CN107168901B - Single-wire bidirectional communication circuit - Google Patents
Single-wire bidirectional communication circuit Download PDFInfo
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- CN107168901B CN107168901B CN201610130662.XA CN201610130662A CN107168901B CN 107168901 B CN107168901 B CN 107168901B CN 201610130662 A CN201610130662 A CN 201610130662A CN 107168901 B CN107168901 B CN 107168901B
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/40—Bus networks
- H04L12/40006—Architecture of a communication node
- H04L12/40032—Details regarding a bus interface enhancer
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F13/00—Interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units
- G06F13/14—Handling requests for interconnection or transfer
- G06F13/20—Handling requests for interconnection or transfer for access to input/output bus
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/40—Bus networks
- H04L2012/40267—Bus for use in transportation systems
- H04L2012/40273—Bus for use in transportation systems the transportation system being a vehicle
Abstract
A single-wire bidirectional communication circuit comprises an output module and an input module, wherein the output module and the input module are connected with input and output pins of a control center, the output module comprises a power supply unit, a modulation unit, a first diode and a second diode, the first diode is connected between the power supply unit and the input and output pins of the control center, and the second diode is connected between the modulation unit and the input and output pins of the control center and used for protecting the single-wire bidirectional communication circuit.
Description
Technical Field
The invention relates to a single-wire bidirectional communication circuit.
Background
An Electronic Control Unit (ECU) of an automobile, also called a "traveling computer" or a "vehicle-mounted computer", is used as a special microcomputer controller for the automobile, and can exchange and Control data with an instrument panel, AT, EBS, and the like through a bus technology. The bus may be three-wire or four-wire, specifically, the four-wire type bus is composed of a power line, a ground line, an input signal line and an output signal line, and the three-wire type bus is composed of a power line, a ground line and a signal line, wherein the signal line needs to satisfy bidirectional communication to realize input and output of signals.
The existing communication circuit for realizing signal input and output by signal lines in a three-wire type bus usually lacks a protection function, for example, the circuit is damaged and cannot work when a power supply is reversely plugged. In addition, such a communication circuit also has a problem of signal instability, that is, when external conditions change, the voltage of an input or output level signal is unstable, and when the voltage is serious, the input or output signal cannot be identified.
Disclosure of Invention
In view of the above, the present invention provides a single-wire bidirectional communication circuit with protection function.
A single-wire bidirectional communication circuit is used for being connected with a control center to exchange data in a real-time bidirectional mode, the control center comprises an input/output pin, the single-wire bidirectional communication circuit comprises an output module and an input module, the output module and the input module are both connected with the input/output pin of the control center, the output module is connected with the input/output pin of the control center and used for sending a first signal to the control center, the input module is connected with the input/output pin of the control center and used for receiving a second signal from the control center, the output module comprises a power supply unit, a modulation unit, a first diode and a second diode, the power supply unit is used for providing a power supply signal to the modulation unit, the modulation unit is used for converting the signal and outputting the signal to the control center, the anode of the first diode is connected with the power supply unit, the cathode of the first diode is connected with the input/output pin of the control center, the cathode of the second diode is connected with the modulation unit, and the anode of the second diode is connected with the input/output pin of the control center.
Furthermore, the output module further comprises a control unit, and the control unit is connected between the power supply unit and the modulation unit and is used for receiving the signal from the modulation unit to control the power supply unit to work.
Furthermore, the power supply unit comprises a first electronic switch, a first resistor and a second resistor, wherein the control end of the first electronic switch is grounded through the first resistor, the first end of the first electronic switch is connected with the anode of the first diode, and the second end of the first electronic switch is connected with a first power supply through the second resistor; when the control end of the first electronic switch receives a high level signal, the first end and the second end of the first electronic switch are disconnected, and when the control end of the first electronic switch receives a low level signal, the first end and the second end of the first electronic switch are connected.
Furthermore, the power supply unit comprises a first electronic switch, a first resistor and a second resistor, wherein the control end of the first electronic switch is connected with the modulation unit through the first resistor, the first end of the first electronic switch is connected with the anode of the first diode, and the second end of the first electronic switch is connected with a first power supply through the second resistor; when the modulation unit outputs a high level signal, the first end and the second end of the first electronic switch are disconnected, and when the modulation unit outputs a low level signal, the first end and the second end of the first electronic switch are connected.
Furthermore, the power supply unit comprises a first electronic switch, a first resistor and a second resistor, wherein the control end of the first electronic switch is connected with the control unit through the first resistor, the first end of the first electronic switch is connected with the anode of the first diode, and the second end of the first electronic switch is connected with a first power supply through the second resistor; when the modulation unit outputs a high level signal, the first end and the second end of the first electronic switch are disconnected, and when the modulation unit outputs a low level signal, the first end and the second end of the first electronic switch are connected.
Furthermore, the power supply unit further includes a third resistor and a third diode, an anode of the third diode is connected to the first power supply through the third resistor, and a cathode of the third diode is connected to the control terminal of the first electronic switch.
Further, the first electronic switch is a PNP type triode.
Furthermore, the modulation unit includes a second electronic switch, a fourth resistor and a fifth resistor, a control terminal of the second electronic switch is connected to a transmitting terminal through the fourth resistor, a first terminal of the second electronic switch is connected to a cathode of the second diode, and a second terminal of the second electronic switch is grounded through the fifth resistor; when the control end of the second electronic switch receives a low level signal, the first end and the second end of the second electronic switch are disconnected, and when the control end of the second electronic switch receives a high level signal, the first end and the second end of the second electronic switch are connected; the transmitting end is used for transmitting the first signal.
Furthermore, the modulation unit includes a second electronic switch, a fourth resistor and a fifth resistor, a control end of the second electronic switch is connected to a transmitting end through the fourth resistor, the transmitting end is further connected to the power supply unit, a first end of the second electronic switch is connected to a cathode of the second diode, and a second end of the second electronic switch is grounded through the fifth resistor; when the control end of the second electronic switch receives a low level signal, the first end and the second end of the second electronic switch are disconnected, and when the control end of the second electronic switch receives a high level signal, the first end and the second end of the second electronic switch are connected; the transmitting end is used for transmitting the first signal.
Furthermore, the modulation unit includes a second electronic switch, a fourth resistor and a fifth resistor, a control end of the second electronic switch is connected to a transmitting end through the fourth resistor, the transmitting end is further connected to the control unit, a first end of the second electronic switch is connected to a cathode of the second diode, and a second end of the second electronic switch is grounded through the fifth resistor; when the control end of the second electronic switch receives a low level signal, the first end and the second end of the second electronic switch are disconnected, and when the control end of the second electronic switch receives a high level signal, the first end and the second end of the second electronic switch are connected; the transmitting end is used for transmitting the first signal.
Furthermore, the modulation unit further includes a sixth resistor and a fourth diode, an anode of the fourth diode is connected to the control terminal of the second electronic switch, and a cathode of the fourth diode is grounded through the sixth resistor.
Further, the second electronic switch is an NPN-type triode.
Furthermore, the input module comprises a seventh resistor and a voltage stabilizing diode, an input/output pin of the control center is connected with a receiving end through the seventh resistor, a cathode of the voltage stabilizing diode is connected with the receiving end, and an anode of the voltage stabilizing diode is grounded; the receiving end is used for receiving the second signal.
Furthermore, the input module further comprises a filtering unit, the filtering unit is connected with the voltage stabilizing diode in parallel, and the filtering unit comprises an eighth resistor and a capacitor which are connected in parallel.
Furthermore, the control unit includes a third electronic switch and a ninth resistor, a control end of the third electronic switch is connected to a second power supply through the ninth resistor, a first end of the third electronic switch is connected to the power supply unit, and a second end of the third electronic switch is connected to the modulation unit; when the control end of the third electronic switch receives a low level signal, the first end and the second end of the third electronic switch are disconnected, and when the control end of the third electronic switch receives a high level signal, the first end and the second end of the third electronic switch are connected.
Further, the third electronic switch is an NPN transistor.
A single-wire bidirectional communication circuit is used for being connected with a control center to exchange data in a real-time bidirectional mode, the control center comprises an input/output pin, the single-wire bidirectional communication circuit comprises an output module and an input module, the output module and the input module are both connected with the input/output pin of the control center, the output module is connected with the input/output pin of the control center and used for sending a first signal to the control center, the output module comprises a power supply unit, a modulation unit, a first protection unit and a second protection unit, the power supply unit is used for providing a power supply signal to the modulation unit, the modulation unit is used for converting the signal and outputting the signal to the control center, the first protection unit is connected between the power supply unit and the input/output pin of the control center to prevent reverse current from damaging the power supply unit, the second protection unit is connected between the modulation unit and an input/output pin of the control center to prevent reverse current from damaging the modulation unit; the input module comprises an input resistor and a voltage stabilizing diode, an input/output pin of the control center is connected with a receiving end through the input resistor, a cathode of the voltage stabilizing diode is connected with the receiving end, an anode of the voltage stabilizing diode is grounded, and the receiving end is used for receiving a second signal from the control center.
Furthermore, the first protection unit comprises a first diode, an anode of the first diode is connected with the power supply unit, and a cathode of the first diode is connected with an input/output pin of the control center.
Furthermore, the second protection unit includes a second diode, a cathode of the second diode is connected to the modulation unit, and an anode of the second diode is connected to the input/output pin of the control center.
Furthermore, the output module further comprises a control unit, and the control unit is connected between the power supply unit and the modulation unit and is used for receiving the signal from the modulation unit to control the power supply unit to work.
Furthermore, the power supply unit comprises a first electronic switch, a first resistor and a second resistor, wherein the control end of the first electronic switch is connected with the control unit through the first resistor, the first end of the first electronic switch is connected with the anode of the first diode, and the second end of the first electronic switch is connected with a first power supply through the second resistor; when the modulation unit outputs a high level signal, the first end and the second end of the first electronic switch are disconnected, when the modulation unit outputs a low level signal, the first end and the second end of the first electronic switch are connected, the power supply unit further comprises a third resistor and a third diode, the anode of the third diode is connected with the first power supply through the third resistor, the cathode of the third diode is connected with the control end of the first electronic switch, and the first electronic switch is a PNP type triode.
Furthermore, the modulation unit comprises a second electronic switch, a fourth resistor and a fifth resistor, a control end of the second electronic switch is connected with a transmitting end through the fourth resistor, the transmitting end is also connected with the control unit, a first end of the second electronic switch is connected with a cathode of a second diode, and a second end of the second electronic switch is grounded through the fifth resistor; when the control end of the second electronic switch receives a low level signal, the first end and the second end of the second electronic switch are disconnected, and when the control end of the second electronic switch receives a high level signal, the first end and the second end of the second electronic switch are connected; the transmitting end is used for transmitting the first signal, the modulation unit further comprises a sixth resistor and a fourth diode, the anode of the fourth diode is connected with the control end of the second electronic switch, the cathode of the fourth diode is grounded through the sixth resistor, and the second electronic switch is an NPN type triode.
Furthermore, the input module further comprises a filtering unit, the filtering unit is connected with the voltage stabilizing diode in parallel, and the filtering unit comprises an eighth resistor and a capacitor which are connected in parallel.
Furthermore, the control unit includes a third electronic switch and a ninth resistor, a control end of the third electronic switch is connected to a second power supply through the ninth resistor, a first end of the third electronic switch is connected to the power supply unit, and a second end of the third electronic switch is connected to the modulation unit; when the control end of the third electronic switch receives a low level signal, the first end and the second end of the third electronic switch are disconnected, and when the control end of the third electronic switch receives a high level signal, the first end and the second end of the third electronic switch are connected, and the third electronic switch is an NPN type triode.
Compared with the prior art, the single-wire bidirectional communication circuit receives the signal sent by the signal output module by the input module, thereby realizing real-time bidirectional communication. Meanwhile, the diode is adopted in the single-wire bidirectional communication circuit to prevent the current in the single-wire bidirectional communication circuit from flowing backwards, so that the circuit is prevented from being damaged by reverse current caused by reverse insertion of a connector due to misoperation of a user.
Drawings
Fig. 1 is a circuit diagram of a first embodiment of a single-wire bidirectional communication circuit of the present invention.
Fig. 2 is a circuit diagram of a second embodiment of the single-wire two-way communication circuit of the present invention.
Detailed Description
Before the embodiments are described in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in other forms of implementation. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of "including," "comprising," "having," and the like, herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. In particular, when "a certain element" is described, the present invention is not limited to the number of the element being one, and may include a plurality of the elements.
Referring to fig. 1, the single-wire bidirectional communication circuit 100 according to the first embodiment of the present invention includes an output module 10 and an input module 30, wherein the output module 10 and the input module 30 are both connected to an input/output pin IO of a control center 200. In this real-time mode, control center 200 may be an automotive electronic control unit, output module 10 connects control center 200's input/output pin IO is used for sending a first signal for control center 200's input/output pin IO, input module 30 connects control center 200's input/output pin IO is used for receiving one and is come from control center 200 input/output pin IO's second signal. In this embodiment, the first and second signals are both Pulse Width Modulation (PWM) signals.
The output module 10 includes a power supply unit 12, a modulation unit 14, and diodes D1, D2. The anode of the diode D1 is connected to the power supply unit 12, and the cathode of the diode D1 is connected to the input/output pin IO of the control center 200. The cathode of the diode D2 is connected to the modulation unit 14, and the anode of the diode D2 is connected to the input/output pin IO of the control center 200.
The power supply unit 12 is configured to provide a power supply signal to the modulation unit 14. The power unit 12 includes a transistor Q1, resistors R1-R3, and a diode D3. In this embodiment, the transistor Q1 is a PNP transistor. The base of the transistor Q1 is grounded through the resistor R1, the collector of the transistor Q1 is connected to the anode of the diode D1, and the emitter of the transistor Q1 is connected to a power Vcc through the resistor R2. The anode of the diode D3 is connected to the power supply Vcc through the resistor R3, and the cathode of the diode D3 is connected to the base of the transistor Q1.
The modulation unit 14 is used for converting signals and outputting the signals to the control center 400. The modulation unit 14 includes a transistor Q2, resistors R4-R6, and a diode D4. In this embodiment, the transistor Q2 is an NPN transistor. The base of the triode Q2 is connected to a transmitting terminal Tx through the resistor R4, the collector of the triode Q2 is connected to the cathode of the diode D2, and the emitter of the triode Q2 is grounded through the resistor R5. The anode of the diode D4 is connected to the base of the transistor Q2, and the cathode of the diode D4 is connected to the ground through the resistor R6. The transmitting end Tx is used to transmit the first signal.
The input module 30 includes a resistor R7, a zener diode D5 and a filtering unit 32, the input/output pin IO of the control center 200 is connected to a receiving terminal Rx through the resistor R7, the cathode of the zener diode D5 is connected to the receiving terminal Rx, and the anode of the zener diode D5 is grounded. The receiving end Rx is configured to receive the second signal. The filter unit 32 is connected in parallel with the zener diode D5, and the filter unit 32 includes a resistor R8 and a capacitor C connected in parallel.
Specifically, when the unidirectional bidirectional communication circuit 100 starts to operate, the power supply Vcc starts to supply power, and the transistor Q1 is turned on. The transmitting terminal Tx outputs the first signal, when the first signal is at a high level, the transistor Q2 is turned on, and the input/output pin IO of the control center 200 receives a low level signal through the resistor R5, the transistor Q2 and the diode D2; when the first signal is at a low level, the transistor Q2 is turned off, and the input/output pin IO of the control center 200 receives a high-level signal of the power Vcc through the resistor R2, the transistor Q1, and the diode D1.
When the input/output pin IO of the control center 200 outputs a second signal, the second signal is stabilized by the resistor R7, the zener diode D5, and filtered by the filtering unit 32, and then output to the receiving terminal Rx, and the receiving terminal Rx receives the second signal.
The diodes D1 and D2 are used for preventing the current in the single-wire bidirectional communication circuit 100 from flowing backwards, and the unidirectional bidirectional communication circuit 100 is damaged by reverse current, so that misoperation of a user, such as circuit damage caused by reverse insertion of a connector, is avoided.
The diode D3 is connected between the base and emitter of the transistor Q1 and is used for temperature compensation of the transistor Q1, so that the on-state current of the transistor Q1 is not affected by environmental changes. Similarly, a diode D4 is connected between the base and emitter of the transistor Q2 for temperature compensating the transistor Q2 so that the on-state current of the transistor Q2 is not affected by environmental changes.
The filtering unit 32 is configured to filter a second signal received by the receiving terminal Rx, so as to avoid damage to the circuit caused by the surge current.
Referring to fig. 2, fig. 2 is a schematic diagram of a unidirectional/bidirectional communication circuit 300 according to a second embodiment of the present invention. The second embodiment of the single-wire bidirectional communication circuit 100 includes an output module 210 and an input module 230, wherein the output module 210 and the input module 230 are both connected to an input/output pin IO of a control center 400. In this embodiment, the control center 400 may be an automotive electronic control unit, the output module 210 is connected to an input/output pin IO of the control center 400 and is used for sending a third signal to the input/output pin IO of the control center 400, and the input module 230 is connected to the input/output pin IO of the control center 400 and is used for receiving a fourth signal from the input/output pin IO of the control center 400. In this embodiment, the third and fourth signals are both Pulse Width Modulation (PWM) signals.
The output module 210 includes a power supply unit 212, a control unit 213, a modulation unit 214, and diodes D21, D22. The anode of the diode D21 is connected to the power supply unit 212, and the cathode of the diode D21 is connected to the input/output pin IO of the control center 400. The cathode of the diode D22 is connected to the modulation unit 214, and the anode of the diode D22 is connected to the input/output pin IO of the control center 400. The control unit 213 is connected between the power supply unit 212 and the modulation unit 214, and is configured to receive a signal from the modulation unit 214 to control whether the power supply unit 212 operates or not.
The power unit 212 includes a transistor Q21, resistors R21-R23, and a diode D23. In this embodiment, the transistor Q21 is a PNP transistor. The base of the transistor Q21 is connected to the control unit 213 through the resistor R21, the collector of the transistor Q21 is connected to the anode of the diode D21, and the emitter of the transistor Q21 is connected to a power source V1 through the resistor R22. The anode of the diode D23 is connected to the power supply V1 through the resistor R23, and the cathode of the diode D23 is connected to the base of the transistor Q21.
The control unit 213 includes a transistor Q23 and a resistor R29. In this embodiment, the transistor Q23 is an NPN transistor. The base of the transistor Q23 is connected to a power supply V2 through the resistor R29, the collector of the transistor Q23 is connected to the base of the transistor Q21 through the resistor R21, and the emitter of the transistor Q23 is connected to the modulation unit 214.
The modulation unit 214 includes a transistor Q22, resistors R24-R26, and a diode D24. In this embodiment, the transistor Q2 is an NPN transistor. The base electrode of the triode Q22 is connected with a transmitting terminal Tx2 through the resistor R24, and the transmitting terminal Tx2 is also connected with the emitting electrode of the triode Q23. The collector of the transistor Q22 is connected to the cathode of the diode D22, and the emitter of the transistor Q22 is connected to ground through the resistor R25. The anode of the diode D24 is connected to the base of the transistor Q22, and the cathode of the diode D24 is connected to the ground through the resistor R26. The transmitting terminal Tx2 is configured to transmit the third signal.
The input module 230 includes a resistor R27, a zener diode D25 and a filtering unit 232, the input/output pin IO of the control center 400 is connected to a receiving terminal Rx2 through the resistor R27, the cathode of the zener diode D25 is connected to the receiving terminal Rx2, and the anode of the zener diode D25 is grounded. The receiving end Rx2 is configured to receive the fourth signal. The filter unit 232 is connected in parallel with the zener diode D25, and the filter unit 232 includes a resistor R28 and a capacitor C2 connected in parallel.
Specifically, when the unidirectional bidirectional communication circuit 300 starts to operate, the power supplies V1 and V2 start to supply power.
The transmitting terminal Tx outputs the third signal, and in this embodiment, the voltage of the power supply signal output by the power supply V2 is equal to or lower than the high voltage of the third signal and higher than the low voltage of the third signal. The voltage of the power supply signal output by the power supply V1 is greater than the high voltage of the third signal. When the third signal is at a high level, at this time, since the voltage of the power signal output by the power source V2 is lower than the third signal, the transistor Q23 is turned off, so that a loop cannot be formed between the base of the transistor Q21 and the transmitter, and the transistor Q21 is turned off. The transistor Q22 is turned on, and the input/output pin IO of the control center 400 receives a low level signal through the resistor R25, the transistor Q22 and the diode D22; when the third signal is at a low level, the transistor Q23 is turned on, the base of the transistor Q21 receives low level signals from the resistor R21 and the transistor Q23, and the transistor Q21 is turned on, the transistor Q22 is turned off, and the input/output pin IO of the control center 400 receives high level signals of the power supply V1 via the resistor R22, the transistor Q21, and the diode D21.
When the fourth signal is output from the input/output pin IO of the control center 400, the fourth signal is stabilized by the resistor R27, the zener diode D25, and filtered by the filtering unit 232 and then output to the receiving terminal Rx2, and the receiving terminal Rx2 receives the fourth signal.
In other embodiments, the power signals from the power sources V1 and V2 may be such that the transistor Q21 is turned off when the third signal is high, and the transistor Q21 is turned on when the third signal is low.
The diodes D21 and D22 are used for preventing the current in the single-wire bidirectional communication circuit 400 from flowing backwards, and the unidirectional bidirectional communication circuit 400 is damaged by reverse current, so that misoperation of a user, such as circuit damage caused by reverse insertion of a connector, is avoided.
The diode D23 is connected between the base and emitter of the transistor Q21 and is used for temperature compensation of the transistor Q21, so that the on-state current of the transistor Q21 is not affected by environmental changes. Similarly, a diode D24 is connected between the base and emitter of the transistor Q22 for temperature compensating the transistor Q22 so that the on-state current of the transistor Q22 is not affected by environmental changes.
The filtering unit 232 is configured to filter the second signal received by the receiving terminal Rx2, so as to avoid damage to the circuit caused by the inrush current.
In this embodiment, the control unit 213 is connected between the power supply unit 212 and the modulation unit 214 for controlling whether the power supply unit 212 operates or not. In another embodiment, when the voltage of the power signal output by the power source V1 is less than or equal to the high voltage of the third signal and greater than the low voltage of the third signal, the control unit 213 may be omitted, and the base of the transistor Q21 is directly connected to the transmitting terminal Tx through the resistor R21, at this time, the signal output by the transmitting terminal Tx simultaneously controls whether the power unit 212 operates, specifically, when the transmitting terminal Tx outputs the third signal at a high level, the transistor Q21 is turned off, and when the transmitting terminal Tx outputs the third signal at a low level, the transistor Q21 is turned on.
In the first embodiment of the present invention, when the third signal is at a high level, the transistor Q1 is turned off, and the voltage of the low-level signal received at the input/output pin IO of the control center 200 is provided by the power supply unit 12 and the modulation unit 14. In the second embodiment of the present invention, when the third signal is at a high level, the transistor Q21 turns off, and the voltage of the low-level signal received at the input/output pin IO of the control center 400 is only provided by the modulation unit 214, so that the voltage of the low-level signal received at the input/output pin IO of the control center 400 is reduced.
For example, in the first embodiment of the present invention, when the first signal is at a high level, the voltage of the low level signal received by the input/output pin IO of the control center 200 is:
V＝VD2+(IIO+IQ1)R5+VQ2
wherein V is a voltage of a low level signal received by the input/output pin IO of the control center 200, and VD2Is the voltage across the diode D2, the VQ2Is the voltage between the collector and emitter of transistor Q2, IIOFor the input/output pin IO of the control center 200 to output current, IQ1Is the output current, R, of the power supply unit 125Is the resistance of the resistor R5.
Assume that the input/output pin IO of the control center 200 outputs a current IIO350uA, the output current I of the power supply unit 12Q13mA, resistance R of the resistor R55300ohm, namely, the voltage V of the low level signal received by the input/output pin IO of the control center 200 is about 1.5V.
Correspondingly, in the second embodiment of the present invention, when the third signal is at a high level, Q21 of the transistor is turned off, so that the voltage of the low-level signal received by the input/output pin IO of the control center 400 is:
V2＝VD22+IIO2R25+VQ22
wherein, V2Is the voltage, V, of a low level signal received by an input/output pin IO of the control center 200D22Is the voltage across the diode D22, the VQ22Is the voltage between the collector and emitter of transistor Q22, IIO2For the input/output pin IO output current, R of the control center 40025Is the resistance of the resistor R25.
Under the same condition, the voltage V of the low level signal received by the input/output pin IO of the control center 4002Less than 0.8V.
The concepts described herein may be embodied in other forms without departing from the spirit or characteristics thereof. The particular embodiments disclosed should be considered illustrative rather than limiting. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. Any changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
Claims (24)
1. A single-wire bidirectional communication circuit for connecting with a control center (200,400) for real-time bidirectional data exchange, the control center (200,400) including an input/output pin (IO), the single-wire bidirectional communication circuit including an output module (10,210) and an input module (30,230), the output module (10,210) and the input module (30,230) both being connected with the input/output pin (IO) of the control center (200,400), the output module (10,210) being connected with the input/output pin (IO) of the control center (200,400) for sending a first signal to the control center (200,400), the input module (30,230) being connected with the input/output pin (IO) of the control center (200,400) for receiving a second signal from the control center (200,400), the output module (10,210) including a power supply unit (12,212), a modulation unit (14,214), A first diode (D1, D21) and a second diode (D2, D22), wherein the power supply unit (12,212) is used for providing a power supply signal to the modulation unit (14,214), the modulation unit (14,214) is used for converting the signal and outputting the signal to the control center (200,400), the anode of the first diode (D1, D21) is connected with the power supply unit (12,212), the cathode of the first diode (D1, D21) is connected with the input/output pin (IO) of the control center (200,400), the cathode of the second diode (D2, D22) is connected with the modulation unit (14,214), and the anode of the second diode (D2, D22) is connected with the input/output pin (IO) of the control center (200, 400).
2. The single-wire bidirectional communication circuit according to claim 1, wherein the output module (210) further comprises a control unit (213), and the control unit (213) is connected between the power supply unit (212) and the modulation unit (214) for receiving a signal from the modulation unit (214) to control the power supply unit (212) to operate.
3. The single-wire two-way communication circuit according to claim 1, wherein the power supply unit (12) comprises a first electronic switch (Q1), a first and a second resistor (R1R2), the control terminal of the first electronic switch (Q1) is connected to ground through the first resistor (R1), the first terminal of the first electronic switch (Q1) is connected to the anode of the first diode (D1), and the second terminal of the first electronic switch (Q1) is connected to a first power supply (Vcc) through the second resistor (R2); when the control terminal of the first electronic switch (Q1) receives a high level signal, the first terminal and the second terminal of the first electronic switch (Q1) are disconnected, and when the control terminal of the first electronic switch (Q1) receives a low level signal, the first terminal and the second terminal of the first electronic switch (Q1) are connected.
4. The single-wire bidirectional communication circuit according to claim 1, wherein the power supply unit (212) comprises a first electronic switch (Q21), a first and a second resistor (R21R22), a control terminal of the first electronic switch (Q21) is connected to the modulation unit (214) through the first resistor (R21), a first terminal of the first electronic switch (Q21) is connected to the anode of the first diode (D21), a second terminal of the first electronic switch (Q21) is connected to a first power supply (V1) through the second resistor (R22); when the modulation unit (214) outputs a high level signal, the first terminal and the second terminal of the first electronic switch (Q21) are disconnected, and when the modulation unit (214) outputs a low level signal, the first terminal and the second terminal of the first electronic switch (Q21) are connected.
5. The single-wire bidirectional communication circuit according to claim 2, wherein the power supply unit (212) comprises a first electronic switch (Q21), a first and a second resistor (R21R22), a control terminal of the first electronic switch (Q21) is connected to the control unit (213) through the first resistor (R21), a first terminal of the first electronic switch (Q21) is connected to the anode of the first diode (D21), a second terminal of the first electronic switch (Q21) is connected to a first power supply (V1) through the second resistor (R22); when the modulation unit (214) outputs a high level signal, the first end and the second end of the first electronic switch (Q21) are disconnected, and when the modulation unit (214) outputs a low level signal, the first end and the second end of the first electronic switch are connected.
6. The single-wire bidirectional communication circuit according to any of claims 3 to 5, wherein the power supply unit (12,212) further comprises a third resistor (R3, R23) and a third diode (D3, D23), wherein the anode of the third diode (D3, D23) is connected to the first power supply (Vcc, V1) through the third resistor (R3, R23), and the cathode of the third diode (D3, D23) is connected to the control terminal of the first electronic switch (Q1, Q21).
7. A single-wire two-way communication circuit according to any of claims 3 to 5, wherein the first electronic switch (Q1, Q21) is a PNP type triode.
8. The single-wire bidirectional communication circuit according to claim 1, wherein the modulation unit (14,214) comprises a second electronic switch (Q2, Q22), a fourth and fifth resistor (R4R5, R24R25), a control terminal of the second electronic switch (Q2, Q22) is connected to a transmitting terminal (TX, TX2) through the fourth resistor (R4, R24), a first terminal of the second electronic switch (Q2, Q22) is connected to a cathode of the second diode (D2, D22), and a second terminal of the second electronic switch (Q2, Q22) is grounded through the fifth resistor (R5, R25); when the control terminal of the second electronic switch (Q2, Q22) receives a low level signal, the first terminal and the second terminal of the second electronic switch (Q2, Q22) are disconnected, and when the control terminal of the second electronic switch (Q2, Q22) receives a high level signal, the first terminal and the second terminal of the second electronic switch (Q2, Q22) are connected; the transmitting end (TX, TX2) is used for transmitting the first signal.
9. The single-wire bidirectional communication circuit according to claim 4, wherein the modulation unit (214) comprises a second electronic switch (Q22), a fourth and a fifth resistor (R24R25), a control terminal of the second electronic switch (Q22) is connected to a transmitting terminal (TX2) through the fourth resistor (R24), the transmitting terminal (TX2) is further connected to the power supply unit (212), a first terminal of the second electronic switch (Q22) is connected to a cathode of the second diode (D22), and a second terminal of the second electronic switch (Q22) is connected to the ground (R25) through the fifth resistor; when the control terminal of the second electronic switch (Q22) receives a low level signal, the first terminal and the second terminal of the second electronic switch (Q22) are disconnected, and when the control terminal of the second electronic switch (Q22) receives a high level signal, the first terminal and the second terminal of the second electronic switch (Q22) are connected; the transmitting end (TX2) is used for transmitting the first signal.
10. The single-wire bidirectional communication circuit according to claim 5, wherein the modulation unit (214) comprises a second electronic switch (Q22), a fourth and a fifth resistor (R24R25), a control terminal of the second electronic switch (Q22) is connected to a transmitting terminal (TX2) through the fourth resistor (R24), the transmitting terminal (TX2) is further connected to the control unit (213), a first terminal of the second electronic switch (Q22) is connected to the cathode of the second diode (D22), and a second terminal of the second electronic switch (Q22) is grounded through the fifth resistor (R25); when the control terminal of the second electronic switch (Q22) receives a low level signal, the first terminal and the second terminal of the second electronic switch (Q22) are disconnected, and when the control terminal of the second electronic switch (Q22) receives a high level signal, the first terminal and the second terminal of the second electronic switch (Q22) are connected; the transmitting end (TX2) is used for transmitting the first signal.
11. The single-wire bidirectional communication circuit according to any of claims 8 to 10, wherein the modulating unit (14,214) further comprises a sixth resistor (R6, R26) and a fourth diode (D4, D24), an anode of the fourth diode (D4, D24) is connected to the control terminal of the second electronic switch (Q2, Q22), and a cathode of the fourth diode (D4, D24) is grounded through the sixth resistor (R6, R26).
12. A single-wire two-way communication circuit according to any of claims 8 to 10, wherein the second electronic switch (Q2, Q22) is an NPN transistor.
13. The single-wire bidirectional communication circuit according to claim 1, wherein the input module (30,230) includes a seventh resistor (R7, R27) and a zener diode (D5, D25), the input/output pin (IO) of the control center (200,400) is connected to a receiving terminal (RX, RX2) through the seventh resistor (R7, R27), the cathode of the zener diode (D5, D25) is connected to the receiving terminal (RX), and the anode of the zener diode (D5, D25) is grounded; the receiving end (RX, RX2) is configured to receive the second signal.
14. The single wire bidirectional communication circuit of claim 13, wherein the input module (30,230) further comprises a filter unit (32,232), the filter unit (32,232) being connected in parallel with the zener diode (D5, D25), the filter unit (32,232) comprising an eighth resistor (R8, R28) and a capacitor (C, C2) in parallel.
15. The single-wire bidirectional communication circuit according to claim 2, wherein the control unit (213) comprises a third electronic switch (Q23) and a ninth resistor (R29), a control terminal of the third electronic switch (Q23) is connected to a second power source (V2) through the ninth resistor (R29), a first terminal of the third electronic switch (Q23) is connected to the power source unit (212), and a second terminal of the third electronic switch (Q23) is connected to the modulation unit (214); when the control terminal of the third electronic switch (Q23) receives a low level signal, the first terminal and the second terminal of the third electronic switch (Q23) are disconnected, and when the control terminal of the third electronic switch (Q23) receives a high level signal, the first terminal and the second terminal of the third electronic switch (Q23) are connected.
16. The single-wire two-way communication circuit according to claim 15, wherein the third electronic switch (Q23) is an NPN transistor.
17. A single-wire bidirectional communication circuit for connection with a control center (200,400) for real-time bidirectional exchange of data, the control center (200,400) comprising an input-output pin (IO), the single-wire bidirectional communication circuit comprising an output module (10,210) and an input module (30,230), the output module (10,210) and the input module (30,230) each being connected with the input-output pin (IO) of the control center (200,400), the output module (10,210) comprising a power supply unit (12,212), a modulation unit (14,214), a first protection unit (D1, D21) and a second protection unit (D2, D22) for providing a power supply signal to the modulation unit (14,214) when the output module (10,210) is connected with the input-output pin (IO) of the control center (200,400), the modulation unit (14,214) is used for converting signals and outputting the signals to the control center (200,400), the first protection unit (D1, D21) is connected between the power supply unit (12,212) and an input/output pin (IO) of the control center (200,400) to prevent reverse current from damaging the power supply unit (12,212), and the second protection unit (D2, D22) is connected between the modulation unit (14,214) and the input/output pin (IO) of the control center (200,400) to prevent reverse current from damaging the modulation unit (14, 214); the input module (30,230) comprises an input resistor (R7, R27) and a zener diode (D5, D25), an input/output pin (IO) of the control center (200,400) is connected with a receiving terminal (RX, RX2) through the input resistor (R7, R27), a cathode of the zener diode (D5, D25) is connected with the receiving terminal (RX, RX2), an anode of the zener diode (D5, D25) is grounded, and the receiving terminal (RX, RX2) is used for receiving a second signal from the control center (200, 400).
18. The single-wire bidirectional communication circuit according to claim 17, wherein the first protection unit comprises a first diode (D1, D21), an anode of the first diode (D1, D21) is connected to the power supply unit (12,212), and a cathode of the first diode (D1, D21) is connected to the input/output pin (IO) of the control center (200).
19. The single-wire bidirectional communication circuit according to claim 17, wherein the second protection unit comprises a second diode (D2, D22), a cathode of the second diode (D2, D22) is connected to the modulation unit (14,214), and an anode of the second diode (D2, D22) is connected to the input/output pin (IO) of the control center (200).
20. The single-wire bidirectional communication circuit according to claim 17, wherein the output module (210) further comprises a control unit (213), the control unit (213) is connected between the power supply unit (212) and the modulation unit (214) for receiving the signal (214) from the modulation unit to control the operation of the power supply unit (212).
21. The single-wire bidirectional communication circuit according to claim 20, wherein said power supply unit (212) comprises a first electronic switch (Q21), a first resistor (R21R22), a control terminal of said first electronic switch (Q21) is connected to said control unit (213) through a first resistor (R21), a first terminal of said first electronic switch (Q21) is connected to said input/output pin of said control center through a first diode (D21), a second terminal of said first electronic switch (Q21) is connected to a first power supply (V1) through said second resistor (R22); when the modulation unit (214) outputs a high level signal, the first terminal and the second terminal of the first electronic switch (Q21) are disconnected, when the modulation unit (214) outputs a low level signal, the first terminal and the second terminal of the first electronic switch (Q21) are connected, the power supply unit (212) further includes a third resistor (R23) and a third diode (D23), the anode of the third diode (D23) is connected to the first power supply (V1) through the third resistor (R23), the cathode of the third diode (D23) is connected to the control terminal of the first electronic switch (Q21), and the first electronic switch (Q21) is a PNP type triode.
22. The single-wire bidirectional communication circuit according to claim 20, wherein the modulation unit (214) comprises a second electronic switch (Q22), a fourth resistor (R24R25), a fifth resistor (R24R25), a control terminal of the second electronic switch (Q22) is connected to a transmitting terminal (TX2) through the fourth resistor (R24), the transmitting terminal (TX2) is further connected to the control unit (213), a first terminal of the second electronic switch (Q22) is connected to the input/output pin of the control center through a second diode (D22), and a second terminal of the second electronic switch (Q22) is grounded through the fifth resistor (R25); when the control terminal of the second electronic switch (Q22) receives a low level signal, the first terminal and the second terminal of the second electronic switch (Q22) are disconnected, and when the control terminal of the second electronic switch (Q22) receives a high level signal, the first terminal and the second terminal of the second electronic switch (Q22) are connected; the transmitting terminal (TX2) is configured to transmit the first signal, the modulation unit (214) further includes a sixth resistor (R26) and a fourth diode (D24), an anode of the fourth diode (D24) is connected to the control terminal of the second electronic switch (Q22), a cathode of the fourth diode (D24) is grounded through the sixth resistor (R26), and the second electronic switch (Q22) is an NPN-type triode.
23. The single-wire bidirectional communication circuit according to claim 17, wherein the input module (230) further comprises a filter unit (232), the filter unit (232) being connected in parallel with the zener diode (D25), the filter unit (232) comprising an eighth resistor (R28) and a capacitor (C2) connected in parallel.
24. The single-wire bidirectional communication circuit according to claim 20, wherein the control unit (213) comprises a third electronic switch (Q23) and a ninth resistor (R29), a control terminal of the third electronic switch (Q23) is connected to a second power source (V2) through the ninth resistor (R29), a first terminal of the third electronic switch (Q23) is connected to the power source unit (212), and a second terminal of the third electronic switch (Q23) is connected to the modulation unit (213); when the control terminal of the third electronic switch (Q23) receives a low level signal, the first terminal and the second terminal of the third electronic switch (Q23) are disconnected, and when the control terminal of the third electronic switch (Q23) receives a high level signal, the first terminal and the second terminal of the third electronic switch (Q23) are connected, and the third electronic switch (Q23) is an NPN-type triode.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610130662.XA CN107168901B (en) | 2016-03-08 | 2016-03-08 | Single-wire bidirectional communication circuit |
| DE102017104820.0A DE102017104820A1 (en) | 2016-03-08 | 2017-03-08 | Bidirectional single-wire communication circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610130662.XA CN107168901B (en) | 2016-03-08 | 2016-03-08 | Single-wire bidirectional communication circuit |
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| CN107168901A CN107168901A (en) | 2017-09-15 |
| CN107168901B true CN107168901B (en) | 2021-06-25 |
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| CN201610130662.XA Active CN107168901B (en) | 2016-03-08 | 2016-03-08 | Single-wire bidirectional communication circuit |
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| CN (1) | CN107168901B (en) |
| DE (1) | DE102017104820A1 (en) |
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| CN107482605A (en) * | 2017-09-30 | 2017-12-15 | 广西玉柴机器股份有限公司 | A kind of anti-over-pressed K line communication devices |
| CN109960180A (en) * | 2017-12-22 | 2019-07-02 | 泰科电子(上海)有限公司 | The electronic building brick and sensor of programmable study |
| DE102018127036B4 (en) * | 2018-10-30 | 2024-01-04 | Rheinmetall Waffe Munition Gmbh | IGNITION UNIT AND AMMUNITION |
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| CN109726160B (en) * | 2018-12-20 | 2023-05-09 | 苏州路之遥科技股份有限公司 | Single-bus communication signal relay circuit with monitoring function |
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| CN113747627A (en) * | 2021-11-08 | 2021-12-03 | 深圳合芯谷微电子有限公司 | Method and system for rapid communication of series LED lamp beads |
| CN114780476B (en) * | 2022-04-15 | 2024-03-22 | 北京经纬恒润科技股份有限公司 | SPI time-sharing multiplexing circuit supporting multiple masters and multiple slaves |
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| DE102017104820A1 (en) | 2017-09-14 |
| CN107168901A (en) | 2017-09-15 |
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