CN109450762B - Single-bus communication signal isolation circuit with monitoring function - Google Patents
Single-bus communication signal isolation circuit with monitoring function Download PDFInfo
- Publication number
- CN109450762B CN109450762B CN201811590816.9A CN201811590816A CN109450762B CN 109450762 B CN109450762 B CN 109450762B CN 201811590816 A CN201811590816 A CN 201811590816A CN 109450762 B CN109450762 B CN 109450762B
- Authority
- CN
- China
- Prior art keywords
- resistor
- monitoring
- optocoupler
- electrode
- optical coupler
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- 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
- H04L12/40013—Details regarding a bus controller
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/06—Receivers
- H04B1/10—Means associated with receiver for limiting or suppressing noise or interference
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Monitoring And Testing Of Transmission In General (AREA)
- Arrangements For Transmission Of Measured Signals (AREA)
Abstract
The invention discloses a single bus communication signal isolation circuit with a monitoring function, wherein a control end of a first optical coupler is connected with a host interface end, a collector electrode of the first optical coupler is connected with a slave interface end, and an emitter electrode of the first optical coupler is connected with a ground wire at the slave interface end; the control end of the second optical coupler is connected with the slave interface end, the collector electrode of the second optical coupler is connected with the host interface end, and the emitter electrode of the second optical coupler is connected with the ground wire at the host interface end; the first monitoring unit is connected to the collector electrode and the emitter electrode of the first optical coupler and is used for monitoring electric signals on the collector electrode and the emitter electrode of the first optical coupler; and the second monitoring unit is connected with the collector electrode and the emitter electrode of the second optical coupler and is used for monitoring electric signals on the collector electrode and the emitter electrode of the second optical coupler. The invention solves the technical problem that signal transmission cannot be effectively monitored in the single bus communication process.
Description
Technical Field
The invention relates to the technical field of communication, in particular to a single bus communication signal isolation circuit with a monitoring function.
Background
The serial buses for data transmission between the microcomputer and the peripheral devices commonly used at present mainly include an I2C bus, an SPI bus and an SCI bus. In which the I2C bus communicates in a synchronous serial 2-wire manner (one clock wire, one data wire), the SPI bus communicates in a synchronous serial 3-wire manner (one clock wire, one data input wire, one data output wire), and the SCI bus communicates in an asynchronous manner (one data input wire, one data output wire). These buses require at least two or more signal lines. In recent years, a unique single Bus (1-Wire Bus) technology has been proposed. The technology is different from the bus, and adopts a single signal line, so that the clock can be transmitted, the data can be transmitted, and the data transmission is bidirectional, so that the single bus technology has the advantages of simple circuit, low hardware cost, low cost, convenience in bus expansion and maintenance and the like.
A single bus is suitable for a single host system and is capable of controlling one or more slave devices. The master may be a microcontroller and the slaves may be single bus devices, with data exchange between them via only one signal line. When only one slave device exists, the system can operate as a single-node system; when there are multiple slaves, the system operates as a multi-node system.
However, the signal of the master terminal and the signal of the slave terminal are mutually interfered in the single bus communication mode at present, so that the monitoring signal is also interfered, and the signal transmission process cannot be effectively monitored.
Disclosure of Invention
It is an object of the present invention to solve at least the above problems and to provide at least the advantages to be described later.
The invention aims to provide a single bus communication signal isolation circuit with a monitoring function, wherein a photoelectric isolated signal monitoring unit is arranged on a communication line of a host and a slave to monitor a signal transmission process, and meanwhile, the host and the slave are effectively isolated to form a mutually independent power supply system and a mutually independent grounding system by arranging isolation units on the host and the slave respectively, so that the interference of the host and the slave in information interaction is eliminated, the accuracy of signal transmission is improved, and the technical problem that the signal transmission cannot be effectively monitored in the single bus communication process is solved.
To achieve these objects and other advantages and in accordance with the purpose of the invention, there is provided a single bus communication signal isolation circuit having a monitoring function, comprising:
the control end of the first optical coupler is connected with the host interface end, the collector electrode of the first optical coupler is connected with the slave interface end, and the emitter electrode of the first optical coupler is connected with the ground wire at the slave interface end;
The control end of the second optical coupler is connected with the slave interface end, the collector electrode of the second optical coupler is connected with the host interface end, and the emitter electrode of the second optical coupler is connected with the ground wire at the host interface end;
The first monitoring unit is connected to the collector electrode and the emitter electrode of the first optical coupler and is used for monitoring electric signals on the collector electrode and the emitter electrode of the first optical coupler;
And the second monitoring unit is connected with the collector electrode and the emitter electrode of the second optical coupler and is used for monitoring electric signals on the collector electrode and the emitter electrode of the second optical coupler.
Preferably, the host interface end is provided with a first comparing unit, and the first comparing unit includes:
the cathode of the first diode is connected with the host interface end, and the host interface end is also connected with a first pull-up resistor;
the non-inverting input end of the first comparator is connected with the anode of the first diode;
and the first end of the first resistor is connected with the power supply end, and the second end of the first resistor is connected with the non-inverting input end of the first comparator.
Preferably, the light emitting diode cathode of the first optocoupler is connected with the output end of the first comparator, the light emitting diode cathode of the first optocoupler is connected to the power end through a second resistor, and the light emitting diode anode of the first optocoupler is connected to the power end through a third resistor.
Preferably, the apparatus further includes a first reference signal generating unit including:
the input end of the first buffer is connected with the collector electrode of the second optical coupler;
The first end of the fourth resistor is connected with the power end, and the second end of the fourth resistor is connected with the input end of the first buffer;
the first voltage dividing circuit comprises a fifth resistor and a sixth resistor which are arranged in series, wherein the input end of the first voltage dividing circuit is connected with the output end of the first buffer, and the output end of the first voltage dividing circuit is connected with the inverting input end of the first comparator.
Preferably, the slave interface end is provided with a second comparing unit, and the second comparing unit includes:
the cathode of the second diode is connected with the slave interface end, and the slave interface end is also connected with a second pull-up resistor;
The non-inverting input end of the second comparator is connected with the anode of the second diode;
And the first end of the seventh resistor is connected with the power supply end, and the second end of the seventh resistor is connected with the non-inverting input end of the second comparator.
Preferably, the light emitting diode cathode of the second optocoupler is connected to the output end of the second comparator, the light emitting diode cathode of the second optocoupler is connected to the power supply end through an eighth resistor, and the light emitting diode anode of the second optocoupler is connected to the power supply end through a ninth resistor.
Preferably, the apparatus further comprises a second reference signal generating unit including:
The input end of the second buffer is connected with the collector electrode of the first optical coupler;
A tenth resistor, the first end of which is connected with the power end, and the second end of which is connected with the input end of the second buffer;
The second voltage dividing circuit comprises an eleventh resistor and a twelfth resistor which are arranged in series, the input end of the second voltage dividing circuit is connected with the output end of the second buffer, and the output end of the second voltage dividing circuit is connected with the inverting input end of the second comparator.
Preferably, the device further comprises a first driving unit, wherein the first driving unit comprises a first field effect tube and a first NOT gate, the first field effect tube is an N-type field effect tube, a source electrode of the first field effect tube is connected with the host interface end, a drain electrode of the first field effect tube is grounded, a grid electrode of the first field effect tube is connected with an output end of the first NOT gate, and an input end of the first NOT gate is connected with a collector electrode of the second optocoupler;
The second driving unit comprises a second field effect tube and a second NOT gate, the second field effect tube is an N-type field effect tube, a source electrode of the second field effect tube is connected with the slave interface end, a drain electrode of the second field effect tube is grounded, a grid electrode of the second field effect tube is connected with an output end of the second NOT gate, and an input end of the second NOT gate is connected with a collector electrode of the first optocoupler.
Preferably, the first monitoring unit includes:
the cathode of the third diode is connected with the collector electrode of the first optical coupler;
The base of the first controllable triode is connected with the anode of the third diode through a thirteenth resistor, the emitting electrode of the first controllable triode is connected with a first monitoring power supply end, the collecting electrode of the first controllable triode is connected to the emitting electrode of the first optocoupler through a fourteenth resistor, and the collecting electrode of the first controllable triode is connected to the first monitoring end.
Preferably, the second monitoring unit includes:
The cathode of the fourth diode is connected with the collector electrode of the second optocoupler;
the base electrode of the second controllable triode is connected with the anode of the fourth diode through a fifteenth resistor, the emitter electrode of the second controllable triode is connected with a second monitoring power supply end, the collector electrode of the second controllable triode is connected with the anode of the light-emitting diode of the third optocoupler, and the cathode of the light-emitting diode of the third optocoupler is connected to the emitter electrode of the second optocoupler through a sixteenth resistor;
The collector electrode of the third optocoupler is connected to the second monitoring end, the second monitoring end is connected to the first monitoring power end through a seventeenth resistor, the emitter electrode of the third optocoupler is connected to the first monitoring ground wire, the second end of the fourteenth resistor is connected to the first monitoring ground wire, and the second end of the sixteenth resistor is connected to the second monitoring ground wire.
Compared with the prior art, the invention has the beneficial effects that:
1. The monitoring units are arranged on the signal transmission lines of the host end and the slave end, monitor data transmission and feed back the data transmission to the signal receiving and transmitting end so as to perform feedback control better;
2. the two signal monitoring units are used for signal isolation, so that mutual interference on the signal monitoring ends is eliminated, and the accuracy and reliability of signal monitoring are improved;
3. The optical coupling isolation is respectively arranged at the host end and the slave end, so that the host and the slave are isolated into a mutually independent power supply system and a grounding system, and the influence of signal interference between the host and the slave is eliminated;
4. The signal transmission error rate is reduced, and the reliability of single bus signal transmission is improved;
5. The stability of the signal in the transmission process is improved by the change reference of the reference signal generating unit.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.
Drawings
Fig. 1 is a circuit diagram of the present invention.
Detailed Description
The present invention will be described in further detail below with reference to the drawings so that those skilled in the art can practice the invention by referring to the description.
As shown in fig. 1, the invention provides a single bus communication signal isolation circuit with a monitoring function, which comprises a master transceiver circuit and a slave transceiver circuit, wherein the master transceiver circuit comprises a first pull-up resistor Rup1, a first comparison unit, a first optocoupler U3 and a first reference signal generation unit. The slave transceiver circuit comprises a second pull-up resistor Rup2, a second comparison unit, a second optocoupler U6 and a second reference signal generating unit.
In order to realize electrical isolation between the host transceiver circuit and the slave transceiver circuit, eliminate signal interference between the host transceiver circuit and the slave transceiver circuit, and improve the accuracy and reliability of communication between the host transceiver circuit and the slave transceiver circuit, the technical scheme of the invention is provided.
The first pull-up resistor Rup1 is connected to the host interface terminal SBUS1, and in a normal state, the voltage of the host interface terminal SBUS1 is kept at a high level through the first pull-up resistor Rup 1.
The first comparing unit is connected between the host interface terminal SBUS1 and the first optocoupler U3, and specifically includes: the device comprises a first diode D1, a first comparator OP1 and a first resistor R1, wherein the cathode of the first diode D1 is connected with a host interface end SBUS1, the non-inverting input end of the first comparator OP1 is connected with the anode of the first diode D1, and the first diode D1 is used for avoiding interference of a receiving signal of a host to a first comparison unit. An inverting input terminal of the first comparator OP1 is connected to an output terminal of the first reference signal generating unit. The first end of the first resistor R1 is connected to the power supply end Vcc, and the second end of the first resistor R1 is connected to the non-inverting input end of the first comparator OP1, and in a normal state, a high level signal is provided to the non-inverting input end of the first comparator OP 1.
The power supply terminal Vcc of the master interface terminal SBUS1 is isolated from the power supply terminal Vdd of the slave interface terminal SBUS2, and the voltages of the power supply terminals Vcc of the master interface terminal SBUS1 are consistent, and the voltages of the power supply terminals Vdd of the slave interface terminal SBUS2 are consistent.
Specifically, in this embodiment, the power terminals Vcc of the master terminal and the power terminals Vdd of the slave terminal are isolated from each other, the voltages of Vcc and Vdd may be set to 5V, and the resistances of the resistors may be equal.
The control end of the first optocoupler U3 is connected to the output end of the first comparing unit, specifically, the light emitting diode cathode of the first optocoupler U3 is connected to the output end of the first comparator OP1, the light emitting diode cathode of the first optocoupler U3 is connected to the power supply end Vcc through a second resistor R2, the light emitting diode anode of the first optocoupler U3 is connected to the power supply end Vcc through a third resistor R3, the first comparator OP1 outputs a low level, and the light emitting diode of the first optocoupler U3 emits light.
The input end of the first reference signal generating unit is connected with the collector electrode of the second optocoupler U6, and the inverting input end of the first comparator OP1 is connected with the output end of the first reference signal generating unit. Specifically, the first reference signal generating unit includes: the input end of the first buffer U1 is connected with the collector electrode of the second optocoupler U6; the first end of the fourth resistor R4 is connected with the power end Vcc, and the second end of the fourth resistor R4 is connected with the input end of the first buffer U1; the first voltage dividing circuit comprises a fifth resistor R5 and a sixth resistor R6 which are arranged in series, wherein a first end of the fifth resistor R5 is connected with the output end of the first buffer U1, and a second end of the sixth resistor R6 is grounded. The common terminal of the fifth resistor R5 and the sixth resistor R6 is connected to the inverting input terminal of the first comparator OP 1.
The first driving unit comprises a first field effect tube Q1 and a first NOT gate U2, the first field effect tube Q1 is an N-type field effect tube, the driving capability of the N-type field effect tube is stronger, and the signal transmission distance and accuracy are improved. The source electrode of the first field effect transistor Q1 is connected with the host interface terminal SBUS1, the drain electrode is grounded, the gate electrode of the first field effect transistor Q1 is connected with the output end of the first not gate U2, and the input end of the first not gate U2 is connected with the collector electrode of the second optocoupler U6.
The structure of the slave transceiver circuit is consistent with that of the master transceiver circuit, and the slave transceiver circuit and the master transceiver circuit are arranged in a staggered and symmetrical way. Specifically, the second pull-up resistor Rup2 is connected with the slave interface end SBUS2, the output end of the first optical coupler U3 is connected with the slave interface end SBUS2, and signals sent by the host are compared and shaped in sequence and then are transmitted to the slave interface end SBUS2.
The non-inverting input end of the second comparison unit is connected with the slave interface end SBUS2, and the inverting input end of the second comparison unit is connected with the output end of the first reference signal generation unit. Specifically, the second comparing unit includes: a second diode D2, a second comparator OP2 and a seventh resistor R7, wherein the cathode of the second diode D2 is connected with the slave interface terminal SBUS 2; the non-inverting input end of the second comparator OP2 is connected with the anode of the second diode D2, and the inverting input end of the second comparator OP2 is connected with the output end of the second reference signal generating unit.
A first end of the seventh resistor R7 is connected to the power supply terminal Vdd, and a second end of the seventh resistor R7 is connected to the non-inverting input terminal of the second comparator OP 2.
The control end of the second optocoupler U6 is connected to the output end of the second comparing unit, specifically, the light emitting diode cathode of the second optocoupler U6 is connected to the output end of the second comparator OP2, the light emitting diode cathode of the second optocoupler U6 is connected to the power supply end Vdd through an eighth resistor R8, and the light emitting diode anode of the second optocoupler U6 is connected to the power supply end Vdd through a ninth resistor R9. The second comparator OP2 outputs a low level, and the light emitting diode of the second optocoupler U6 emits light.
The emitter of the first optocoupler U3 is connected to the ground at the slave interface SBUS2, and the emitter of the second optocoupler U6 is connected to the ground at the host interface SBUS1, so that the emitter and collector of the first optocoupler U3 use the system voltage of the slave interface SBUS2, and the emitter and collector of the second optocoupler U6 use the system voltage of the host interface SBUS 1. Thereby, the system voltage of the master interface terminal SBUS1 and the system voltage of the slave interface terminal SBUS2 are isolated through the first optical coupler U3 and the second optical coupler U6.
The input end of the second reference signal generating unit is connected with the collector electrode of the first optical coupler U3, and the output end of the second reference signal generating unit is connected with the inverting input end of the second comparator OP 2. Specifically, the second reference signal generating unit includes: the input end of the second buffer U4 is connected with the collector electrode of the first optocoupler U3; a first end of a tenth resistor R10 is connected to the power supply terminal Vdd, and a second end of the tenth resistor R10 is connected to the input terminal of the second buffer U4; the second voltage dividing circuit comprises an eleventh resistor R11 and a twelfth resistor R12 which are arranged in series, a first end of the eleventh resistor R11 is connected with the output end of the second buffer U4, and a second end of the twelfth resistor R12 is grounded. The common terminal of the eleventh resistor R11 and the twelfth resistor R12 is connected to the inverting input terminal of the second comparator OP 2.
The second driving unit comprises a second field effect tube Q2 and a second NOT gate U5, the second field effect tube Q2 is an N-type field effect tube, a source electrode of the second field effect tube Q2 is connected with the slave interface end SBUS2, a drain electrode of the second field effect tube Q2 is grounded, a grid electrode of the second field effect tube Q2 is connected with an output end of the second NOT gate U5, and an input end of the second NOT gate U5 is connected with a collector electrode of the first optocoupler U3.
The working process is as follows:
when the host interface terminal SBUS1 sends out a high level signal, that is, the first pull-up resistor Rup1 pulls up the voltage to a high level, the voltage is input to the in-phase input terminal of the first comparator OP1, the first comparator OP1 outputs the high level, the first optocoupler U3 is not triggered, the first optocoupler U3 maintains the off state, under the action of the tenth resistor R10, the input terminal of the second not gate U5 inputs the high level, the control terminal of the second field effect transistor Q2 inputs the low level, and maintains the off state, and the slave interface terminal SBUS2 maintains the high level due to the voltage pull-up action of the second pull-up resistor Rup2, which is equivalent to receiving the high level signal.
Meanwhile, under the action of the tenth resistor R10, the input end of the second buffer U4 keeps high level, the inverting input end of the second comparator OP2 keeps high level, the second comparator OP2 outputs low level, the second optocoupler U6 is triggered, the second optocoupler U6 is turned on, the input end of the first buffer U1 inputs low level, that is, the input end of the first voltage dividing circuit inputs low level, the inverting input end of the first comparator OP1 inputs low level, so that the first comparator OP1 stably outputs high level signals, and finally the slave interface end SBUS2 keeps high level.
In the signal transmission process, the two optocouplers are used for photoelectric isolation, so that signal interference between a host system and a slave system is eliminated, and the signal transmission accuracy is improved. Meanwhile, a light emitting diode on the first optical coupler U3 is connected with a host end system, and a triode on the first optical coupler U3 is connected with a slave end system; correspondingly, the light emitting diode on the second optical coupler U6 is connected with the slave terminal system, and the triode on the second optical coupler U6 is connected with the host terminal system; thereby isolating the ground wires of the master end system and the slave end system.
When the host interface terminal SBUS1 sends out a low level signal, the low level signal is input to the non-inverting input terminal of the first comparator OP1, the first comparator OP1 outputs a low level, the first optocoupler U3 is triggered, the first optocoupler U3 is turned on, the input terminal of the second not gate U5 is grounded, which corresponds to inputting the low level, the control terminal of the second field effect transistor Q2 inputs the high level, the trigger is turned on, the slave interface terminal SBUS2 is grounded, and the slave interface terminal SBUS2 changes into the low level, which corresponds to receiving the low level signal.
Meanwhile, the input end of the second buffer U4 is grounded, the input end of the second buffer U4 receives a low level, the inverting input end of the second comparator OP2 receives a low level, the second comparator OP2 outputs a high level, the second optocoupler U6 is disconnected, the input end of the first buffer U1 inputs a high level, that is, the input end of the first voltage dividing circuit inputs a high level, the inverting input end of the first comparator OP1 inputs a high level, so that the first comparator OP1 stably outputs a low level signal, and finally the slave interface end SBUS2 keeps a low level.
By the above, the two systems are isolated by the two optical couplers, and meanwhile, the ground wires of the two optical couplers are isolated and connected, so that the master system and the slave system are finally isolated to form two independent receiving and transmitting systems, mutual interference is eliminated, and the reliability and accuracy of signal transmission are improved.
In the above process, the reference of the output end of the reference signal generating unit is changed to maintain the stability of signal transmission.
When the slave interface SBUS2 sends a signal and the master interface SBUS1 receives a signal, the working process is identical to the process of sending the signal from the master interface SBUS1 to the slave interface SBUS 2.
The first monitoring unit is connected to the collector and the emitter of the first optical coupler U3, and is configured to monitor the electrical signals on the collector and the emitter of the first optical coupler U3, that is, monitor the transmission signals from the host interface end to the slave interface end.
The first monitoring unit includes: the cathode of the third diode D3 is connected with the collector of the first optocoupler U3; the base electrode of the first controllable triode Q3 is connected with the anode of the third diode D3 through a thirteenth resistor R13,
The emitter of the first controllable triode Q3 is connected with a first monitoring power supply end Vp1, the collector of the first controllable triode Q3 is connected to the emitter of the first optocoupler U3 through a fourteenth resistor R14, and the collector of the first controllable triode Q3 is connected to a first monitoring end Moni1.
The second monitoring unit is connected to the collector and the emitter of the second optical coupler U6, and is configured to monitor the electrical signals on the collector and the emitter of the second optical coupler U6, that is, monitor the transmission signals from the host interface to the slave interface.
The second monitoring unit includes: a cathode of the fourth diode D4 is connected with a collector of the second optocoupler U6; the base of the second controllable triode Q4 is connected to the anode of the fourth diode D4 through a fifteenth resistor R15, the emitter of the second controllable triode Q4 is connected to the second monitoring power supply terminal Vp2, the collector of the second controllable triode Q4 is connected to the anode of the light emitting diode of the third optocoupler U7, and the cathode of the light emitting diode of the third optocoupler U7 is connected to the emitter of the second optocoupler U7 through a sixteenth resistor R16.
The collector of the third optocoupler U7 is connected to the second monitor terminal Moni2, the second monitor terminal is connected to the first monitor power terminal Vp1 through a seventeenth resistor R17, the emitter of the third optocoupler U7 is connected to the first monitor ground line Vp1_gnd, the second end of the fourteenth resistor R14 is connected to the first monitor ground line Vp1_gnd, and the second end of the sixteenth resistor R16 is connected to the second monitor ground line Vp2_gnd.
Therefore, the power supply ends adopted by the first monitoring unit and the second monitoring unit are mutually independent, the adopted ground wires are mutually independent, mutual interference between the two monitoring units is eliminated, and meanwhile, the first monitoring end Moni1 and the second monitoring end Moni2 are arranged on one side, so that monitoring and observation are facilitated.
The monitoring process is as follows:
the first controllable triode Q3 and the second controllable triode Q2 are P-type triodes, when the collector electrode of the first optocoupler U3 is high in level, the first controllable triode Q3 is disconnected, and the first monitoring end Moni1 receives low level; when the collector of the first optocoupler U3 is at a low level, the first controllable triode Q3 is turned on, and the first monitor terminal monitor 1 receives a high level.
When the collector of the second optocoupler U6 is at a high level, the second controllable triode Q4 is turned off, the third optocoupler U7 is not triggered, and the second monitoring terminal monitor 2 receives the high level. When the collector of the second optocoupler U6 is at a low level, the second controllable triode Q4 is turned on, the third optocoupler U7 is triggered, and the second monitoring terminal monitor 2 receives the low level.
The level signals on the communication line of the master-slave machine can be monitored through the two monitoring units.
In the invention, the monitoring unit is arranged on the signal transmission lines of the host end and the slave end, monitors data transmission and feeds back the data transmission to the signal receiving and transmitting end so as to perform feedback control better; meanwhile, the two signal monitoring units perform signal isolation, so that mutual interference on the signal monitoring ends is eliminated, and the accuracy and reliability of signal monitoring are improved; on the other hand, the invention isolates the master machine and the slave machine into a mutually independent power supply system and a grounding system by arranging the optical coupling isolation at the master machine end and the slave machine end respectively, so as to eliminate the influence of signal interference between the master machine and the slave machine; meanwhile, the signal transmission error rate is reduced, and the reliability of single bus signal transmission is improved. And the stability of the signal in the transmission process is improved through the change reference of the reference signal generating unit.
Although embodiments of the present invention have been disclosed above, it is not limited to the details and embodiments shown and described, it is well suited to various fields of use for which the invention would be apparent to those skilled in the art, and accordingly, the invention is not limited to the specific details and illustrations shown and described herein without departing from the general concepts defined in the claims and their equivalents.
Claims (8)
1. A single bus communication signal isolation circuit with monitoring function, comprising:
The control end of the first optical coupler is connected with the host interface end, the collector electrode of the first optical coupler is connected with the slave interface end, and the emitter electrode of the first optical coupler is connected with the ground wire at the slave interface end;
The control end of the second optical coupler is connected with the slave interface end, the collector electrode of the second optical coupler is connected with the host interface end, and the emitter electrode of the second optical coupler is connected with the ground wire at the host interface end;
The first monitoring unit is connected to the collector electrode and the emitter electrode of the first optical coupler and is used for monitoring electric signals on the collector electrode and the emitter electrode of the first optical coupler;
the second monitoring unit is connected with the collector electrode and the emitter electrode of the second optical coupler and is used for monitoring electric signals on the collector electrode and the emitter electrode of the second optical coupler;
the first monitoring unit includes:
the cathode of the third diode is connected with the collector electrode of the first optical coupler;
The base electrode of the first controllable triode is connected with the anode of the third diode through a thirteenth resistor, the emitting electrode of the first controllable triode is connected with a first monitoring power supply end, the collecting electrode of the first controllable triode is connected with the emitting electrode of the first optocoupler through a fourteenth resistor, and the collecting electrode of the first controllable triode is connected with a first monitoring end;
the second monitoring unit includes:
The cathode of the fourth diode is connected with the collector electrode of the second optocoupler;
the base electrode of the second controllable triode is connected with the anode of the fourth diode through a fifteenth resistor, the emitter electrode of the second controllable triode is connected with a second monitoring power supply end, the collector electrode of the second controllable triode is connected with the anode of the light-emitting diode of the third optocoupler, and the cathode of the light-emitting diode of the third optocoupler is connected to the emitter electrode of the second optocoupler through a sixteenth resistor;
the collector electrode of the third optical coupler is connected to the second monitoring end, the second monitoring end is connected to the first monitoring power end through a seventeenth resistor, the emitter electrode of the third optical coupler is connected to the first monitoring ground wire, the second end of the fourteenth resistor is connected to the first monitoring ground wire, and the second end of the sixteenth resistor is connected to the second monitoring ground wire;
The monitoring process of the single bus communication signal isolation circuit with the monitoring function is as follows: the first controllable triode and the second controllable triode are P-type triodes, when the high level is on the collector of the first optocoupler, the first controllable triode is disconnected, and the first monitoring terminal receives the low level; when the upper level of the first optocoupler collector is low, the first controllable triode is opened, and the first monitoring terminal receives a high level;
when the second optocoupler is at a high level on the collector electrode, the second controllable triode is disconnected, the third optocoupler is not triggered, and the second monitoring terminal receives the high level; when the collector of the second optocoupler is at a low level, the second controllable triode is turned on, the third optocoupler is triggered, and the second monitoring terminal receives the low level.
2. The single bus communication signal isolation circuit with monitoring function according to claim 1, wherein the host interface terminal is provided with a first comparing unit, the first comparing unit comprises:
the cathode of the first diode is connected with the host interface end, and the host interface end is also connected with a first pull-up resistor;
the non-inverting input end of the first comparator is connected with the anode of the first diode;
and the first end of the first resistor is connected with the power supply end, and the second end of the first resistor is connected with the non-inverting input end of the first comparator.
3. The single bus communication signal isolation circuit with monitoring function according to claim 2, wherein the led cathode of the first optocoupler is connected to the output terminal of the first comparator, the led cathode of the first optocoupler is connected to the power terminal through a second resistor, and the led anode of the first optocoupler is connected to the power terminal through a third resistor.
4. The single bus communication signal isolation circuit with monitoring function as set forth in claim 3, further comprising a first reference signal generating unit comprising:
the input end of the first buffer is connected with the collector electrode of the second optical coupler;
The first end of the fourth resistor is connected with the power end, and the second end of the fourth resistor is connected with the input end of the first buffer;
the first voltage dividing circuit comprises a fifth resistor and a sixth resistor which are arranged in series, wherein the input end of the first voltage dividing circuit is connected with the output end of the first buffer, and the output end of the first voltage dividing circuit is connected with the inverting input end of the first comparator.
5. The single bus communication signal isolation circuit with monitoring function as set forth in claim 4, wherein said slave interface is provided with a second comparing unit, said second comparing unit comprising:
the cathode of the second diode is connected with the slave interface end, and the slave interface end is also connected with a second pull-up resistor;
The non-inverting input end of the second comparator is connected with the anode of the second diode;
And the first end of the seventh resistor is connected with the power supply end, and the second end of the seventh resistor is connected with the non-inverting input end of the second comparator.
6. The single bus communication signal isolation circuit with monitoring function according to claim 5, wherein the led cathode of the second optocoupler is connected to the output terminal of the second comparator, the led cathode of the second optocoupler is connected to the power terminal through an eighth resistor, and the led anode of the second optocoupler is connected to the power terminal through a ninth resistor.
7. The single bus communication signal isolation circuit with monitoring function of claim 6, further comprising a second reference signal generating unit comprising:
The input end of the second buffer is connected with the collector electrode of the first optical coupler;
A tenth resistor, the first end of which is connected with the power end, and the second end of which is connected with the input end of the second buffer;
The second voltage dividing circuit comprises an eleventh resistor and a twelfth resistor which are arranged in series, the input end of the second voltage dividing circuit is connected with the output end of the second buffer, and the output end of the second voltage dividing circuit is connected with the inverting input end of the second comparator.
8. The single bus communication signal isolation circuit with monitoring function as set forth in claim 7, further comprising a first driving unit, wherein the first driving unit comprises a first field effect transistor and a first NOT gate, the first field effect transistor is an N-type field effect transistor, a source electrode of the first field effect transistor is connected with the host interface terminal, a drain electrode of the first field effect transistor is grounded, a gate electrode of the first field effect transistor is connected with an output terminal of the first NOT gate, and an input terminal of the first NOT gate is connected with a collector electrode of the second optocoupler;
The second driving unit comprises a second field effect tube and a second NOT gate, the second field effect tube is an N-type field effect tube, a source electrode of the second field effect tube is connected with the slave interface end, a drain electrode of the second field effect tube is grounded, a grid electrode of the second field effect tube is connected with an output end of the second NOT gate, and an input end of the second NOT gate is connected with a collector electrode of the first optocoupler.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811590816.9A CN109450762B (en) | 2018-12-20 | 2018-12-20 | Single-bus communication signal isolation circuit with monitoring function |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811590816.9A CN109450762B (en) | 2018-12-20 | 2018-12-20 | Single-bus communication signal isolation circuit with monitoring function |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109450762A CN109450762A (en) | 2019-03-08 |
| CN109450762B true CN109450762B (en) | 2024-05-10 |
Family
ID=65535447
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811590816.9A Active CN109450762B (en) | 2018-12-20 | 2018-12-20 | Single-bus communication signal isolation circuit with monitoring function |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109450762B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1674381A (en) * | 2005-03-10 | 2005-09-28 | 上海交通大学 | Under-voltage isolating monitoring circuit |
| CN101216506A (en) * | 2008-01-02 | 2008-07-09 | 江苏省电力公司无锡供电公司 | Optical coupling isolation control interface circuit structure |
| CN201118630Y (en) * | 2007-11-09 | 2008-09-17 | 深圳天行健电子有限公司 | A non-polarity two-core communication bus receiver/transmitter for photoelectrical separation |
| CN205679749U (en) * | 2016-06-06 | 2016-11-09 | 武汉奇星电子有限公司 | Power on/off observation circuit |
| CN206835082U (en) * | 2017-06-08 | 2018-01-02 | 深圳市拓普泰克电子有限公司 | Serial ports isolates communication interface circuit and electronic equipment |
| CN209250666U (en) * | 2018-12-20 | 2019-08-13 | 苏州路之遥科技股份有限公司 | A kind of monobus communication signal isolation circuit with monitoring function |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101211329B (en) * | 2006-12-26 | 2011-05-04 | 鸿富锦精密工业（深圳）有限公司 | Serial port connecting circuit |
-
2018
- 2018-12-20 CN CN201811590816.9A patent/CN109450762B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1674381A (en) * | 2005-03-10 | 2005-09-28 | 上海交通大学 | Under-voltage isolating monitoring circuit |
| CN201118630Y (en) * | 2007-11-09 | 2008-09-17 | 深圳天行健电子有限公司 | A non-polarity two-core communication bus receiver/transmitter for photoelectrical separation |
| CN101216506A (en) * | 2008-01-02 | 2008-07-09 | 江苏省电力公司无锡供电公司 | Optical coupling isolation control interface circuit structure |
| CN205679749U (en) * | 2016-06-06 | 2016-11-09 | 武汉奇星电子有限公司 | Power on/off observation circuit |
| CN206835082U (en) * | 2017-06-08 | 2018-01-02 | 深圳市拓普泰克电子有限公司 | Serial ports isolates communication interface circuit and electronic equipment |
| CN209250666U (en) * | 2018-12-20 | 2019-08-13 | 苏州路之遥科技股份有限公司 | A kind of monobus communication signal isolation circuit with monitoring function |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109450762A (en) | 2019-03-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109525475B (en) | Single bus communication signal isolation circuit | |
| CN104216855B (en) | A kind of USB turns the active isolating converters of RS 485 | |
| CN109474505B (en) | Single-bus communication signal enhancement circuit with monitoring function | |
| CN109450762B (en) | Single-bus communication signal isolation circuit with monitoring function | |
| CN109586750B (en) | A single bus communication signal enhancement circuit | |
| CN104113444A (en) | Current loop communication control and detection circuit | |
| CN209250666U (en) | A kind of monobus communication signal isolation circuit with monitoring function | |
| CN105160862A (en) | M-BUS (METER-BUS) slave communication circuit | |
| CN109726160B (en) | Single-bus communication signal relay circuit with monitoring function | |
| CN209250665U (en) | A kind of monobus communication signal isolation circuit | |
| CN209250667U (en) | A kind of monobus communication signal enhancing circuit with monitoring function | |
| CN109522260B (en) | Single-bus communication signal relay circuit | |
| CN203520392U (en) | Communication circuit for electronic exploration detonator | |
| CN111404504B (en) | RS485 bus differential signal amplifier | |
| CN216599583U (en) | Communication circuit, electronic equipment and communication system | |
| CN215809187U (en) | Current loop communication circuit and air conditioner | |
| CN201869212U (en) | Two-wire-system host computer circuit | |
| CN101290607B (en) | Chip debugging interface device | |
| CN114650192B (en) | CRPB bus system | |
| CN109921610B (en) | Extension set for realizing two-wire system bus | |
| CN209248523U (en) | A kind of monobus communication signal repeat circuit | |
| CN209046639U (en) | A kind of data transmit-receive circuit and communication instrument | |
| CN204066107U (en) | A kind of USB turns the active isolating converter of RS-485 | |
| CN218482773U (en) | Compatible circuit of power supply based on RS485 interface | |
| CN216719086U (en) | Electric energy meter communication isolation circuit, device and electric energy meter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |