some embodiments, the second communication module 40 includes a second controller U4, which may be an MCU. Figure 1The MCU is represented in the diagram. The second signal transmitting port and the second signal receiving port are the transmitting and receiving ports of the second controller U4. For example... Figure 1 As shown, the transmitting port of the second controller U4 can be represented as TX, and the receiving port can be represented as RX.
[0028] The second controller U4 also includes a second power port, such as Figure 1 The second power supply port VCC of the second controller U4 is shown. The second power supply port VCC is connected to a second power source. The second power source has a second operating voltage, for example, it can be a 5V power source. The second power source supplies power to the second controller U4 through the second power supply port VCC.
[0029] In some embodiments, the second controller U4 further includes a second ground port, a third input / output port, and a fourth input / output port, such as... Figure 1 The second controller U4 shown has a second ground port GND, a third input / output port IO1, and a fourth input / output port IO2. The second ground port GND is grounded, for example, connected to ground LGND. The third input / output port IO1 and the fourth input / output port IO2 are used to implement signal input and output. In one example, the third input / output port IO1 can be an INT port, and the fourth input / output port IO2 can be an ADC port.
[0030] The first signal receiving port of the first communication module 10 communicates with the second signal transmitting port of the second communication module 40, for example, the RX port of the first controller U1 communicates with the TX port of the second controller U4. The first signal receiving port (e.g., the RX port of U1) is connected to a first power supply, for example, a 3.3V power supply, and the first signal receiving port (e.g., the RX port of U1) is connected to the second optocoupler 41. Figure 1 In this context, RX1 represents the signal transmitted between the first signal receiving port (e.g., the RX port of U1) and the second optocoupler 41.
[0031] The second signal receiving port of the second communication module 40 communicates with the first signal transmitting port of the first communication module 10, for example, the RX port of the second controller U4 communicates with the TX port of the first controller U1. The second signal receiving port (e.g., the RX port of U4) is connected to a second power supply, for example, a 5V power supply, and the second signal receiving port (e.g., the RX port of U4) is connected to the first optocoupler 11. Figure 1 In this context, RX2 represents the signal transmitted between the second signal receiving port (e.g., the RX port of U4) and the first optocoupler 11.
[0032] In some embodiments, such as Figure 1As shown, the first optocoupler 11 is designated U2. The first optocoupler 11 includes a first input terminal 21, a second input terminal 22, a first output terminal 23, and a second output terminal 24. The first input terminal 21 is connected to a first power supply (e.g., a 3.3V power supply). The second input terminal 22 is connected to a first signal transmitting port (e.g., the TX port of U1). The first output terminal 23 is grounded, for example, connected to ground LGND. The second output terminal 24 is connected to a second signal receiving port (e.g., the RX port of U4). In practical applications, the first input terminal 21 can be the anode of a light-emitting diode (LED), and the second input terminal 22 can be the cathode of an LED; the first output terminal 23 can be the emitter of a phototransistor, and the second output terminal 24 can be the collector of a phototransistor.
[0033] In some embodiments, a first current-limiting resistor R2 is connected between the first input terminal 21 and a first power supply (e.g., a 3.3V power supply). In one example, the resistance value of the first current-limiting resistor R2 is 1kΩ.
[0034] In some embodiments, the first signal receiving port (e.g., the RX port of U1) is connected to a first power supply (e.g., a 3.3V power supply) via a first pull-up resistor R1. In one example, the resistance value of the first pull-up resistor R1 is 10kΩ.
[0035] In some embodiments, such as Figure 1 As shown, the second optocoupler 41 is designated U3. The second optocoupler 41 includes a third input terminal 31, a fourth input terminal 32, a third output terminal 33, and a fourth output terminal 34. The third input terminal 31 is connected to a second power supply (e.g., a 5V power supply). The fourth input terminal 32 is connected to a second signal transmitting port (e.g., the TX port of U4). The third output terminal 33 is grounded, for example, connected to ground (HGND). The fourth output terminal 34 is connected to a first signal receiving port (e.g., the RX port of U1). In practical applications, the third input terminal 31 can be the anode of a light-emitting diode (LED), and the fourth input terminal 32 can be the cathode of an LED; the third output terminal 33 can be the emitter of a phototransistor, and the fourth output terminal 34 can be the collector of a phototransistor.
[0036] In some embodiments, a second current-limiting resistor R3 is connected between the third input terminal 31 and the second power supply (e.g., a 5V power supply). In one example, the resistance value of the second current-limiting resistor R3 is 1kΩ.
[0037] In some embodiments, the second signal receiving port (e.g., the RX port of U4) is connected to a second power supply (e.g., a 5V power supply) via a second pull-up resistor R4. In one example, the resistance value of the second pull-up resistor R4 is 10kΩ.
[0038] The working principle of the level conversion circuit in this embodiment is as follows: When the first signal transmitting port (e.g., the TX port of U1) transmits a high level, since the first communication module 10 operates at a first operating voltage, such as 3.3V, the transmitted high level is 3.3V. Both ends of the LED of the first optocoupler 11 are at a high level of 3.3V, the LED is off, and the phototransistor is also off. Therefore, the first optocoupler 11 is off. At this time, the second signal receiving port (e.g., the RX port of U4) inputs the second operating voltage of the second power supply (e.g., a 5V power supply), such as 5V, achieving a high-level input. When the first signal transmitting port (e.g., the TX port of U1) transmits a low level, the anode of the LED of the first optocoupler 11 is at a high level, and the cathode is at a low level. The LED is on, and the phototransistor is also on. Therefore, the first optocoupler 11 is on. The second signal receiving port (e.g., the RX port of U4) is grounded through the first optocoupler 11 to input a low level, achieving a low-level input. Therefore, it is possible to achieve level conversion between the first signal transmitting port (e.g., the TX port of U1) and the second signal receiving port (e.g., the RX port of U4).
[0039] When the second signal transmitting port (e.g., the TX port of U4) transmits a high level, since the second communication module 40 operates at a second operating voltage, such as 5V, the transmitted high level is 5V. Both ends of the LED of the second optocoupler 41 are at a high level of 5V, the LED is off, and the phototransistor is also off. Therefore, the second optocoupler 41 is off. At this time, the first signal receiving port (e.g., the RX port of U1) receives the first operating voltage of the first power supply (e.g., 3.3V), achieving a high-level input. When the second signal transmitting port (e.g., the TX port of U4) transmits a low level, the anode of the LED of the second optocoupler 41 is at a high level, and the cathode is at a low level. The LED conducts, and the phototransistor also conducts. Therefore, the second optocoupler 41 conducts, and the first signal receiving port (e.g., the RX port of U1) is grounded through the second optocoupler 41 to receive a low level, achieving a low-level input. Therefore, level conversion between the second signal transmitting port (e.g., the TX port of U4) and the first signal receiving port (e.g., the RX port of U1) can be achieved.
[0040] The level conversion circuit of this application embodiment can realize the communication level conversion between two modules with different operating voltages, namely the first communication module 10 and the second communication module 40, to avoid damage to the module's I / O port due to the communication level exceeding the maximum voltage stress of the I / O port, or communication errors caused by the communication level being too low to be recognized, thereby improving the communication compatibility between different modules.
[0041] On the other hand, the communication level between the first communication module 10 and the second communication module 40 is transmitted through optocouplers (first optocoupler 11 and second optocoupler 41). There is no direct electrical connection between the first communication module 10 and the second communication module 40. When one of the communication modules is affected by factors such as high voltage surges or electromagnetic interference, the other communication module will not be affected due to the isolation provided by the optocouplers. This improves the overall circuit safety and meets safety regulations.
[0042] This application also provides an electronic device including the level conversion circuit of any of the above embodiments.
[0043] In the description of this application, it should be understood that terms such as “first” and “second” are used only to distinguish similar objects and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated.
[0044] It should be noted that in the embodiments of this application, "connection" can be understood as electrical connection. The connection between two electrical components can be a direct or indirect connection between the two electrical components. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components.
[0045] The level conversion circuit and electronic device provided in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only for the purpose of helping to understand this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.
Claims
1. A level conversion circuit, characterized in that, The device includes a first communication module having a first operating voltage and a second communication module having a second operating voltage, wherein the first operating voltage is different from the second operating voltage. The first communication module includes a first signal transmitting port, a first signal receiving port and a first optocoupler, and the second communication module includes a second signal transmitting port, a second signal receiving port and a second optocoupler. The first signal receiving port communicates with the second signal transmitting port. The first signal receiving port is connected to a first power supply with the first operating voltage and is also connected to the second optocoupler. The second signal receiving port communicates with the first signal transmitting port, the second signal receiving port is connected to a second power supply having the second operating voltage, and is connected to the first optocoupler; When the first signal transmitting port transmits a high level, the first optocoupler is turned off, and the second signal receiving port receives the second operating voltage; when the first signal transmitting port transmits a low level, the first optocoupler is turned on, and the second signal receiving port is grounded through the first optocoupler to receive a low level. When the second signal transmitting port transmits a high level, the second optocoupler is turned off, and the first signal receiving port receives the first operating voltage; when the second signal transmitting port transmits a low level, the second optocoupler is turned on, and the first signal receiving port is grounded through the second optocoupler to receive a low level.
2. The level conversion circuit according to claim 1, characterized in that, The first optocoupler includes a first input terminal, a second input terminal, a first output terminal, and a second output terminal; The first input terminal is connected to the first power supply, the second input terminal is connected to the first signal transmitting port, the first output terminal is grounded, and the second output terminal is connected to the second signal receiving port.
3. The level conversion circuit according to claim 2, characterized in that, A first current-limiting resistor is connected between the first input terminal and the first power supply.
4. The level conversion circuit according to claim 1, characterized in that, The first signal receiving port is connected to the first power supply via a first pull-up resistor.
5. The level conversion circuit according to claim 1, characterized in that, The second optocoupler includes a third input terminal, a fourth input terminal, a third output terminal, and a fourth output terminal; The third input terminal is connected to the second power supply, the fourth input terminal is connected to the second signal transmitting port, the third output terminal is grounded, and the fourth output terminal is connected to the first signal receiving port.
6. The level conversion circuit according to claim 5, characterized in that, A second current-limiting resistor is connected between the third input terminal and the second power supply.
7. The level conversion circuit according to claim 1, characterized in that, The second signal receiving port is connected to the second power supply via a second pull-up resistor.
8. The level conversion circuit according to any one of claims 1 to 7, characterized in that, The first communication module includes a first controller, the first signal transmitting port and the first signal receiving port are the transmitting port and receiving port of the first controller, and the first controller also includes a first power port, which is connected to the first power source.
9. The level conversion circuit according to any one of claims 1 to 7, characterized in that, The second communication module includes a second controller, the second signal transmitting port and the second signal receiving port are the transmitting port and receiving port of the second controller, and the second controller also includes a second power port, which is connected to the second power source.
10. An electronic device, characterized in that, Includes the level conversion circuit according to any one of claims 1 to 9.