CN106559106B

CN106559106B - Signal transmitter

Info

Publication number: CN106559106B
Application number: CN201710012916.2A
Authority: CN
Inventors: 陈良生
Original assignee: Shanghai Enchips Integrated Circuit Co ltd; Qingdao Topscomm Communication Co Ltd
Current assignee: Shanghai Enchips Integrated Circuit Co ltd; Qingdao Topscomm Communication Co Ltd
Priority date: 2017-01-09
Filing date: 2017-01-09
Publication date: 2022-12-09
Anticipated expiration: 2037-01-09
Also published as: CN106559106A

Abstract

A signal transmitter comprising a signal transmitting circuit, the signal transmitting circuit comprising: the digital control module is used for performing digital logic processing on the signal to be transmitted and outputting a digital control signal; and the current output module is connected with the digital control module and used for outputting a current signal matched with the characteristics of the signal to be transmitted under the control of the digital control signal output by the digital control module, and comprises a positive output end and a negative output end which are respectively connected to two ends of the primary coil of the magnetic coupler. The signal transmitter has low power consumption.

Description

Signal transmitter

Technical Field

The invention relates to the technical field of power communication, in particular to a signal transmitter.

Background

The communication is usually carried out between strong electricity and weak electricity signals, and the physical isolation is usually carried out between a strong electricity sending end and a weak electricity receiving end, so that the communication is generally realized by adopting optical coupling under the traditional communication environment needing to realize isolation, and a good electrical isolation effect is achieved through photoelectric conversion and electro-optical conversion.

Fig. 1 is a schematic diagram of a circuit module for implementing communication based on optical coupling in the prior art. The transmitting end 101 converts a current signal into an optical signal through the light emitting diode 102; the receiving end 104 receives the optical signal emitted by the light emitting diode 102 through the photodiode 103, and converts the optical signal into an electrical signal, thereby implementing signal transmission between the transmitting end 101 and the receiving end 104. However, the above method requires a high current, large power consumption, and high cost to realize the electro-optical conversion.

Therefore, a new signal transmitter is needed, which can realize low-power and low-cost signal transmission.

Disclosure of Invention

The invention aims to provide a signal transmitter, which realizes signal transmission with low power consumption and low cost.

In order to solve the above problems, the present invention provides a signal transmitter comprising: the digital control module is used for performing digital logic processing on the signal to be transmitted and outputting a digital control signal; and the current output module is connected with the digital control module and used for outputting a current signal matched with the characteristics of the signal to be transmitted under the control of the digital control signal output by the digital control module, and comprises a positive output end and a negative output end which are respectively connected to two ends of the primary coil of the magnetic coupler.

Optionally, the signal to be sent is a digital signal, and the digital control signal is used to control the flow direction of the current signal output by the current output module, so that the current signal flowing in the positive direction corresponds to the high level of the signal to be sent, and the current signal flowing in the negative direction corresponds to the low level of the signal to be sent.

Optionally, the current output module includes a first switch, a second switch, a third switch and a fourth switch that are connected in sequence, the current source is connected between the first switch and the second switch, the positive output end is located between the first switch and the fourth switch, the negative output end is located between the second switch and the third switch, and the first switch, the second switch, the third switch and the fourth switch are respectively connected to the digital control signal output end of the digital control module.

Optionally, the digital control signal output terminal includes: a first terminal connected to the third switch for outputting a first signal; a second terminal connected to the fourth switch for outputting a second signal; a first inverting terminal connected to the first switch for outputting a first inverted signal; a second inverting terminal connected to the second switch for outputting a second inverted signal; the first signal and the first reverse signal are reverse signals, and the second signal and the second reverse signal are reverse signals.

Optionally, the first signal and the second signal are two-phase non-overlapping signals.

Optionally, the first switch, the second switch, the third switch and the fourth switch respectively have a plurality of switch elements, and the digital control signal is used to sequentially turn on or off the plurality of switch elements in the first switch, the second switch, the third switch and the fourth switch.

Optionally, the current output module includes a seventh switch and an eighth switch; one end of the seventh switch is connected to the current source, and the other end of the seventh switch is connected to the negative end of the power supply; one end of the eighth switch is connected to the current source, and the other end of the eighth switch is connected to the forward output end; the negative output end is connected to the negative end of the power supply.

Optionally, the current output module includes a ninth switch and a tenth switch; one end of the ninth switch is connected to the positive end of the power supply, and the other end of the ninth switch is connected to the negative end of the power supply; one end of the tenth switch is connected to the negative output end, and the other end of the tenth switch is connected to the negative end of the power supply; the positive output end is connected to the positive power supply end.

Optionally, the signal to be sent is a digital signal, and the digital control signal is used to control the current signal output by the current output module, and corresponds to a high level of the signal to be sent when the current signal is output, and corresponds to a low level of the signal to be sent when no current signal is output; or a low level corresponding to a signal to be transmitted when a current signal is output and a high level corresponding to a signal to be transmitted when no current signal is output.

Optionally, the apparatus further includes a signal receiving circuit, where the signal receiving circuit includes: the current-voltage conversion module comprises a positive receiving end and a negative receiving end, the positive receiving end and the negative receiving end are respectively connected to two ends of a secondary coil of the magnetic coupler, and the current-voltage conversion module is used for receiving a current signal generated by the secondary coil under the induction of a primary coil of the magnetic coupler and converting the current signal into a voltage signal; and the digital processing module is connected with the current-voltage conversion module and used for processing the voltage signal output by the current-voltage conversion module and outputting a digital signal.

Optionally, the current-voltage conversion module includes a common mode end, a first resistor connected to the common mode end and the positive receiving end, and a second resistor connected to the common mode end and the negative receiving end, where a connection end of the first resistor and the positive receiving end serves as a first output end, and a connection end of the second resistor and the negative receiving end serves as a second output end.

Optionally, the digital processing module includes a comparator, the first output end is connected to the positive input end of the comparator, and the second output end is connected to the negative input end of the comparator.

Optionally, the signal receiving circuit further includes a signal filtering module connected to the digital processing module, and configured to remove an error signal output by the digital processing module.

A signal transmitter, comprising: a signal receiving circuit, the signal receiving circuit comprising: the current-voltage conversion module comprises a positive receiving end and a negative receiving end, the positive receiving end and the negative receiving end are respectively connected to two ends of a secondary coil of the magnetic coupler, and the current-voltage conversion module is used for receiving a current signal generated by the secondary coil under the induction of a primary coil of the magnetic coupler and converting the current signal into a voltage signal; and the digital processing module is connected with the current-voltage conversion module and used for processing the voltage signal output by the current-voltage conversion module and outputting a digital signal.

Optionally, the current-voltage conversion module includes a common-mode terminal, a first resistor connected to the common-mode terminal and the positive receiving terminal, and a second resistor connected to the common-mode terminal and the negative receiving terminal, where a connection end of the first resistor and the positive receiving terminal is used as a first output end, and a connection end of the second resistor and the negative receiving terminal is used as a second output end.

The signal transmitter comprises a signal sending circuit, wherein the signal sending circuit is used for converting a signal to be sent into a current signal to be sent, and the current signal is used as a carrier of the signal to be sent. The signal transmitter also comprises a signal receiving circuit which is used for receiving the current signal and converting the current signal into a digital signal to be output, thereby realizing the decoding of the current signal. The sending and receiving processes of the signals do not need large current, so that the power consumption can be reduced, and the cost is reduced.

Drawings

FIG. 1 is a schematic diagram of a circuit module for implementing communication based on optical coupling according to the prior art;

FIG. 2 is a schematic structural diagram of a signal transmitter according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a signal transmitter according to an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a signal transmitter according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a signal transmitter according to an embodiment of the present invention;

fig. 6 is a schematic diagram of sub-signals of a first signal sent by a digital control module in a signal receiving circuit of a signal transmitter according to an embodiment of the present invention;

fig. 7 is a schematic diagram of digital control signals output by a digital control module in a signal receiving circuit of a signal transmitter according to an embodiment of the present invention;

FIG. 8 is a schematic structural diagram of a signal transmitter according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of a signal transmitter according to an embodiment of the present invention.

Detailed Description

The following describes in detail a specific embodiment of the signal transmitter according to the present invention with reference to the accompanying drawings.

Fig. 2 is a schematic structural diagram of a signal transmitter according to an embodiment of the present invention.

In this embodiment, the signal transmitter includes a signal transmitting circuit 201, and the signal transmitting circuit 201 includes a digital control module 211 and a current output module 212 connected to the digital control module 211. When the signal transmitter is used as a signal transmission device, the signal transmission circuit 201 operates.

The digital control module 211 includes a signal input terminal for inputting a signal to be transmitted; the digital control module 211 is configured to perform digital logic processing on a signal to be sent, and output a digital control signal. The signal to be transmitted is a digital signal, or the signal to be transmitted is an analog signal, and analog-to-digital conversion is performed through the digital control module 211.

The current output module 212 is connected to a power supply terminal, and is configured to output a current signal that is matched with a characteristic of a signal to be transmitted under the control of a digital control signal output by the digital control module 211, and the current output module includes a positive output terminal and a negative output terminal, where the positive output terminal and the negative output terminal are respectively connected to two ends of a primary coil of the magnetic coupler 202.

The digital control module 211 outputs a corresponding control signal according to the input signal to be transmitted, and controls the current output module 212, so that the current signal characteristic output by the current output module 212 corresponds to the input signal characteristic to be transmitted. For example, when the input signal to be transmitted is a digital signal, the high level of the signal to be transmitted corresponds to the current flowing from the positive output terminal to the negative output terminal of the current output module 212, that is, the current flowing in the positive direction; the low level of the signal to be transmitted corresponds to the current flowing from the negative output terminal to the positive output terminal of the current output module 212, i.e. the current flowing in the opposite direction. The direction of the current signal corresponds to the high and low levels of the input signal to be transmitted. The signal transmission circuit 201 thus converts the signal to be transmitted into a current signal, which is coupled to the secondary coil by the primary coil of the magnetic coupler 202 and output. When the signal transmitter transmits signals, the direction of the current signals is mainly used as signal carriers, and a large current value is not needed, so that the power consumption can be reduced, and the cost can be reduced.

Fig. 3 is a schematic structural diagram of a signal transmitter according to another embodiment of the present invention.

The signal transmitter includes a signal receiving circuit 301, the signal transmitter functions as a signal receiving device, and the signal receiving circuit 301 operates. The signal receiving circuit 301 includes a current-voltage conversion module 311, and a digital processing module 312 connected to the current-voltage conversion module 311.

The current-voltage conversion module 311 includes a positive receiving end and a negative receiving end, where the positive input end and the negative input end are respectively connected to two ends of the secondary coil of the magnetic coupler 301. The current-voltage conversion module 311 is configured to receive a current signal generated by the secondary coil induced by the primary coil of the magnetic coupler 302, and convert the current signal into a voltage signal.

The digital processing module 312 is connected to the current-to-voltage conversion module 311, and configured to process the voltage signal output by the current-to-voltage conversion module 311 and output a digital signal.

The current-voltage conversion module 311 converts the received current signal into a voltage signal, and the digital processing module 312 performs analog-to-digital conversion on the voltage signal to form a digital signal, where the high and low levels of the digital signal correspond to the direction of the input current signal, so as to convert the received current signal into a digital signal and perform signal decoding. When the signal transmitter receives signals, the signals are mainly decoded through the direction of the current signals, and a large current value is not needed, so that the power consumption can be reduced, and the cost can be reduced.

Fig. 4 is a schematic structural diagram of a signal transmitter according to another embodiment of the present invention.

The signal transmitter comprises a signal sending circuit 401 and a signal receiving circuit 402 at the same time, wherein the signal sending circuit 401 is used for converting a signal to be sent into a current signal to be sent and sending the current signal, and the current direction of the current signal corresponds to the high and low levels of the signal to be sent; the signal receiving current 402 is configured to convert a received current signal into a voltage signal, perform analog-to-digital conversion on the voltage signal to form a digital signal, and decode the received signal, thereby implementing signal transmission. However, the signal transmitter can only be used as a signal transmitting device or a signal receiving device, and two signal transmitters are required to complete the signal transmitting and receiving process, wherein the signal transmitting circuit of one signal transmitter is connected to the primary coil of one magnetic coupler, the signal receiving circuit of the other signal transmitter is connected to the secondary coil of the magnetic coupler, the current signal transmitted by the signal transmitting circuit is coupled to the secondary coil through the primary coil of the magnetic coupler, and the current signal is received by the receiving circuit of the other signal transmitter, converted into a voltage and subjected to analog-to-digital conversion to form a digital signal output, thereby realizing the signal transmission and reception.

Fig. 5 is a schematic structural diagram of a signal transmitter according to another embodiment of the present invention.

In order to show the working principle of the signal transmitter more clearly, in fig. 5, there are two signal transmitters having both signal transmitting and receiving functions, which are respectively used as a signal transmitter and a signal receiver, and are connected to a magnetic coupler 530.

The signal transmitter used as a signal transmitter includes a signal transmitting circuit 511 and a signal receiving circuit 512; the signal transmitter used as the signal receiver includes a signal transmitting circuit 521 and a signal receiving circuit 522; the signal transmitting circuit 511 and the signal transmitting circuit 521 of the two signal transmitters have the same circuit configuration, and the signal receiving circuit 512 and the signal receiving circuit 522 have the same circuit configuration.

The signal transmitting circuit 511 includes a digital control module 5111, and the digital control module 5111 is configured to perform digital processing on a signal din to be transmitted, and transmit a control signal according to the characteristic information of the signal din to be transmitted. The digital control module 5111 is controlled by a clock signal, an enable signal, and a control signal.

The signal transmitting circuit 511 further includes a current output module, which includes: the constant current source Ib of the current output module is a constant current source Ib, and the current Ib can be 100 mu A-400 mu A. The current output module comprises a positive output end dp and a negative output end dn, the positive output end dp is located between the first switch K1 and the fourth switch K4, and the negative input end dn is located between the second switch K2 and the third switch K3. The power supply cathode VSS is connected between the third switch K3 and the fourth switch K4 through a current mirror circuit.

The first switch K1, the second switch K2, the third switch K3 and the fourth switch K4 are respectively connected to a digital control signal output end of the digital control module 5111. In an embodiment of the present invention, the digital control module 5111 includes a first terminal connected to the third switch K3 for outputting the first signal phil; a second end connected to the fourth switch K4 for outputting a second signal phi2; a first inverting terminal connected to the first switch K1 for outputting a first inverted signal phi1b; and a second inverting terminal connected to the second switch K2 for outputting a second inverted signal phi2b. The first signal phil, the second signal phi2, the first reverse signal philb and the second reverse signal phi2b are all digital signals, wherein the first signal phil and the first reverse signal philb are mutually reverse signals, and when the first signal phil controls the third switch K3 to be turned on, the first reverse signal philb controls the first switch K1 to be turned on; when the first signal phil controls the third switch K3 to be turned off, the first reverse signal philb controls the first switch K1 to be turned off. The second signal phi2 and the second reverse signal phi2b are mutually reverse signals, and when the second signal phi2 controls the fourth switch K4 to be turned on, the second reverse signal phi2b controls the second switch K2 to be turned on; when the second signal phi2 controls the fourth switch K4 to be turned off, the second reverse signal phi2b controls the second switch K2 to be turned off. In an embodiment of the invention, the first switch K1 and the second switch K2 are low-level conducting switches, such as PMOS transistors, and the third switch K3 and the fourth switch K4 are high-level conducting switches, such as NMOS transistors.

The digital control module 5111 adjusts the current direction in the current output module by controlling the on and off states of the first switch K1, the second switch K2, the third switch K3 and the fourth switch K4. When the digital control module 5111 controls the first switch K1 and the third switch K3 to be turned on, and the second switch K2 and the fourth switch K4 to be turned off, the current direction flows from the positive output terminal dp to the negative output terminal dn, and when the positive output terminal dp and the negative output terminal dn are connected to the primary coil 531 of the magnetic coupler 530, a current flowing in the positive direction is generated in the primary coil 531, so as to form an induced current in the secondary coil 532.

In an embodiment of the present invention, the second switch K2, the third switch K3, and the fourth switch K4 may be a single switching device, such as a transistor, a triode, a thyristor, etc.; in this embodiment, each of the first switch K1, the second switch K2, the third switch K3, and the fourth switch K4 is a switch module including a plurality of switch elements, and the first switch K1, the second switch K2, the third switch K3, or the fourth switch K4 can be completely turned on only when n switch elements in the switch module are turned on. Therefore, in this embodiment, the first signal Phi1, the first signal Phi2, the first direction signal Phi1b and the second direction signal Phi2b each include a plurality of digital signals, namely Phi1< n:0>, phi2< n:0>, phi1b < n:0> and Phi2b < n:0>, respectively controlling n +1 switching elements in the first switch K1, the second switch K2, the third switch K3 and the fourth switch K4.

In an embodiment of the present invention, in order to avoid abrupt change of the current in the primary coil 531 in the magnetic coupler 530, which may result in a large self-inductance current generated in the primary coil 531, and thus cause a large error in signal transmission, the n switching elements in the first switch K1, the second switch K2, the third switch K3, and the fourth switch K4 are turned on or off one by one. Therefore, the n signals of the first signal Phi1, the first signal Phi2, the first direction signal Phi1b and the second direction signal Phi2b are adjacent delay signals. In a specific embodiment of the present invention, the first switch K1, the second switch K2, the third switch K3, and the fourth switch K4 include 5 switch elements, for example, a first signal Phi1< n:0> for controlling the third switch K3, when the signal din to be transmitted is a square wave signal, referring to fig. 6, the schematic diagram of each sub-signal in the Phi1<4 > is shown, 5 sub-signals in the first signal Phi1<4 < 0> are respectively adjacent delay signals, the signal edges sequentially and one by one rise or fall, and each sub-signal is delayed by 1ns to 10ns from a previous sub-signal, so that the 5 switch elements in the first switch K1 are sequentially turned on or off, and the current is slowly increased or decreased, thereby avoiding a sudden change of the current in the original coil 531.

Further, in order to avoid that the states of the first switch K1 and the fourth switch K4, or the first switch K2 and the third switch K3 are the same in a short time during the switching of the switch states, which causes the current signal to flow to the power supply negative terminal VSS, the first signal Phi1 and the second signal Phi2 are two-phase non-overlapping signals, and the first direction signal Phi1b and the second direction signal Phi2b are also two-phase non-overlapping signals, please refer to fig. 6, which is a schematic diagram of the first signal Phi1, the second signal Phi2, the first inverse signal Phi1b and the second inverse signal Phi2b when the signal din to be transmitted is a square wave. The signal edges of the first signal Phi1 and the second signal Phi2 are not overlapped; the signal edges of the first direction signal Phi1b and the second direction signal Phi2b do not overlap.

The current output module further comprises a resistor R5 located between the first switch K1 and the positive output end dp, a resistor R6 located between the second switch and the negative output end dn, a resistor R8 located between the third switch K3 and the negative output end dn, and a resistor R7 located between the fourth switch K4 and the positive output end. When the current on the primary coil 531 of the magnetic coupler 530 suddenly changes, a flyback voltage is generated, and the resistors R5, R6, R7, and R8 are used to isolate the influence of the flyback voltage on the switches K1 to K4, and simultaneously, the impedance matching between the primary coil and the secondary coil of the magnetic coupler 530 is realized. The resistors R5, R6, R7, and R8 may have the same resistance value, and the resistors R5, R6, R7, and R8 may also be adjustable resistors, and are used to implement impedance matching between the signal sending circuit 511 and the magnetic coupler 530 by adjusting the resistance values of the resistors R5, R6, R7, and R8, and improve the signal transmission efficiency.

The signal transmitting circuit 511 converts a signal din to be transmitted into a current signal, couples the current signal to the secondary coil 532 through the primary coil 531 of the magnetic coupler 530, and receives the current signal through the signal receiving circuit 522 of another signal transmitter, thereby completing signal transmission and reception.

The signal receiving circuit 522 includes a current-voltage conversion module, which includes a positive receiving end dp and a negative receiving end dn, where the positive receiving end dp and the negative receiving end dn are also a positive output end dp and a negative output end dn of the signal transmitting circuit 521.

The positive receiving end dp and the negative receiving end dn are respectively connected to two ends of the secondary coil 532 of the magnetic coupler 530, and the current-voltage conversion module is configured to receive a current signal generated by the secondary coil 532 under the induction of the primary coil 531 of the magnetic coupler 530, and convert the current signal into a voltage signal to be output. In this specific embodiment, the current-voltage conversion module includes a common-mode terminal Vcm, a resistor R3 connecting the common-mode terminal Vcm with a positive receiving terminal dp, and a resistor R4 connecting the common-mode terminal Vcm with a negative receiving terminal dn, where a connection end of the resistor R3 and the positive receiving terminal dp serves as a first output terminal for outputting a first voltage signal; and the connection end of the resistor R4 and the negative receiving end dn is used as a second output end and is used for outputting a second voltage signal. In the embodiment of the present invention, the resistors R3 and R4 may be adjustable resistors, and the impedance matching between the signal receiving unit 522 and the magnetic coupler 530 can be realized by adjusting the resistors R3 and R4, so as to improve the receiving efficiency.

In this specific embodiment, the current-voltage conversion module further includes a filtering unit, where the filtering unit includes a resistor R1 and a fifth switch K5, the resistor R1 is connected to the positive input end dp and the resistor R3, and the current-voltage conversion module further includes a resistor R2 and a sixth switch K6, the resistor R2 is connected to the negative input end dn and the resistor R4; a capacitor C1 connected to the first output terminal and the second output terminal is also included. The resistor R1, the resistor R2 and the capacitor C1 play a role of filtering and stabilizing voltage, specifically, filtering a current signal and stabilizing output voltage, and a capacitance value of the capacitor C1 is 10pF to 30pF, preferably, in a specific embodiment of the present invention, a capacitance value of the capacitor C1 is 20pF. The on and off states of the fifth switch K5 and the sixth switch K6 are controlled by an enable signal, and both the fifth switch K5 and the sixth switch K6 are turned on when the signal receiving circuit 522 operates; when the signal receiving circuit 522 is not operating, the fifth switch K5 and the sixth switch K6 are turned off, and the signal receiving circuit 512 and the signal transmitting circuit 521 are turned off. When the current of the secondary coil 532 changes suddenly, a flyback voltage is generated on the resistor R3 and the resistor R4, and the resistors R1 and R2 are also used for isolating the influence of the flyback voltage on the signal transmitting circuit 521, and simultaneously realizing impedance matching between the primary coil 531 and the secondary coil 532 of the magnetic coupler 530. In an embodiment of the present invention, the resistors R3 and R4 may be variable resistors having resistance values ranging from 4 ohms to 1000 ohms, and the resistors R1 and R2 have the same resistance value of 200 ohms.

The digital processing module comprises a comparator 5221, a first output terminal of the current-voltage conversion module is connected to the positive input terminal of the comparator 5221, and a second output terminal of the current-voltage conversion module is connected to the negative input terminal of the comparator 5221. When the current signal received by the signal receiving circuit flows to dp-R1-R3-R4-R2-dn, a voltage V _ R3 is generated on the resistor R3, a voltage V _ R4 and a common mode terminal voltage Vcm are generated on the resistor R4, at this time, the positive input terminal voltage of the comparator 5221 is Vcm + V _ R3, the negative input terminal voltage is Vcm-V _ R3, and the comparator 5221 outputs a high level; on the contrary, when the current direction is dn-R2-R4-R3-R1-dp, the positive input end voltage of the comparator 5221 is Vcm-V _ R3, the negative input end voltage of the comparator 5221 is Vcm + V _ R4, and the comparator 5221 outputs a low level. Without the common mode voltage Vcm, one of the terminals of the comparator 5221 will have a negative voltage, and the lowest voltage at which the chip operates is usually ground. Therefore, the common mode terminal Vcm provides a common mode voltage for the comparator 5221 to avoid a negative voltage across the comparator.

Therefore, the signal receiving circuit 522 converts the received current signal to output a digital signal corresponding to the input signal din, and the digital signal output by the signal receiving circuit can be matched with the input signal din through the signal conversion, transmission, reception and re-conversion processes of the signal transmitting circuit 511 and the signal receiving circuit 522.

In this embodiment, the signal receiving circuit 522 further includes a signal filtering module 5222, and the signal filtering module 5222 is used to remove the error signal output by the digital processing module.

Fig. 8 is a schematic structural diagram of a signal transmitter according to another embodiment of the present invention.

In this specific embodiment, the signal transmitter includes a signal transmitting circuit 811, the signal transmitting circuit includes a digital control module 8111 and a current output module, and the current output module includes: a seventh switch K7 and an eighth switch K8; one end of the seventh switch K7 is connected to the current source, and the other end is connected to the negative end VSS of the power source; one end of the eighth switch K8 is connected to the current source, and the other end of the eighth switch K8 is connected to the forward output end dp; the negative output terminal dn is connected to the negative power terminal VSS.

Specifically, the power source terminal VDD is connected to the seventh switch K7 and the eighth switch K8 through a current mirror circuit, and serves as a constant current source Ib of the current output module, where the Ib may range from 100 μ a to 400 μ a, and the power consumption is low. A resistor R9 and a resistor R10 are sequentially connected between the seventh switch K7 and the negative power terminal VSS, a resistor R11 is connected between the eighth switch K8 and the positive output terminal dp, and a resistor R12 is connected between the negative output terminal dn and the negative power terminal VSS. The resistors R9, R10, R11, and R12 can prevent the flyback voltage generated when the current on the primary coil 531 of the magnetic combiner 530 changes abruptly from affecting the seventh switch K7 and the eighth switch K8. The resistors R9, R10, R11, and R12 may be variable resistors, and the impedance matching between the primary coil 531 and the secondary coil 532 of the magnetic coupler 530 may be achieved by adjusting the magnitudes of the resistors R9 to R12. In this embodiment, the resistances of the resistors R9, R10, R11, and R12 are equal.

In this specific embodiment, the seventh switch K7 and the eighth switch K8 are switches of the same type, the digital control module 8111 outputs control signals phi3 and phi3b, which are two control signals with opposite phases, according to a signal din to be transmitted, to control the seventh switch K7 and the eighth switch K8, respectively, when the seventh switch K7 is turned on, the eighth switch K8 is turned off, at this time, the current output module forms a current flowing from the seventh switch K7 to the negative terminal VSS of the power supply, no current signal is output between the positive output terminal dp and the negative output terminal dn, and the output current signal is 0; when the seventh switch K7 is turned off and the eighth switch K8 is turned on, an output current flowing from the positive output terminal dp to the negative output terminal dn through the primary coil 531 is formed.

Corresponds to a high level of a signal to be transmitted when a current signal is output, and corresponds to a low level of the signal to be transmitted when no current signal is output; or a low level corresponding to a signal to be transmitted when a current signal is output and a high level corresponding to a signal to be transmitted when no current signal is output.

The seventh switch K7 and the eighth switch K8 may include a plurality of switch elements therein, and the phi3b respectively include a plurality of sub-signals for respectively controlling the plurality of switch elements in the seventh switch K7 and the eighth switch K8 to be sequentially turned on or off, so as to prevent the current in the primary coil 531 from suddenly changing.

The current change on the primary coil 531 is sent to a signal receiving end through the secondary coil 532, and a signal corresponding to a signal din to be sent is output after processing, so that the signal din is sent and received.

Fig. 9 is a schematic structural diagram of a signal transmitter according to another embodiment of the present invention.

In this specific embodiment, the signal transmitter includes a signal sending circuit 911, the signal sending circuit includes a digital control module 9111 and a current output module, and the current output module includes: a ninth switch K9 and a tenth switch K10; one end of the ninth switch K9 is connected to the positive power supply terminal VDD, and the other end is connected to the negative power supply terminal VSS; one end of the tenth switch K10 is connected to the negative output end dn, and the other end is connected to the negative power supply end VSS; the forward output dp is connected to the positive supply terminal VDD.

Specifically, the ninth switch K9 and the tenth switch K10 are connected to the power supply negative terminal VSS through a current mirror circuit, so that the current Ib is outputted from the current output module to the power supply negative terminal VSS. The resistance R14 and the resistance R13 are sequentially connected between the ninth switch K9 and a positive power supply end VDD, the resistance R15 is further connected between a positive input end dp and the power supply VDD, the resistance R16 is further connected between a negative input end dn and the tenth switch K10, and the resistances R13, R14, R15 and R16 are used for avoiding the influence of generated flyback voltage on the ninth switch K9 and the tenth switch K10 when current on the primary coil 531 of the magnetic coupler 530 changes suddenly. The resistors R13, R14, R15, and R16 may be variable resistors, and by adjusting the size of the resistor R11, impedance matching between the primary coil 531 and the secondary coil 532 of the magnetic coupler 530 may be achieved. In this embodiment, the resistances of the resistors R13, R14, R15, and R16 are equal.

In this specific embodiment, the seventh switch K7 and the eighth switch K8 are switches of the same type, the digital control module 9111 is configured to output control signals phi4 and phi4b according to a signal din to be sent, and the digital control module 9111 is configured to output two control signals in opposite phases and is configured to control the ninth switch K9 and the tenth switch K10. In a specific real-time mode of the present invention, when the signal din is not input, the tenth switch K10 is turned on by the control signal phi4b output by the digital control module by default, the ninth switch K9 is turned off by phi4, the current output module generates a current signal from the positive output terminal dp to the negative output terminal dn through the primary coil 531, and at this time, the signal receiving circuit 522 outputs dout as a high level signal by default; when a signal din is input, the tenth switch K10 is turned off by the control signal phi4b, the ninth switch K9 is turned on by the phi4, current flows from the ninth switch K9 to the negative terminal VSS of the power supply, no current flows through the primary coil 531, and the signal dout output by the signal receiving circuit 522 is a low level signal.

The ninth switch K9 and the tenth switch K10 may include a plurality of switch elements, and the control signals phi4 and phi4b include a plurality of sub signals for respectively controlling the plurality of switch elements in the ninth switch K9 and the tenth switch K10 to be sequentially turned on or off, so as to avoid sudden change of current in the primary coil 531.

Correspondingly, when the current change of the primary coil 531 is transmitted to the signal receiving end through the secondary coil 532, a signal corresponding to the signal din to be transmitted is output after processing, so that the signal din is transmitted and received.

The signal transmitter comprises a signal sending circuit, and is used for converting a signal to be sent into a current signal to be sent, and the current signal is used as a carrier of the signal to be sent. The signal transmitter also comprises a signal receiving circuit which is used for receiving the current signal and converting the current signal into a digital signal to be output, so that the current signal is decoded. The current required by the signal transmitting and receiving process is far smaller than that required by photoelectric conversion, so that the power consumption can be reduced, and the cost can be reduced.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, many modifications and adaptations can be made without departing from the principle of the present invention, and such modifications and adaptations should also be considered as the scope of the present invention.

Claims

1. A signal transmitter, comprising a signal transmission circuit, the signal transmission circuit comprising: the digital control module is used for performing digital logic processing on the signal to be transmitted and outputting a digital control signal; the digital control module includes: a first terminal for outputting a first signal; a second terminal for outputting a second signal; a first inverting terminal for outputting a first inverted signal; a second inverting terminal for outputting a second inverted signal; the first signal and the second signal are two-phase non-overlapping signals, and the edges are not overlapped; the first reverse signal and the second reverse signal are also two-phase non-overlapping signals, and the edges are not overlapped; and the current output module is connected with the digital control module and used for outputting a current signal matched with the characteristics of the signal to be transmitted under the control of the digital control signal output by the digital control module, and comprises a positive output end and a negative output end which are respectively connected to two ends of the primary coil of the magnetic coupler.

2. The signal transmitter of claim 1, wherein the signal to be transmitted is a digital signal, and the digital control signal is configured to control a flowing direction of the current signal output by the current output module such that the current signal flowing in a forward direction corresponds to a high level of the signal to be transmitted and the current signal flowing in a reverse direction corresponds to a low level of the signal to be transmitted.

3. The signal transmitter of claim 1, wherein the digital control module has a digital control signal output; the current output module comprises a first switch, a second switch, a third switch and a fourth switch which are connected in sequence, a current source is connected between the first switch and the second switch, a positive output end is located between the first switch and the fourth switch, a negative output end is located between the second switch and the third switch, and the first switch, the second switch, the third switch and the fourth switch are respectively connected to a digital control signal output end of the digital control module.

4. The signal transmitter of claim 3, wherein the first terminal is connected to a third switch; the second end is connected to the fourth switch; the first reverse end is connected to the first switch; the second reverse end is connected to the second switch; the first signal and the first reverse signal are reverse signals to each other, and the second signal and the second reverse signal are reverse signals to each other.

5. The signal transmitter of claim 3, wherein the first switch, the second switch, the third switch and the fourth switch respectively have a plurality of switching elements, and the digital control signal is configured to sequentially turn on or off the plurality of switching elements in the first switch, the second switch, the third switch and the fourth switch.

6. The signal transmitter of claim 1, wherein the current output module comprises a seventh switch and an eighth switch; one end of the seventh switch is connected to the current source, and the other end of the seventh switch is connected to the negative end of the power supply; one end of the eighth switch is connected to the current source, and the other end of the eighth switch is connected to the positive output end; the negative output end is connected to the negative end of the power supply.

7. The signal transmitter of claim 1, wherein the current output module comprises a ninth switch and a tenth switch; one end of the ninth switch is connected to the positive end of the power supply, and the other end of the ninth switch is connected to the negative end of the power supply; one end of the tenth switch is connected to the negative output end, and the other end of the tenth switch is connected to the negative end of the power supply; the positive output end is connected to the positive power supply end.

8. The signal transmitter of claim 7, wherein the signal to be transmitted is a digital signal, and the digital control signal is used to control the current signal output by the current output module, and corresponds to a high level of the signal to be transmitted when the current signal is output and corresponds to a low level of the signal to be transmitted when no current signal is output; or a low level of a signal to be transmitted when there is a current signal output, and a high level of a signal to be transmitted when there is no current signal output.

9. The signal transmitter of any one of claims 1 to 8, further comprising a signal receiving circuit, the signal receiving circuit comprising: the current-voltage conversion module comprises a positive receiving end and a negative receiving end, the positive receiving end and the negative receiving end are respectively connected to two ends of a secondary coil of the magnetic coupler, and the current-voltage conversion module is used for receiving a current signal generated by the secondary coil under the induction of a primary coil of the magnetic coupler and converting the current signal into a voltage signal; and the digital processing module is connected with the current-voltage conversion module and used for processing the voltage signal output by the current-voltage conversion module and outputting a digital signal.

10. The signal transmitter of claim 9, wherein the current-to-voltage conversion module comprises a common mode terminal, a first resistor connecting the common mode terminal with a positive receiving terminal, and a second resistor connecting the common mode terminal with a negative receiving terminal, wherein a connection end of the first resistor with the positive receiving terminal serves as a first output terminal, and a connection end of the second resistor with the negative receiving terminal serves as a second output terminal.

11. The signal transmitter of claim 10, wherein the digital processing module comprises a comparator, and wherein the first output terminal is connected to a positive input terminal of the comparator, and the second output terminal is connected to a negative input terminal of the comparator.

12. The signal transmitter of claim 9, wherein the signal receiving circuit further comprises a signal filtering module connected to the digital processing module for removing an error signal output by the digital processing module.

13. A signal transmitter, comprising a signal receiving circuit, the signal receiving circuit comprising: the current-voltage conversion module comprises a positive receiving end and a negative receiving end, the positive receiving end and the negative receiving end are respectively connected to two ends of a secondary coil of the magnetic coupler, and the current-voltage conversion module is used for receiving a current signal generated by the secondary coil under the induction of a primary coil of the magnetic coupler and converting the current signal into a voltage signal; the current-voltage conversion module comprises a common-mode end, a first resistor and a second resistor, wherein the first resistor is connected with the common-mode end and a positive receiving end, the second resistor is connected with the common-mode end and a negative receiving end, the connecting end of the first resistor and the positive receiving end is used as a first output end, and the connecting end of the second resistor and the negative receiving end is used as a second output end; the digital processing module is connected with the current-voltage conversion module and used for processing the voltage signal output by the current-voltage conversion module and outputting a digital signal; the digital processing module comprises a comparator, wherein the first output end is connected to the positive input end of the comparator, and the second output end is connected to the negative input end of the comparator.

14. The signal transmitter of claim 13, wherein the signal receiving circuit further comprises a signal filtering module connected to the digital processing module for removing an error signal outputted from the digital processing module.