Full-passive device, multi-protocol and high-speed data on-off switching circuit
By using a completely passive device design and combining MCU GPIO ports and resistors, a low-cost, small-footprint, high-speed data on/off control is achieved, solving the problem of high cost and large footprint of dedicated data switch ICs, and supporting multi-protocol communication.
Patent Information
- Application Number
- CN202423227267.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-26
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2034-12-26
AI Technical Summary
In existing embedded circuit systems, using dedicated data switch ICs to implement data on/off and isolation functions is costly, requires a large footprint, and increases the difficulty of board layout.
The design employs all passive components, utilizing the GPIO ports or OC gate output ports of the MCU in combination with resistors to achieve data connection and disconnection control between devices. By controlling the input/output direction conversion of the GPIO, high-speed data connection and disconnection and isolation are achieved.
It achieves low-cost, small-footprint data on/off control, supports multi-protocol communication, is suitable for various circuit systems, and replaces dedicated data switch ICs.
Smart Images
Figure CN223728238U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to a switch circuit technical field, concretely is a kind of full passive device, multi-protocol, high-speed data on-off switch circuit. BACKGROUND
[0002] In many embedded circuit systems, digital communication switching is needed to realize the on-off function of data transmission or the controllable isolation function of data, and at present, dedicated data switch IC or 74 gate circuit is basically used to realize isolation, and the shortcomings are higher price and PCB area, which increases the difficulty of board layout. UTILITY MODEL CONTENT
[0003] The technical problem to be solved by the utility model is to overcome the above technical defects, and provide a kind of full passive device, multi-protocol, high-speed data on-off switch circuit box.
[0004] In order to solve the above problems, the technical scheme of the utility model is as follows: a kind of full passive device, multi-protocol, high-speed data on-off switch circuit, including the control body MCU of embedded system and two devices needing data communication, two devices are divided into A and B, and two devices are connected with MCU, two devices are connected in series, and two devices are provided with resistance between MCU, two resistances are R1 and R2.
[0005] Further, the MCU is provided with a plurality of output ports, and the output port is any one of GPIO port, OC gate output port and tri-state port.
[0006] Further, the resistance of the series connection of the resistance R1 and R2 is less than the input impedance of the device A / B, and the resistance after series connection is ≤10% of the input impedance.
[0007] Further, the output capacity of the output port of the MCU is greater than Wherein, R 并 When the resistance R1 / R2 is low on both sides, the voltage drop of GPI0 output is <10%*Vcc, and the output high level of the device is =V CC .
[0008] Further, the output capacity of the device A / B is greater than Wherein, R is R1 or R2, and when R1 or R2 is grounded, the high level drop of the device A / B output is <10%*Vcc.
[0009] Further, the combination of a plurality of the above circuits realizes the cut-off and transfer of multi-port data communication, realizes the effect of traditional multi-blade multi-pole switch IC, and constitutes flexible, inexpensive, convenient multi-port, multi-device communication system.
[0010] The utility model discloses a switch circuit, which is characterized by the following: the utility model utilizes the output port of the common MCU in the circuit system to realize the on-off control of high-speed data, realizes the purpose of controllable data isolation, and has no limitation on the communication speed of data and the communication protocol, and the land occupation of the whole circuit is extremely small, and the cost is extremely low, so the utility model can be widely used in occasions requiring data on-off control and replace the special data switch IC. BRIEF DESCRIPTION OF DRAWINGS
[0011] Figure 1 It is the schematic diagram of the switch circuit of the utility model.
[0012] Figure 2 It is the data communication gating control schematic diagram between equipment A and B / C of the utility model.
[0013] Figure 3 It is the MCU driving capacity expansion schematic diagram of the utility model. DETAILED DESCRIPTION
[0014] The technical scheme in the embodiments of the utility model will be described clearly and completely in combination with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the person skilled in the art without creative labor belong to the protection scope of the utility model.
[0015] As shown in the figure, equipment A / B is the equipment main body requiring bidirectional data communication, and the MCU is the control body of the embedded system, and the communication between equipment A / B needs to be controlled to keep communication or be cut off, and the on-off control of data is completed by the software of the MCU. Figure 1 The software of the MCU controls the input / output direction state of the bidirectional GPIO, and the output high level of the equipment = V CC When the GPIO is modified to the input high resistance state, the communication of the data equipment A / B keeps unblocked, the communication direction is bidirectional and unrestricted, and the communication rate is unrestricted, and when the communication between A / B needs to be cut off, the MCU commands the GPIO to be modified to the output state, and the output high / low level can be even, at this time, the GPIO changes into a constant voltage source, and the data communication between A / B is interrupted.
[0016] Only the input / output direction of the bidirectional GPIO needs to be continuously modified, or the OC gate or tri-state port is adopted to realize the output / high resistance state conversion, so that the on and off of the bidirectional data communication between the data equipment A / B can be realized, and the on-off control process is very short, the extremely high-speed data on-off control can be realized, and the communication rate is unrestricted.
[0017]
[0018] The switch circuit is suitable for various circuit systems with MCU, and uses the 1-way or n-way GPIO port of the MCU as a control port according to needs, so as to realize on / off control of communication between multiple devices and switching control of communication between multiple devices. Meanwhile, the switch circuit is suitable for occasions with the needs of on / off control, communication isolation control and multi-way communication switching control of digital communication between multiple devices, supports various common communication protocols on the market, such as UART, 485, I2C, SPI, CAN and the like, and basically does not limit the communication protocol itself.
[0019] The output driving capability of the GPIO of the MCU of the switch circuit has certain needs, and the common output capability requirement is 5mA-10mA circuit output and suction capability (or higher), as shown in the following formula: Figure 2 The data communication gating control between devices A and B / C is as follows:
[0020] The GPIO2 outputs a high level, the GPIO1 inputs a high resistance state, communication between A and B is realized, and A and C are isolated.
[0021] The GPIO1 outputs a high level, the GPIO2 inputs a high resistance state, communication between A and C is realized, and A and B are isolated.
[0022] However, for some MCUs with weak port line driving capability, the driving capability expansion mode of an external transistor can also be used, and only a low-cost transistor needs to be added, as shown in the following formula: Figure 3
[0023] Figure 3 3a in the formula is an MCU driving capability expansion mode 1, wherein MCU output high level = off communication between A / B, and MCU output low level = restore communication between A / B.
[0024] Figure 3 3b in the formula is an MCU driving capability expansion mode 2, wherein MCU output high level = restore communication between A / B, and MCU output low level = off communication between A / B.
[0025] The input / output direction conversion of the GPIO port is controlled by the MCU / CPU, or an OC gate or a tri-state port is used, so as to realize the conversion of the GPIO port between the output voltage source and the input high resistance state, thereby realizing the on / off control and channel switching control of digital communication between multiple devices. Through the combination of multiple ways of the circuit, the on / off control of multi-way data communication or the communication switching function between multiple devices of digital circuit communication can be realized, the ability of a multi-way active digital switching switch IC is realized, and the parallel number of communication required circuits is not limited, which can be from 1-way communication to n-way communication, and is limited only by the number of GPIOs that can be provided by the MCU / CPU.
[0026] The non-disclosed parts in the utility model are all prior arts, and the specific structure and working principle are not described again.
[0027] It should be noted that, in this document, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus.
[0028] Although the embodiments of the utility model have been shown and described, it should be understood by those of ordinary skill in the art that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirit of the utility model, and the scope of the utility model is defined by the appended claims and their equivalents.
[0029] The utility model and its implementation mode have been described above, and this description is not restrictive, and the embodiment shown in the drawings is only one of the embodiments of the utility model, and the actual structure is not limited thereto. In summary, if a person of ordinary skill in the art is inspired, without departing from the creative purpose of the utility model, without creative design, similar structure modes and embodiments of the technical scheme should belong to the protection scope of the utility model.
Claims
1. An all-passive device, multi-protocol, high-speed data pass-through switch circuit, characterized by: The control body MCU of the embedded system and two devices needing data communication are included, the two devices are divided into A and B, and the two devices are connected with the MCU, the two devices are connected in series, and the two devices are provided with resistors between the two devices and the MCU, and the two resistors are R1 and R2.
2. A fully passive, multi-protocol, high-speed data pass-through switch circuit according to claim 1, wherein: The MCU is provided with a plurality of output ports, and the output port is any one of a GPIO port, an OC gate output port and a tri-state port.
3. A fully passive, multi-protocol, high-speed data pass-through switch circuit according to claim 2, wherein: The resistance of the resistors R1 and R2 connected in series is smaller than the input impedance of the devices A / B.
4. A fully passive, multi-protocol, high-speed data pass-through switch circuit according to claim 3, wherein: The output capability of the output port of the MCU is greater than wherein R 并 is the resistance value of R1 and R2 in parallel.
5. A fully passive, multi-protocol, high-speed data pass-through switch circuit according to claim 4, wherein: Device A / B output capability greater than wherein R is R1or R2.