Multi-wiring compatible and quick-response analog quantity signal isolator

Abstract

The utility model discloses a multi-wiring compatible and quick-response analog quantity signal isolator, which aims to solve the problems of poor input mode compatibility, slow response and high cost of the conventional analog quantity signal isolator. The device is composed of an upper housing, a lower housing, a circuit board, an indicating lamp and an indicating window cover. A DC input voltage stabilization module, an operational amplification control module, an oscillation driving module and an isolation transformation output module are integrated on the circuit board. The thickness of the isolator is only 6.2 mm, the isolator is light, thin and portable, and the installation space is saved; two-wire system input, three-wire system input and four-wire system input are supported, and compatibility is high; by adopting a pure hardware scheme, the response speed is high and the cost is low. The internal circuit design is reasonable, power supply is stable, analog quantity signals can be effectively modulated and transmitted, input and output power supplies are respectively provided with a rectification filter circuit, power supply is stable, and accurate input and output of the analog quantity signals are guaranteed.

Description

TECHNICAL FIELD

[0001] The utility model relates to electronic circuit technical field, concretely relates to a kind of analog signal isolator of multi-wiring compatible and fast response. BACKGROUND

[0002] In the field of industrial automation, instrument measurement and power system monitoring, analog signal isolator is crucial, which guarantees signal stable transmission and system reliable operation. However, the products on the current market have significant defects. In terms of physical size, most isolators are 12.5-22.5mm thick, which occupies too much space in compact industrial control cabinet and other scenarios, limiting the number of equipment installations and system expandability. In terms of compatibility, most only support current source input, which cannot be compatible with widely used two-wire and three-wire transmitters, increasing the use cost and system complexity. In terms of technical solutions, digital solutions relying on MCU require programming, which not only increases the difficulty of production and maintenance, but also leads to slow response and high hardware cost, affecting the competitiveness of products in cost-sensitive markets. SUMMARY

[0003] The utility model solves the technical problems of an analog signal isolator with large thickness, poor input mode compatibility, slow response and high cost.

[0004] To achieve the above purpose, the utility model designs a kind of analog signal isolator of multi-wiring compatible and fast response, the analog signal isolator of multi-wiring compatible and fast response includes circuit board, the first terminal, second terminal, third terminal and fourth terminal are fixed on one side of the circuit board, the fifth terminal, sixth terminal, seventh terminal and eighth terminal are fixed on the other side;The first terminal, second terminal, third terminal and fourth terminal are input terminals of signal isolator, two-wire input signal is accessed to the first terminal and second terminal, three-wire input signal is accessed to the first terminal, second terminal and third terminal;The fifth terminal and sixth terminal are analog signal output terminals, and the seventh terminal and eighth terminal are power input terminals, which provide the required power for the isolator;

[0005] The circuit board is closely integrated with direct current input voltage stabilizing module, operational amplifier control module, oscillation driving module and isolation conversion output module;The thickness of the above-mentioned modules is less than or equal to 3.2mm;The direct current input voltage stabilizing module is connected with the seventh terminal and the eighth terminal;The output end of the isolation conversion output module is connected with the fifth terminal and the sixth terminal respectively, and the input end of the isolation conversion output module is connected to the first terminal, the second terminal, the third terminal and the fourth terminal respectively;

[0006] The operation amplifier control module adopts a high-speed processing circuit architecture composed of a differential amplification operation amplifier, a signal conditioning operation amplifier, and a DC / DC conversion circuit, thereby reducing signal processing levels and transmission delay; the DC / AC conversion circuit of the oscillation driving module takes a timer chip with high-speed trigger response and precise timing control capability as the core, is matched with an H-bridge circuit and a driving transformer, and realizes fast modulation and power amplification of signals; the signal input circuit, the current limiting circuit, the signal output modulation circuit, the AC / DC conversion circuit, the signal coupling adjustment circuit, and the signal output circuit of the isolation conversion output module are designed in coordination, high-speed response electronic components are adopted, the signal transmission path is optimized, and the loss and delay in the signal transmission process are reduced, so as to realize the fast response function of the analog signal isolator.

[0007] The multi-wiring compatible and fast response analog signal isolator comprises an upper shell, a lower shell, an indicator lamp, and an indicator window cover; the upper shell and the lower shell are fixedly connected to form a cavity, the circuit board is arranged in the internal cavity of the upper shell and the lower shell, and the top end of the circuit board is provided with the indicator lamp; the indicator window cover is fixedly connected to the top of the upper shell and the lower shell; the thicknesses of the upper shell, the lower shell, and the circuit board are less than or equal to 1.0 mm.

[0008] The upper shell is stably connected to the lower shell through buckling.

[0009] The indicator window cover is fixedly connected to the top of the upper shell and the lower shell through buckling, corresponds to the indicator lamp, and is made of transparent or translucent material, is used for displaying the state of the indicator lamp on the circuit board, and displays green when the indicator lamp is normally powered on.

[0010] The first terminal, the second terminal, the third terminal, the fourth terminal, the fifth terminal, the sixth terminal, the seventh terminal, and the eighth terminal are respectively fixedly connected to the circuit board through welding.

[0011] The indicator lamp is fixedly connected to the circuit board through welding.

[0012] The DC input voltage stabilizing module on the circuit board comprises an input protection circuit, an input filter circuit, a voltage stabilizing chip, and an output filter circuit; the DC input voltage stabilizing module is provided with at least two input ports, a DC power output end is connected to the voltage stabilizing chip through an input protection circuit and an input filter circuit composed of an inductor, a diode, a transient voltage suppressor, and multiple capacitors, and the voltage stabilizing chip is further connected to an output filter circuit composed of an inductor, a resistor, a diode, and multiple capacitors.

[0013] The DC input voltage stabilizing module on the circuit board is used for reducing the input power supply and stabilizing the input power supply into the voltage required by the ultra-thin signal isolator.

[0014] The input protection circuit includes an inductor for suppressing common mode interference, a voltage-dependent resistor and a transient voltage suppressor diode for overvoltage protection, a diode for preventing reverse connection of the power supply, and a fuse for overcurrent protection; the input filter circuit is composed of multiple capacitors for filtering out high-frequency noise and ripple in the input power supply; the voltage regulator chip pin IN is connected to the input voltage, the pin EN is used for enable control, and the pin FB is used for voltage feedback to adjust the output voltage; the output filter circuit includes an inductor and multiple capacitors for further smoothing the output voltage, and a diode provides a loop for inductor freewheeling.

[0015] The input signal of the operational amplifier control module on the circuit board is connected to the non-inverting input terminal and the inverting input terminal of the differential amplifier operational amplifier through resistors, respectively, and the output terminal of the differential amplifier operational amplifier is connected to the non-inverting input terminal of the signal conditioning operational amplifier through a capacitor; the output terminal of the signal conditioning operational amplifier is connected to the DC / DC conversion circuit through a diode; an NPN transistor in the DC / DC conversion circuit is connected in parallel with a resistor; the output voltage is also connected to the NPN transistor through a resistor, and is further connected to a filter circuit composed of a capacitor and an inductor before being connected to the power supply chip; the power supply output pin of the power supply chip is connected to the load after being grounded through a resistor and a capacitor.

[0016] The differential amplifier operational amplifier receives differential input signals, and after amplification, operation, rectification and other processes, outputs precise analog signals to meet specific signal output requirements; the amplified signal output by the differential amplifier operational amplifier is further processed by the signal conditioning operational amplifier to meet the requirements of the subsequent DC / DC conversion circuit, the output terminal of the differential amplifier operational amplifier is connected to the DC / DC conversion circuit through a diode, and the diode functions as a unidirectional conductor to prevent the signal of the DC / DC conversion circuit from flowing back to the differential amplifier operational amplifier; the DC / DC conversion circuit converts the input DC voltage into a DC power supply of different voltage levels to provide a suitable power supply for the subsequent circuit; the circuit composed of resistors and capacitors stabilizes the output voltage and filters out high-frequency interference to provide a stable working voltage and suitable signals for the load.

[0017] The oscillation drive module on the circuit board is mainly composed of a DC / AC conversion circuit, which is connected to a voltage source through a filter circuit; the DC / AC conversion circuit takes a timer chip as the core and is connected to a drive transformer on one side of an H-bridge circuit through resistors and capacitors.

[0018] The trigger pin in the timer chip is used to accept external trigger signals to start or adjust the DC / AC conversion process according to the signals; at the same time, the input signals are processed by the internal logic circuit to output complementary control signals to accurately control the on and off timing of the field effect transistor in the H-bridge circuit, realizing the conversion from DC to AC; the oscillator pin in the timer chip is externally connected with a high-precision, low-temperature-drift capacitor and resistor to form an oscillator circuit, and the internal circuit of the timer chip cooperates with the external elements to determine the oscillation frequency of the entire DC / AC conversion, ensuring the frequency stability of the output AC signal to meet the working requirements of the subsequent circuit and improve the stability and reliability of the entire circuit system.

[0019] The alternating current output by the H-bridge circuit passes through the primary winding of the transformer, and the electromagnetic induction principle is used to induce the corresponding AC voltage on the secondary winding of the transformer, thereby transmitting energy to the subsequent circuit to provide the required AC power or signal for other functional modules. The resistance in the circuit is used for current limiting and filtering to prevent excessive driving current from damaging the timer chip or the field effect transistor, and the capacitor has the functions of signal coupling, filtering and voltage stabilization.

[0020] The oscillation driving module can modulate and power amplify the signal, realize electrical isolation of the signal by means of the transformer, enhance the anti-interference ability of the signal, and realize efficient transmission of the signal.

[0021] The isolation conversion output module on the circuit board comprises a signal input circuit, a current limiting circuit, a signal output modulation circuit, a first AC / DC conversion circuit, a second AC / DC conversion circuit, a signal coupling adjustment circuit and a signal output circuit; the input end of the signal input circuit is electrically connected with an external input signal source, and the output end of the signal input circuit is connected with the current limiting circuit. The output end of the current limiting circuit is further connected to the input end of the second AC / DC conversion circuit; the power input end of the signal output modulation circuit is connected with the output end of the second AC / DC conversion circuit to obtain a stable power supply; the other port of the signal output modulation circuit is connected with the input end of the signal coupling adjustment circuit through a transformer to realize signal modulation and transmission; the first AC / DC conversion circuit and the signal coupling adjustment circuit are connected with each other to provide necessary power support for the signal coupling adjustment circuit; the output end of the signal coupling adjustment circuit is connected with the input end of the signal output circuit to finally output the processed and adjusted signal; at the same time, the first AC / DC conversion circuit and the second AC / DC conversion circuit are connected through a transformer.

[0022] The signal input circuit is composed of a plurality of transient diodes, a plurality of inductors and a plurality of voltage stabilizing tubes for signal transmission, filtering and protection; the diode D14 constitutes an anti-reverse circuit to prevent reverse connection of the signal input.

[0023] The current limiting circuit is composed of a fuse, a plurality of current limiting resistors, a triode and a MOS tube, and current limiting protection is performed when an overcurrent is input to prevent a safety risk caused by excessive energy;

[0024] The signal output modulation circuit is composed of a field effect tube, a capacitor and a resistor; the signal output modulation circuit performs modulation processing on an input signal, changes the frequency, amplitude or phase characteristics of the signal through the switching action of the field effect tube in combination with the adjustment of the signal parameters of the capacitor and the resistor, makes the signal meet the transmission and processing requirements of subsequent circuits, so that effective transmission of the signal and implementation of specific functions are realized;

[0025] The first AC / DC conversion circuit is composed of a diode and a capacitor, and is used for converting an alternating current signal into a direct current signal to provide a stable direct current power supply for other circuit modules; the first AC / DC conversion circuit transmits a signal to a second AC / DC conversion circuit through a transformer, and the second AC / DC conversion circuit further provides a suitable direct current working power supply for the signal output modulation circuit and other modules to ensure normal operation of these circuits;

[0026] The signal coupling and adjusting circuit is composed of a field effect tube, a capacitor and a resistor, and is used for realizing coupling and adjusting of the signal, making the signal meet the output requirements, and effectively interacting the signal between circuits to ensure that the signal can be accurately transmitted to subsequent circuits;

[0027] The signal output circuit is composed of an operational amplifier, a MOS tube, a plurality of resistors and a potentiometer, and is used for receiving a signal transmitted from a previous stage circuit, processing and adjusting the signal transmitted from the previous stage circuit, and finally outputting a signal meeting the requirements for use by a subsequent stage circuit or a load.

[0028] The utility model has the advantages and beneficial effects that:

[0029] 1. Strong compatibility and wide application range. The utility model supports two-wire system, three-wire system and four-wire system (current source) input, and can flexibly select a suitable wiring mode according to a previous stage device. Whether it is a transmitter or a current source device, it can be adapted to it, has strong inclusiveness, expands the application scenarios of the product, and meets the diversified needs of different users.

[0030] 2. Fast response speed and low cost. The utility model adopts a pure hardware scheme and does not need to process data and burn programs by using an MCU. This not only avoids the response delay problem caused by program processing in a digital scheme, greatly improves the response speed, but also reduces the development cost of the MCU and related programs, reduces the overall production cost, improves the performance of the product, and enhances the market competitiveness.

[0031] 3. The circuit design is reasonable, and the power supply is stable. The internal circuit design is scientific, the transformer can realize two-way power supply output, the input and output power supply are respectively provided with rectifier filter circuit, the stable isolation conversion output module can ensure that the signal is effectively modulated and transmitted, and the accurate input and output of the analog signal are ensured.

[0032] 4. Light and thin, portable, saves installation space. The overall thickness is only 6.2 mm, compared with the traditional isolators with a thickness of 12.5 mm and 22.5 mm, the volume is significantly reduced. This feature makes it obvious in the installation of limited space, can adapt to the installation demand of compact space, and is beneficial to the dense installation of multiple devices, improves the space utilization. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is a product structure schematic view of the utility model;

[0034] Figure 2 is a scheme block diagram of the ultrathin signal isolator;

[0035] Figure 3 is a DC input voltage stabilizing module;

[0036] Figure 4 is an operational amplifier control module;

[0037] Figure 5 is an oscillation driving module;

[0038] Figure 6 is an isolation conversion output module. DETAILED DESCRIPTION

[0039] The specific embodiments of the utility model are further described below in combination with the drawings and examples. The following examples are only used to more clearly illustrate the technical scheme of the utility model, and cannot limit the protection scope of the utility model.

[0040] Example 1:

[0041] A kind of analog signal isolator of multi-wiring compatible and fast response, as shown in Figure 1 、 Figure 2 It includes circuit board 12, first terminal 4, second terminal 5, third terminal 6 and fourth terminal 7 are fixed on one side of circuit board 12, fifth terminal 8, sixth terminal 9, seventh terminal 10 and eighth terminal 11 are fixed on the other side;First terminal 4, second terminal 5, third terminal 6 and fourth terminal 7 are input terminals of signal isolator, two-wire input signal is connected to first terminal 4 and second terminal 5, three-wire input signal is connected to first terminal 4, second terminal 5 and third terminal 6;Fifth terminal 8 and sixth terminal 9 are analog signal output terminals, seventh terminal 10 and eighth terminal 11 are power input terminals to provide power for isolator.

[0042] The circuit board 12 is closely integrated with a direct current input voltage stabilizing module, an operational amplifier control module, an oscillation driving module and an isolation conversion output module; the thicknesses of the above modules are less than or equal to 3.2 mm; the direct current input voltage stabilizing module is connected with the seventh terminal 10 and the eighth terminal 11; the output ends of the isolation conversion output module are connected with the fifth terminal 8 and the sixth terminal 9 respectively, and the input ends of the isolation conversion output module are connected to the first terminal 4, the second terminal 5, the third terminal 6 and the fourth terminal 7 respectively.

[0043] A multi-wiring compatible and fast response analog signal isolator comprises an upper shell 1, a lower shell 13, an indicator lamp 3 and an indicator window cover 2; the upper shell 1 is fixedly connected with the lower shell 13 to form a cavity, a circuit board 12 is arranged in the internal cavity of the lower shell 13 and the upper shell 1, and the indicator lamp 3 is arranged at the top end of the circuit board 12; the indicator window cover 2 is fixedly connected at the top of the upper shell 1 and the lower shell 13; the thicknesses of the upper shell, the lower shell and the circuit board are less than or equal to 1.0 mm.

[0044] The upper shell 1 is stably connected with the lower shell 13 through buckling.

[0045] The first terminal 4, the second terminal 5, the third terminal 6, the fourth terminal 7, the fifth terminal 8, the sixth terminal 9, the seventh terminal 10 and the eighth terminal 11 are fixedly connected with the circuit board 12 through welding respectively.

[0046] The indicator lamp 3 is fixedly connected at the top end of the circuit board 12 through welding.

[0047] Embodiment 2:

[0048] The direct current input voltage stabilizing module comprises an input protection circuit, an input filter circuit, a voltage stabilizing chip and an output filter circuit; the direct current input voltage stabilizing module is provided with at least two input ports, a direct current power supply output end is connected to the voltage stabilizing chip IC2, an inductor L3, resistors R2 and R3, a diode D2 and an output filter circuit composed of multiple capacitors C5, C24, C15, C16, C17, C21 and C23 through an input protection circuit and an input filter circuit composed of inductors L1 and L2, a diode D1, a transient voltage suppression diode TVS1 and multiple capacitors C19, C33 and C20 and a capacitor C2;

[0049] The direct current input voltage stabilizing module is used for reducing the input power supply and stabilizing the input power supply into a voltage required by the ultra-thin signal isolator.

[0050] The input protection circuit includes inductors L1 and L2 for suppressing common mode interference, a voltage-sensitive resistor RV1 and a transient voltage suppression diode TVS1 for overvoltage protection, a diode D1 for preventing reverse connection of the power supply, and a fuse F1 for overcurrent protection; the input filter circuit is composed of multiple capacitors C19, C33, C20 and C2 for filtering high-frequency noise and ripple in the input power supply; the voltage regulator chip IC1 has a pin IN connected to the input voltage, a pin EN for enabling control, and a pin FB for voltage feedback to regulate the output voltage; the output filter circuit includes an inductor L3 and multiple capacitors C5, C24, C15, C16, C17, C21 and C23 for further smoothing the output voltage, and a diode for providing a circuit for inductive freewheeling.

[0051] Example 3

[0052] The input signal of the operational amplifier control module is connected to the non-inverting input terminal (pin 3) and the inverting input terminal (pin 2) of the differential amplification operational amplifier U1 through resistors R20 and R21, respectively, and the output terminal (pin 6) of the differential amplification operational amplifier U1 is connected to the non-inverting input terminal of the signal conditioning operational amplifier U3B through a capacitor C27. The output terminal of the signal conditioning operational amplifier U3B is connected to the DC / DC conversion circuit through a diode D7; the NPN transistor in the DC / DC conversion circuit is connected in parallel with resistors R16, R17, R24 and R25; the output voltage is also connected to the NPN transistor through resistors R16 and R17, and is further connected to the power supply chip IC1 after passing through a filter circuit composed of capacitors C14 and C6 and an inductor L6; the power supply output pin (pin 5) of the power supply chip IC1 is connected to the load after being connected to the ground through a resistor R18 and a capacitor C.

[0053] The differential amplification operational amplifier U1 receives differential input signals, amplifies, operates and rectifies them, and outputs precise analog signals to meet specific signal output requirements; the amplified signals of the differential amplification operational amplifier U1 are further processed by the signal conditioning operational amplifier U3B to meet the requirements of the subsequent DC / DC conversion circuit; the output terminal of the differential amplification operational amplifier U1 is connected to the DC / DC conversion circuit through a diode D7, which functions as a one-way conductor to prevent the signals of the DC / DC conversion circuit from flowing back to the differential amplification operational amplifier U1; the DC / DC conversion circuit converts the input DC voltage into DC power of different voltage levels to provide appropriate power supply for the subsequent circuit; the filtered signals are further processed; the circuit composed of the resistor R18 and the capacitor C stabilizes the output voltage and filters high-frequency interference to provide a stable working voltage and appropriate signals for the load.

[0054] Example 4

[0055] The oscillation driving module mainly consists of a DC / AC conversion circuit. The DC / AC conversion circuit is connected with a voltage source VCC1 through a filter circuit composed of a capacitor C4. The DC / AC conversion circuit takes a timer chip U2 as a core, and is connected with a drive transformer T1A on one side of an H-bridge circuit (composed of field effect tubes Q1, Q2, Q3 and Q4) through resistors R6, R7, R8, R9, R10 and R11, and capacitors C8, C9, C10, C11 and C50.

[0056] The trigger pins (-TRG pin 6 and +TRG pin 8) in the timer chip U2 are used to accept external trigger signals to start or adjust the DC / AC conversion process according to the signals. At the same time, the input signals are processed by an internal logic circuit to output complementary control signals, so as to accurately control the on and off timing of the field effect tubes Q1, Q2, Q3 and Q4 in the H-bridge circuit, and realize the conversion from direct current to alternating current. The oscillator pin (OSC pin 13) in the timer chip U2 is externally connected with a high-precision, low-temperature-drift capacitor C8 and a resistor R6 to form an oscillator circuit. The internal circuit of the timer chip U2 cooperates with the external elements to determine the oscillation frequency of the entire DC / AC conversion, so as to ensure the frequency stability of the output alternating current signal, meet the working requirements of the subsequent circuit, and improve the stability and reliability of the entire circuit system.

[0057] The alternating current output by the H-bridge circuit passes through the primary winding of the transformer T1A, and a corresponding alternating voltage is induced on the secondary winding of the transformer T1A by using the principle of electromagnetic induction, so as to transmit energy to the subsequent circuit and provide the required alternating current power or signal for other functional modules. The resistors R6, R7, R8, R9, R10 and R11 in the circuit are used for current limiting and filtering to prevent excessive driving current from damaging the timer chip U2 or the field effect tubes Q1, Q2, Q3 and Q4. The capacitors C4, C8, C9, C10, C11 and C50 have the functions of signal coupling, filtering and voltage stabilization.

[0058] The oscillation driving module can modulate and power amplify signals, realize electrical isolation of signals by means of the transformer T1A, enhance the anti-interference ability of signals, and realize efficient transmission of signals.

[0059] Example 5:

[0060] The isolation conversion output module comprises a signal input circuit, a current limiting circuit, a signal output modulation circuit, a first AC / DC conversion circuit, a second AC / DC conversion circuit, a signal coupling adjustment circuit and a signal output circuit; the input end of the signal input circuit is electrically connected with an external input signal source, and the output end of the signal input circuit is connected with the current limiting circuit. The output end of the current limiting circuit is further connected with the input end of the second AC / DC conversion circuit; the power supply input end of the signal output modulation circuit is connected with the output end of the second AC / DC conversion circuit, so as to obtain a stable power supply; the other port of the signal output modulation circuit is connected with the input end of the signal coupling adjustment circuit through the transformer T1B, so as to realize the modulation and transmission of the signal; the first AC / DC conversion circuit and the signal coupling adjustment circuit are connected with each other, and provide necessary power supply support for the signal coupling adjustment circuit; the output end of the signal coupling adjustment circuit is connected with the input end of the signal output circuit, and finally outputs the signal processed and adjusted; meanwhile, the first AC / DC conversion circuit and the second AC / DC conversion circuit are connected through the transformer T1B.

[0061] The signal input circuit is composed of a plurality of transient diodes TVS2, TVS3, TVS4, a plurality of inductors L4, L8, L9, L10 and a plurality of voltage stabilizing tubes D10, D12, and is used for signal transmission, filtering and protection; the diode D14 constitutes an anti-reverse circuit to prevent signal input from being reversed.

[0062] The current limiting circuit is composed of a fuse F2, a plurality of current limiting resistors R22, R23, R26, R37, a triode Q5 and a MOS tube Q11, and performs current limiting protection when overcurrent is input to prevent safety risks caused by excessive energy.

[0063] The signal output modulation circuit is composed of field effect tubes Q6, Q7, Q8, Q9, capacitors C15, C43, C44, C45 and resistors R13, R14, R32, R33, R51; the signal output modulation circuit performs modulation processing on the input signal, changes the frequency, amplitude or phase characteristics of the signal through the switching action of the field effect tube, adjusts the signal parameters of the capacitor and the resistor, makes the signal meet the transmission and processing requirements of the subsequent circuit, so as to realize the effective transmission of the signal and the realization of specific functions.

[0064] The first AC / DC conversion circuit is composed of diodes D3, D4, D8, D9, capacitors C28, C29, C30, C31, C42, C44 and C45, and is used for converting alternating current signals into direct current signals to provide stable direct current power supply for other circuit modules. The first AC / DC conversion circuit transmits signals to the second AC / DC conversion circuit through the transformer T1B, and the second AC / DC conversion circuit further provides appropriate direct current working power supply for the signal output modulation circuit and other modules, so as to ensure the normal operation of these circuits.

[0065] The signal coupling and adjusting circuit is composed of field effect tubes Q10 and Q11, capacitors C12, C25, C35 and C48, and resistors R15, R24, R86 and R87, and is used for realizing signal coupling and adjusting, making the signal meet the output requirement, and effectively exchanging the signal between circuits to ensure that the signal can be accurately transmitted to the subsequent circuit.

[0066] The signal output circuit is composed of an operational amplifier U3A, a MOS tube Q5, a plurality of resistors R27, R28, R29 and R36, and a potentiometer A1, and is used for receiving the signal transmitted from the previous stage circuit, processing and adjusting the signal transmitted from the previous stage circuit, and finally outputting the signal meeting the requirement for the subsequent stage circuit or load.

[0067] In view of the above detailed description, these and other changes can be made to the embodiments, and the written description includes the best mode of the embodiments disclosed in the utility model. The patent scope obtained by the utility model is defined by the claims, and the claims are not limited by the disclosure, and the protection scope of the utility model is not limited to this. Any person skilled in the art in the range disclosed by the utility model, according to the technical scheme and the concept of the utility model, makes equivalent replacement or change, which is within the protection scope of the utility model.

Claims

1. A multi-wire compatible and fast-response analog signal isolator, characterized in that, The circuit board (12) has a first terminal (4), a second terminal (5), a third terminal (6) and a fourth terminal (7) fixed on one side, and a fifth terminal (8), a sixth terminal (9), a seventh terminal (10) and an eighth terminal (11) fixed on the other side. The first terminal (4), the second terminal (5), the third terminal (6) and the fourth terminal (7) are the input terminals of the signal isolator. Two-wire input signals are connected to the first terminal (4) and the second terminal (5), and three-wire input signals are connected to the first terminal (4), the second terminal (5) and the third terminal (6). The fifth terminal (8) and the sixth terminal (9) are analog signal output terminals, and the seventh terminal (10) and the eighth terminal (11) are power input terminals. The circuit board (12) is tightly integrated with a DC input voltage regulator module, an operational amplifier control module, an oscillation drive module and an isolation converter output module; the thickness of the above modules is less than or equal to 3.2mm; the DC input voltage regulator module is connected to the seventh terminal (10) and the eighth terminal (11); the output terminal of the isolation converter output module is connected to the fifth terminal (8) and the sixth terminal (9) respectively, and the input terminal of the isolation converter output module is connected to the first terminal (4), the second terminal (5), the third terminal (6) and the fourth terminal (7) respectively.

2. The multi-wire compatible and fast-response analog signal isolator according to claim 1, characterized in that, It includes an upper housing (1), a lower housing (13), an indicator light (3), and an indicator window cover (2); the upper housing (1) and the lower housing (13) are fixedly connected to form a cavity, and the circuit board (12) is located in the internal cavity of the lower housing (13) and the upper housing (1), and the top of the circuit board (12) is provided with an indicator light (3); the indicator window cover (2) is fixedly connected to the top of the upper housing (1) and the lower housing (13); the thickness of the upper housing, the lower housing, and the circuit board is less than or equal to 1.0 mm.

3. The multi-wire compatible and fast-response analog signal isolator according to claim 2, characterized in that, The upper housing (1) is securely connected to the lower housing (13) by a snap fastener.

4. The multi-wire compatible and fast-response analog signal isolator according to claim 2, characterized in that, The indicator window cover (2) is fixed to the top of the upper housing (1) and the lower housing (13) by a snap fastener, corresponding to the indicator light (3).

5. The multi-wire compatible and fast-response analog signal isolator according to claim 2, characterized in that, The indicator light (3) is fixed to the top of the circuit board (12) by welding.

6. The multi-wire compatible and fast-response analog signal isolator according to claim 1, characterized in that, The first terminal (4), the second terminal (5), the third terminal (6), the fourth terminal (7), the fifth terminal (8), the sixth terminal (9), the seventh terminal (10) and the eighth terminal (11) are respectively fixed to the corresponding positions on the circuit board (12) by welding.

7. The multi-wire compatible and fast-response analog signal isolator according to claim 1, characterized in that, The DC input voltage regulator module on the circuit board (12) includes an input protection circuit, an input filter circuit, a voltage regulator chip, and an output filter circuit. The DC input voltage regulator module has at least two input ports. The DC power output terminal is connected to the voltage regulator chip through an input protection circuit and an input filter circuit composed of an inductor, a diode, a transient suppression diode, and multiple capacitors. The voltage regulator chip is further connected to the output filter circuit composed of an inductor, a resistor, a diode, and multiple capacitors.

8. The multi-wire compatible and fast-response analog signal isolator according to claim 1, characterized in that, The input signals of the operational amplifier control module on the circuit board (12) are connected to the non-inverting input and inverting input of the differential operational amplifier through resistors, respectively. The output of the differential operational amplifier is connected to the non-inverting input of the signal conditioning operational amplifier through a capacitor. The output of the signal conditioning operational amplifier is connected to the DC / DC conversion circuit through a diode. A resistor is connected to the side of the NPN transistor in the DC / DC conversion circuit. The output voltage is connected to the NPN transistor through a resistor and then connected to the power supply chip through a filter circuit. The power output pin of the power supply chip is grounded through a resistor and a capacitor and then connected to the load.

9. The multi-wire compatible and fast-response analog signal isolator according to claim 1, characterized in that, The oscillation drive module on the circuit board (12) is mainly composed of a DC / AC conversion circuit. The DC / AC conversion circuit is connected to the voltage source through a filter circuit. The DC / AC conversion circuit is based on a timer chip and is connected to the drive transformer on one side of the H-bridge circuit through resistors and capacitors.

10. The multi-wire compatible and fast-response analog signal isolator according to claim 1, characterized in that, The isolated conversion output module on the circuit board (12) includes a signal input circuit, a current limiting circuit, a signal output modulation circuit, a first AC / DC conversion circuit, a second AC / DC conversion circuit, a signal coupling adjustment circuit, and a signal output circuit. The input terminal of the signal input circuit is electrically connected to an external input signal source, and the output terminal of the signal input circuit is connected to the current limiting circuit. The output terminal of the current limiting circuit is then connected to the input terminal of the second AC / DC conversion circuit. The power input terminal of the signal output modulation circuit is connected to the output terminal of the second AC / DC conversion circuit. The other port of the signal output modulation circuit is connected to the input terminal of the signal coupling adjustment circuit through a transformer. The first AC / DC conversion circuit and the signal coupling adjustment circuit are interconnected. The output terminal of the signal coupling adjustment circuit is connected to the input terminal of the signal output circuit. At the same time, the first AC / DC conversion circuit and the second AC / DC conversion circuit are connected through a transformer.

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