Isolation voltage regulation reference circuit with failure protection

Abstract

The utility model provides an isolation voltage regulation reference circuit with failure protection, which comprises a signal isolation transmission module, a signal failure protection module and a signal-to-analog voltage module, the input end of the signal isolation transmission module is electrically connected with the PWM output end of a monitoring module, and the signal isolation transmission module is used for isolating and amplifying PWM signals; the input end of the signal failure protection module is electrically connected with the output end of the signal isolation transmission module, and the signal failure protection module is used for monitoring whether the PWM signal is normal or not; the input end of the signal-to-analog voltage module is electrically connected with the output end of the signal failure protection module, and the signal-to-analog voltage module is used for converting and filtering the PWM signal into direct-current reference voltage; through cooperative work of the signal isolation transmission module, the signal failure protection module and the signal-to-analog voltage module, the problems that PWM signal transmission in a communication base station is easily interfered and there is no backup scheme in case of a fault are effectively solved, it is ensured that the rectification module can provide a stable and reliable DC power supply under different working conditions, and the reliability of the system is improved. And the stability and the reliability of the communication network are enhanced.

Description

Technical Field

[0001] The utility model relates to the field of switching power supplies for communication base stations, and particularly relates to an isolated voltage regulating reference circuit with failure protection. Background Art

[0002] In the switching power supply system of a communication base station, the rectification module is responsible for rectifying alternating current into direct current and providing a stable direct current power supply for communication devices. The main functions of the rectification module include converting alternating current into direct current and outputting voltage and current according to the settings of the monitoring module. The rectification module occupies a very important position in the communication power supply system. It is one of the key infrastructures of the communication network and is responsible for providing a stable and reliable direct current power supply for communication devices. A power supply system consists of a monitoring unit and several rectification modules. The monitoring and rectification modules are usually connected by PWM signals or RS-485 communication methods. The monitoring unit is responsible for monitoring and coordinating the work of each rectification module, detecting various parameters of the system, processing alarm information, and providing a human-machine interface for users to operate, so as to control the operation of the entire power supply system. The monitoring module can adjust the voltage and current output of the rectification module according to the set parameters. This includes meeting the equalizing and floating charging requirements of the battery, voltage regulation requirements, etc.

[0003] The patent with publication number CN113625814B discloses a voltage regulating circuit for a switching power supply, which includes a voltage stabilizing control circuit, a reference voltage regulating circuit, and a PWM signal filtering and amplifying circuit; the PWM signal filtering and amplifying circuit is used to obtain a first voltage signal according to the externally applied PWM voltage regulating signal after low-pass filtering; the reference voltage regulating circuit regulates the reference voltage source inside the switching power supply according to the first voltage signal and outputs the regulated reference voltage source as a direct current voltage source; the voltage stabilizing control circuit is used to stabilize the direct current voltage source output by the reference voltage regulating circuit; since the externally applied PWM voltage regulating signal is converted into a first voltage signal and the switching power supply is regulated according to the first voltage signal, the adjustable switching power supply can not only receive the externally applied PWM voltage regulating signal to control the adjustable power supply output, but also default to output a direct current power supply with a preset voltage value when there is no externally applied PWM voltage regulating signal.

[0004] In the complex usage environment of the base station, the transmission of PWM signals is vulnerable to interference, and the transmission of PWM signals is prone to failure. In the unattended state of the base station, once the transmission of PWM signals fails, there is no backup solution, which further causes the communication network to be unable to operate normally, thereby reducing the stability and reliability of the communication network. Content of the Utility Model

[0005] In view of this, the present utility model proposes an isolated voltage regulating reference circuit with failure protection. Through the collaborative work of the signal isolation and transmission module, the signal failure protection module, and the signal-to-analog voltage module, it effectively solves the problems that the PWM signal transmission in communication base stations is vulnerable to interference and there is no backup solution in case of faults, ensuring that the rectifier module can provide a stable and reliable DC power supply under different working conditions and enhancing the stability and reliability of the communication network.

[0006] The technical solution of the present utility model is realized as follows: The present utility model provides an isolated voltage regulating reference circuit with failure protection, including: a signal isolation and transmission module, a signal failure protection module, and a signal-to-analog voltage module. Among them,

[0007] The input end of the signal isolation and transmission module is electrically connected to the output end of the PWM of the monitoring module, and is used for isolating and amplifying the PWM signal;

[0008] The input end of the signal failure protection module is electrically connected to the output end of the signal isolation and transmission module, and is used for monitoring whether the PWM signal is normal;

[0009] The input end of the signal-to-analog voltage module is electrically connected to the output end of the signal failure protection module, and is used for converting and filtering the PWM signal into a DC reference voltage.

[0010] Based on the above technical solution, preferably, the signal isolation and transmission module includes a filtering unit, an isolation unit, and an amplifying unit. Among them, the input end of the filtering unit is electrically connected to the output end of the PWM of the monitoring module, and is used for filtering the PWM input signal; the input end of the isolation unit is electrically connected to the output end of the filtering unit, and is used for isolating and transmitting the filtered PWM input signal; the input end of the amplifying unit is electrically connected to the output end of the isolation unit, and is used for amplifying the isolated PWM input signal.

[0011] Based on the above technical solution, preferably, the signal isolation and transmission module includes a resistor R1 and a capacitor C1. Among them, the output end of the PWM of the monitoring module is electrically connected to the resistor R1, the common end of the PWM of the monitoring module is electrically connected to the capacitor C1 and the negative electrode of the input end of the isolation unit respectively, and the other end of the capacitor C1 is electrically connected to the other end of the resistor R1 and the positive electrode of the input end of the isolation unit respectively.

[0012] Based on the above technical solution, preferably, the isolation unit includes an optocoupler U1, a resistor R3, and a resistor R4. Among them, pin 2 of the optocoupler U1 serves as the positive electrode of the input end of the isolation unit, pin 3 of the optocoupler U1 serves as the negative electrode of the input end of the isolation unit, pins 6 and 8 of the optocoupler U1 are commonly electrically connected to the resistor R4, pin 7 of the optocoupler U1 is electrically connected to the resistor R3, and the other end of the resistor R3 is electrically connected to pin 5 of the optocoupler U1.

[0013] Based on the above technical solutions, preferably, the amplification unit includes resistor R2, resistor R5, and triode Q1. Among them, the common connection of pin 6 and pin 8 of optocoupler U1 is also electrically connected to resistor R2. The other end of resistor R2 is electrically connected to the base of triode Q1. The emitter of triode Q1 is electrically connected to the common terminal of pin 5 of optocoupler U1 and resistor R3 and grounded. The collector of triode Q1 is respectively electrically connected to resistor R5 and the output terminal of signal isolation and transmission module 1. The other end of resistor R5 is respectively electrically connected to the other end of capacitor C2 and resistor R4, and is connected to an external power supply. The other end of capacitor C2 is grounded.

[0014] Based on the above technical solutions, preferably, the signal failure protection module includes resistors R6, R7, R8, capacitors C3, C4, diode D1, and NAND gates U2, U3, U4, U5. Among them, the output terminal of the signal isolation and transmission module is electrically connected to resistor R6, the second input terminal of NAND gate U5, and the first input terminal of NAND gate U4. The second input terminal of NAND gate U4 is respectively electrically connected to the output terminal of NAND gate U2 and resistor R7. The output terminal of NAND gate U4 is electrically connected to capacitor C3. The other end of capacitor C3 is respectively electrically connected to the first input terminal, the second input terminal, resistor R8, and the negative electrode of diode D1. The positive electrode of diode D1 and the other end of resistor R8 are commonly grounded. The other end of resistor R7 is respectively electrically connected to the first input terminal, the second input terminal, and capacitor C4 of NAND gate U3. The other end of capacitor C4 is grounded. The output terminal of NAND gate U3 is respectively electrically connected to the first input terminal of NAND gate U5 and the other output terminal of the signal failure protection module. The output terminal of NAND gate U5 is electrically connected to the input terminal of the signal-to-analog voltage module. The other end of resistor R6 is grounded.

[0015] Based on the above technical solutions, preferably, the signal-to-analog voltage module includes a conversion analog unit and a secondary filtering unit. Among them, the effective output terminal of the signal failure protection module is electrically connected to the input terminal of the conversion analog unit, which is used to convert the PWM signal into a DC reference voltage. The input terminal of the secondary filtering unit is electrically connected to the output terminal of the conversion analog unit, which is used to filter and output the converted DC reference voltage.

[0016] Based on the above technical solutions, preferably, the conversion simulation unit includes resistor R9, resistor R10, resistor R11, capacitor C5, adjustable precision voltage reference U6, and triode Q2. Among them, the output terminal of NAND gate U5 is electrically connected to resistor R10 and resistor R9 respectively. The other end of resistor R10 is electrically connected to the base of triode Q2. The collector of triode Q2 is electrically connected to the negative electrode and reference terminal of adjustable precision voltage reference U6, resistor R11, and the input terminal of the secondary filtering unit respectively. The other end of resistor R11 is electrically connected to the external power supply and capacitor C5 respectively. The other end of capacitor C5 is grounded. Resistor R9 is electrically connected to the emitter of triode Q2 and the positive electrode of adjustable precision voltage reference U6, and is commonly grounded.

[0017] Based on the above technical solutions, preferably, the secondary filtering unit includes resistor R12, resistor R13, capacitor C6, and capacitor C7. Among them, resistor R12 is electrically connected to the input terminal of the secondary filtering unit. The other end of resistor R12 is electrically connected to resistor R13 and capacitor C6 respectively. The other end of resistor R13 is electrically connected to the input terminal of the conversion simulation unit and capacitor C7 respectively. The other end of capacitor C7 is electrically connected to the other end of capacitor C7 and is commonly grounded.

[0018] Based on the above technical solutions, preferably, the model of optocoupler U1 is 6N136-X006.

[0019] The isolation voltage regulating reference circuit with failure protection of the present utility model has the following beneficial effects compared with the prior art:

[0020] (1) Through the collaborative work of the signal isolation transmission module, signal failure protection module, and signal to analog voltage module set, the problems that the PWM signal transmission in communication base stations is vulnerable to interference and there is no backup solution in case of faults are effectively solved, ensuring that the rectifier module can provide stable and reliable DC power under different working conditions, and enhancing the stability and reliability of the communication network;

[0021] (2) The filtering unit set filters the PWM input signal to remove the noise and interference in the PWM signal, ensuring the purity of the signal; the isolation unit set isolates and transmits the filtered PWM input signal to prevent electrical interference and signal crosstalk between circuits, improving the anti-interference ability of the circuit. The amplification unit set amplifies the isolated PWM input signal to ensure the strength and stability of the signal, providing a reliable signal guarantee for the normal operation of the subsequent circuit;

[0022] (3) The conversion analog unit realizes the conversion of the PWM signal to the modulation voltage through the combination of resistor voltage division, triode modulation, and a controllable precision voltage regulator; the secondary filtering unit further smooths and stabilizes the output voltage through resistor voltage division and capacitor filtering; the two cooperate to achieve the conversion from the PWM signal to a stable DC reference voltage, meeting the requirements of the communication base station switching power supply system for voltage stability. Brief Description of the Drawings

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Figure 1 It is the system module block diagram of the isolated voltage regulating reference circuit with failure protection of the present invention;

[0025] Figure 2 It is the system unit block diagram of the isolated voltage regulating reference circuit with failure protection of the present invention;

[0026] Figure 3 It is the circuit schematic diagram of the signal isolation transmission module of the isolated voltage regulating reference circuit with failure protection of the present invention;

[0027] Figure 4 It is the circuit schematic diagram of the signal failure protection module of the isolated voltage regulating reference circuit with failure protection of the present invention;

[0028] Figure 5 It is the circuit schematic diagram of the signal to analog voltage conversion module of the isolated voltage regulating reference circuit with failure protection of the present invention. Detailed Embodiments

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in combination with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0030] Such as Figure 1As shown in the figure, an isolation voltage regulating reference circuit with failure protection of the present utility model includes a signal isolation and transmission module 1, a signal failure protection module 2, and a signal-to-analog voltage module 3. Among them, the input end of the signal isolation and transmission module 1 is electrically connected to the output end of the monitoring module PWM, and is used for isolating and amplifying the PWM signal; the input end of the signal failure protection module 2 is electrically connected to the output end of the signal isolation and transmission module 1, and is used for monitoring whether the PWM signal is normal; the input end of the signal-to-analog voltage module 3 is electrically connected to the output end of the signal failure protection module 2, and is used for converting and filtering the PWM signal into a DC reference voltage.

[0031] It should be noted that by setting the signal isolation and transmission module 1, the signal failure protection module 2, and the signal-to-analog voltage module 3, it can be ensured that in a complex communication base station environment, the rectification module can receive a stable and reliable PWM signal, and provide a default voltage output when the PWM signal fails; the signal isolation and transmission module 1 isolates and amplifies the PWM signal output by the monitoring module PWM to ensure that the signal is not interfered by the outside world during the transmission process, so as to improve the transmission efficiency and stability of the signal. The signal failure protection module 2 is responsible for monitoring whether the PWM signal transmitted from the signal isolation and transmission module is normal. If it detects that the PWM signal fails, it immediately generates a trigger signal and notifies the rectification module to output according to the default voltage, so that even if a fault occurs in the PWM signal transmission, the rectification module can still maintain a stable voltage output to ensure the normal operation of the communication equipment. When the PWM signal is normal, the signal-to-analog voltage module 3 converts it into a weak DC reference voltage, and the converted DC reference voltage serves as the reference for voltage regulation inside the rectification module, thereby ensuring the stability and accuracy of the output voltage.

[0032] According to the collaborative work of the signal isolation and transmission module 1, the signal failure protection module 2, and the signal-to-analog voltage module 3 in this embodiment, the problems that the PWM signal transmission in the communication base station is vulnerable to interference and there is no backup solution in case of failure are effectively solved, ensuring that the rectification module can provide a stable and reliable DC power supply under different working conditions, and enhancing the stability and reliability of the communication network.

[0033] As Figure 2 and Figure 3 shown, the signal isolation and transmission module 1 in this embodiment includes a filtering unit 11, an isolation unit 12, and an amplifying unit 13. Among them, the input end of the filtering unit 11 is electrically connected to the output end of the monitoring module PWM, and is used for filtering the PWM input signal; the input end of the isolation unit 12 is electrically connected to the output end of the filtering unit 11, and is used for isolating and transmitting the filtered PWM input signal; the input end of the amplifying unit 13 is electrically connected to the output end of the isolation unit 12, and is used for amplifying the isolated PWM input signal.

[0034] It should be noted that the PWM input signal is filtered by the set filtering unit 11 to remove the noise and interference in the PWM signal, ensuring the purity of the signal; the filtered PWM input signal is isolated and transmitted by the set isolation unit 12 to prevent electrical interference and signal crosstalk between circuits, improving the anti-interference ability of the circuit. The isolated PWM input signal is amplified by the set amplification unit 13 to ensure the strength and stability of the signal, providing a reliable signal guarantee for the normal operation of the subsequent circuit.

[0035] As a preferred implementation manner, the signal isolation and transmission module 1 in this embodiment includes a resistor R1 and a capacitor C1. Among them, the output end of the monitoring module PWM is electrically connected to the resistor R1, the common end of the monitoring module PWM is electrically connected to the capacitor C1 and the negative electrode of the input end of the isolation unit 12 respectively, and the other end of the capacitor C1 is electrically connected to the other end of the resistor R1 and the positive electrode of the input end of the isolation unit 12 respectively.

[0036] It should be noted that the resistor R1 and the capacitor C1 form an RC filtering circuit to filter the PWM input signal to remove high-frequency noise and interference.

[0037] As a preferred implementation manner, the isolation unit 12 in this embodiment includes an optocoupler U1, a resistor R3 and a resistor R4. Among them, pin 2 of the optocoupler U1 serves as the positive electrode of the input end of the isolation unit 12, pin 3 of the optocoupler U1 serves as the negative electrode of the input end of the isolation unit 12, pins 6 and 8 of the optocoupler U1 are commonly electrically connected to the resistor R4, pin 7 of the optocoupler U1 is electrically connected to the resistor R3, and the other end of the resistor R3 is electrically connected to pin 5 of the optocoupler U1.

[0038] Specifically, the model of the optocoupler U1 in this embodiment is 6N136-X006.

[0039] It should be noted that when the PWM signal is input to pins 2 and 3 of the optocoupler U1, the LED inside the optocoupler emits light, causing the photosensitive transistor to conduct; a path is formed between pin 7 and pin 6 of the optocoupler, and the PWM signal is isolated and transmitted to the subsequent circuit; the resistors R3 and R4 jointly provide the necessary static operating point and current limit for the optocoupler to ensure the stable transmission of the PWM signal and the reliable operation of the optocoupler.

[0040] As a preferred embodiment, the amplification unit 13 in this embodiment includes a resistor R2, a resistor R5, and a triode Q1. Among them, the common connection of pin 6 and pin 8 of the optocoupler U1 is also electrically connected to the resistor R2. The other end of the resistor R2 is electrically connected to the base of the triode Q1. The emitter of the triode Q1 is electrically connected to the common terminal of pin 5 of the optocoupler U1 and the resistor R3 and is grounded. The collector of the triode Q1 is respectively electrically connected to the resistor R5 and the output end of the signal isolation and transmission module 1. The other end of the resistor R5 is respectively electrically connected to the other end of the capacitor C2 and the resistor R4, and is connected to an external power supply; the other end of the capacitor C2 is grounded.

[0041] It should be noted that when the optocoupler U1 receives the input PWM signal, the light-emitting diode inside it will emit light and drive the photosensitive triode to conduct or cut off; the common terminal of pin 6 and pin 8 of the optocoupler U1 will output a current signal corresponding to the input PWM signal. This current signal is converted into a voltage signal after passing through the resistor R2 and is input to the base of the triode Q1; when the base voltage is high enough, the triode Q1 will conduct, thereby amplifying the input signal and outputting it to the collector. The amplified signal output by the collector is limited in current by the resistor R5, and then filtered by the capacitor C2 to remove high-frequency noise and interference signals, and finally a stable and amplified PWM signal is output to the output end of the signal isolation and transmission module 1, realizing the amplification function of the PWM signal.

[0042] As Figure 4 shown, as a preferred embodiment, the signal failure protection module 2 in this embodiment includes resistors R6, R7, R8, capacitors C3, C4, a diode D1, and NAND gates U2, U3, U4, U5. Among them, the output end of the signal isolation and transmission module 1 is electrically connected to the resistor R6, the second input end of the NAND gate U5, and the first input end of the NAND gate U4. The second input end of the NAND gate U4 is respectively electrically connected to the output end of the NAND gate U2 and the resistor R7. The output end of the NAND gate U4 is electrically connected to the capacitor C3. The other end of the capacitor C3 is respectively electrically connected to the first input end, the second input end, the resistor R8, and the negative pole of the diode D1 of the NAND gate U4. The positive pole of the diode D1 and the other end of the resistor R8 are commonly grounded. The other end of the resistor R7 is respectively electrically connected to the first input end, the second input end, and the capacitor C4 of the NAND gate U3. The other end of the capacitor C4 is grounded. The output end of the NAND gate U3 is respectively electrically connected to the first input end of the NAND gate U5 and the other output end of the signal failure protection module 2. The output end of the NAND gate U5 is electrically connected to the input end of the signal-to-analog voltage module 3. The other end of the resistor R6 is grounded.

[0043] Specifically, the models of the NAND gates U2, U3, U4, and U5 in this embodiment are all CD4093.

[0044] It should be noted that the monitoring unit sends a PWM signal to the signal isolation and transmission module 1. The signal isolation and transmission module 1 isolates and amplifies the PWM signal and then transmits it to the resistor R6 of the signal failure protection module 2. The PWM signal enters the second input terminal of the NAND gate U5 through the resistor R6 and simultaneously enters the first input terminal of the NAND gate U4. If the PWM signal is normal, the output terminal of the NAND gate U4 will not be triggered. If the PWM signal fails, the level of the output terminal of the NAND gate U4 will change. When the NAND gate U4 is triggered, the circuit composed of the capacitor C3, the resistor R8, and the diode D1 will further process the trigger signal. At the same time, the logic circuit composed of the NAND gates U2 and U3 will also output a corresponding PWM-FAIL trigger signal according to the failure situation of the PWM signal. The PWM-FAIL signal can be used for the processing of other external circuits, such as physically disconnecting or closing a relay, etc., to achieve more perfect protection. If the PWM signal is normal, the signal conversion to analog voltage module 3 will output a weak DC reference voltage according to this signal as the reference for voltage regulation inside the rectification module. If the PWM signal fails, the signal conversion to analog voltage module 3 may output a default voltage value.

[0045] According to this embodiment, the signal failure protection module 2 is set to implement the failure detection and protection function of the PWM signal, ensuring that the rectification module can output according to the default voltage when the PWM signal fails, thereby guaranteeing the stability and reliability of the communication power supply system.

[0046] Such as Figure 2 and Figure 5 As shown, as a preferred embodiment, the signal conversion to analog voltage module 3 in this embodiment includes a conversion analog unit 31 and a secondary filtering unit 32. Among them, the effective output terminal of the signal failure protection module 2 is electrically connected to the input terminal of the conversion analog unit 31 for converting the PWM signal into a DC reference voltage. The input terminal of the secondary filtering unit 32 is electrically connected to the output terminal of the conversion analog unit 31 for filtering and outputting the converted DC reference voltage.

[0047] It should be noted that the effective PWM signal from the signal failure protection module 2 is converted into a DC reference voltage, and the DC reference voltage output by the conversion analog unit 31 is further filtered to output an accurate and stable voltage reference, so as to meet the voltage regulation inside the rectification module.

[0048] As a preferred embodiment, the conversion simulation unit 31 in this embodiment includes a resistor R9, a resistor R10, a resistor R11, a capacitor C5, a precision voltage regulator U6, and a triode Q2. Among them, the output terminals of the NAND gate U5 are electrically connected to the resistor R10 and the resistor R9 respectively. The other end of the resistor R10 is electrically connected to the base of the triode Q2. The collector of the triode Q2 is electrically connected to the negative electrode and the reference terminal of the precision voltage regulator U6, the resistor R11, and the input terminal of the secondary filtering unit 32 respectively. The other end of the resistor R11 is electrically connected to the external power supply and the capacitor C5 respectively. The other end of the capacitor C5 is grounded. The resistor R9 is electrically connected to the emitter of the triode Q2 and the positive electrode of the precision voltage regulator U6, and is commonly grounded.

[0049] It should be noted that the effective output PWM signal processed by the signal failure protection module 2 is sent to the output terminal of the NAND gate U5. When the PWM signal is normal, the NAND gate U5 outputs a corresponding logic level. This level is sent to the base of the triode Q2 after being divided by the resistors R10 and R9. When the base receives an appropriate voltage, the triode Q2 enters the amplification state, and its collector current changes. The precision voltage regulator U6 adjusts its output voltage according to the change of the collector current of the triode Q2 to maintain a stable DC reference voltage. The conversion simulation unit 31 realizes the efficient conversion of the PWM signal to the DC reference voltage by combining the analog circuit and the digital logic circuit. This unit not only has high stability and accuracy, but also can adapt to complex working environments, providing reliable reference voltage support for the entire power supply system.

[0050] As a preferred embodiment, the secondary filtering unit 32 in this embodiment includes a resistor R12, a resistor R13, a capacitor C6, and a capacitor C7. Among them, the resistor R12 is electrically connected to the input terminal of the secondary filtering unit 32. The other end of the resistor R12 is electrically connected to the resistor R13 and the capacitor C6 respectively. The other end of the resistor R13 is electrically connected to the input terminal of the conversion simulation unit 31 and the capacitor C7 respectively. The other end of the capacitor C7 is electrically connected to the other end of the capacitor C7 and is commonly grounded.

[0051] It should be noted that the modulation voltage transmitted from the conversion simulation unit 31 first passes through the voltage division of the resistors R12 and R13. The voltage after voltage division then passes through the secondary filtering circuit composed of the capacitors C6 and C7 to further smooth and stabilize the output voltage. The capacitors C6 and C7 filter out the high-frequency noise and ripple in the voltage through the charge and discharge effect, ensuring the stability and accuracy of the output voltage.

[0052] According to this embodiment, the conversion simulation unit 31 realizes the conversion from the PWM signal to the modulation voltage through the combination of resistor voltage division, triode modulation, and a precision regulated voltage source; the secondary filtering unit 32 further smooths and stabilizes the output voltage through resistor voltage division and capacitor filtering; the two work together to realize the conversion from the PWM signal to a stable DC reference voltage, meeting the requirements of the communication base station switching power supply system for voltage stability.

[0053] Working principle:

[0054] The signal isolation and transmission module 1 includes an optocoupler U1, a triode Q1, and resistors R1, R2, R3, R4, R5, and capacitors C1, C2; R1 and C1 form an RC filter circuit to filter the PWM input signal and then enter the optocoupler U1 for isolation transmission. R3 and R4 provide a quiescent operating point for the optocoupler U1; the resistors R2, R5, and the triode Q1 play an amplifying role; C2 filters the power supply, and thus filters, isolates, and amplifies the PWM input signal.

[0055] The signal failure protection module 2 includes resistors R6, R7, R8, capacitors C3, C4, a diode D1, and NAND gates U2, U3, U4, U5. After the PWM input signal is filtered, isolated, and amplified, it is input by U5. At the same time, the signal is transmitted to the trigger circuit composed of the diode D1, resistors R7, R8, capacitors C3, C4, and NAND gates U4, U2, U3. After being processed by the trigger circuit, it is output to the second input terminal of the NAND gate U5 for logical processing and outputs a PWM-FAIL signal for other external circuits to process.

[0056] The signal-to-analog voltage module 3 includes a precision regulated voltage source U6, a triode Q2, and resistors R9, R10, R11, R12, R13, and capacitors C5, C6, C7. The resistors R9, R10, R11 provide a quiescent operating point for the triode Q2. The triode Q2 plays an amplifying role and modulates the voltage of the precision regulated voltage source U6. After secondary filtering by the resistors R12, R13, and capacitors C6, C7, an accurate voltage reference is output.

[0057] The above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An isolation voltage regulating reference circuit with failure protection, characterized in that, Comprising: A signal isolation and transmission module (1), a signal failure protection module (2), and a signal-to-analog voltage module (3), wherein The input end of the signal isolation and transmission module (1) is electrically connected to the output end of the monitoring module PWM, and is used for isolating and amplifying the PWM signal; The input end of the signal failure protection module (2) is electrically connected to the output end of the signal isolation and transmission module (1), and is used for monitoring whether the PWM signal is normal; The input end of the signal-to-analog voltage module (3) is electrically connected to the output end of the signal failure protection module (2), and is used for converting and filtering the PWM signal into a DC reference voltage.

2. The isolation voltage regulating reference circuit with fail-safe protection according to claim 1, characterized in that: The signal isolation and transmission module (1) includes a filtering unit (11), an isolation unit (12), and an amplifying unit (13), wherein the input end of the filtering unit (11) is electrically connected to the output end of the monitoring module PWM, and is used for filtering the PWM input signal; the input end of the isolation unit (12) is electrically connected to the output end of the filtering unit (11), and is used for isolating and transmitting the filtered PWM input signal; the input end of the amplifying unit (13) is electrically connected to the output end of the isolation unit (12), and is used for amplifying the isolated PWM input signal.

3. The isolation voltage regulating reference circuit with fail-safe protection according to claim 2, wherein: The signal isolation and transmission module (1) includes a resistor R1 and a capacitor C1, wherein the output end of the monitoring module PWM is electrically connected to the resistor R1, the common end of the monitoring module PWM is electrically connected to the capacitor C1 and the negative electrode of the input end of the isolation unit (12) respectively, and the other end of the capacitor C1 is electrically connected to the other end of the resistor R1 and the positive electrode of the input end of the isolation unit (12) respectively.

4. The isolation voltage regulating reference circuit with fail-safe protection according to claim 3, wherein: The isolation unit (12) includes an optocoupler U1, a resistor R3, and a resistor R4, wherein the pin 2 of the optocoupler U1 serves as the positive electrode of the input end of the isolation unit (12), the pin 3 of the optocoupler U1 serves as the negative electrode of the input end of the isolation unit (12), the pins 6 and 8 of the optocoupler U1 are commonly electrically connected to the resistor R4, the pin 7 of the optocoupler U1 is electrically connected to the resistor R3, and the other end of the resistor R3 is electrically connected to the pin 5 of the optocoupler U1.

5. The isolation voltage regulating reference circuit with fail-safe protection according to claim 4, characterized in that: The amplifying unit (13) includes a resistor R2, a resistor R5, and a triode Q1, wherein the pins 6 and 8 of the optocoupler U1 are also commonly electrically connected to the resistor R2, the other end of the resistor R2 is electrically connected to the base of the triode Q1, the emitter of the triode Q1 is electrically connected to the common end of the pin 5 of the optocoupler U1 and the resistor R3 and grounded, the collector of the triode Q1 is electrically connected to the resistor R5 and the output end of the signal isolation and transmission module (1) respectively, the other end of the resistor R5 is electrically connected to the capacitor C2 and the other end of the resistor R4 respectively, and is connected to an external power supply; the other end of the capacitor C2 is grounded.

6. The isolation voltage regulating reference circuit with fail-safe protection according to claim 5, characterized in that: The signal failure protection module (2) includes resistors R6, R7, R8, capacitors C3, C4, diode D1, and NAND gates U2, U3, U4, U5. Among them, the output terminal of the signal isolation and transmission module (1) is electrically connected to resistor R6, the second input terminal of NAND gate U5, and the first input terminal of NAND gate U4. The second input terminal of NAND gate U4 is respectively electrically connected to the output terminal of NAND gate U2 and resistor R7. The output terminal of NAND gate U4 is electrically connected to capacitor C3. The other end of capacitor C3 is respectively electrically connected to the first input terminal, the second input terminal of NAND gate U4, resistor R8, and the negative electrode of diode D1. The positive electrode of diode D1 and the other end of resistor R8 are commonly grounded. The other end of resistor R7 is respectively electrically connected to the first input terminal, the second input terminal of NAND gate U3, and capacitor C4. The other end of capacitor C4 is grounded. The output terminal of NAND gate U3 is respectively electrically connected to the first input terminal of NAND gate U5 and the other output terminal of the signal failure protection module (2). The output terminal of NAND gate U5 is electrically connected to the input terminal of the signal-to-analog voltage module (3). The other end of resistor R6 is grounded.

7. The isolation voltage regulating reference circuit with fail-safe protection according to claim 6, characterized in that: The signal-to-analog voltage module (3) includes a conversion analog unit (31) and a secondary filtering unit (32). Among them, the effective output terminal of the signal failure protection module (2) is electrically connected to the input terminal of the conversion analog unit (31), which is used to convert the PWM signal into a DC reference voltage. The input terminal of the secondary filtering unit (32) is electrically connected to the output terminal of the conversion analog unit (31), which is used to filter and output the converted DC reference voltage.

8. The isolation voltage regulating reference circuit with fail-safe protection according to claim 7, characterized in that: The conversion analog unit (31) includes resistors R9, R10, R11, capacitor C5, a precision voltage regulator U6, and transistor Q2. Among them, the output terminal of NAND gate U5 is respectively electrically connected to resistor R10 and resistor R9. The other end of resistor R10 is electrically connected to the base of transistor Q2. The collector of transistor Q2 is respectively electrically connected to the negative electrode and the reference terminal of the precision voltage regulator U6, resistor R11, and the input terminal of the secondary filtering unit (32). The other end of resistor R11 is respectively electrically connected to an external power supply and capacitor C5. The other end of capacitor C5 is grounded. Resistor R9 is electrically connected to the emitter of transistor Q2 and the positive electrode of the precision voltage regulator U6, and they are commonly grounded.

9. The isolation voltage regulating reference circuit with fail-safe protection according to claim 8, characterized in that: The secondary filtering unit (32) includes resistors R12, R13, capacitors C6, and C7. Among them, resistor R12 is electrically connected to the input terminal of the secondary filtering unit (32). The other end of resistor R12 is respectively electrically connected to resistor R13 and capacitor C6. The other end of resistor R13 is respectively electrically connected to the input terminal of the conversion analog unit (31) and capacitor C7. The other end of capacitor C7 is electrically connected to the other end of capacitor C7 and is commonly grounded.

10. The isolation voltage regulating reference circuit with fail-safe protection according to claim 4, characterized in that: The model of the optocoupler U1 is 6N136-X006.

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