Configurable integrated voltage regulator circuit and terminal unit for dc carrier bus power harvesting

Abstract

The application relates to a configurable integrated voltage stabilizing circuit and a terminal unit for direct current carrier bus power taking, wherein the configurable integrated voltage stabilizing circuit comprises a reference module for generating a reference voltage; and a voltage stabilizing and current stabilizing module connected with an output end of the reference module, which adopts a structure of double amplifiers, a current mirror and an adjusting tube to realize voltage stabilization and current limitation. The application can realize reliable power taking and voltage output of the direct current carrier bus.

Description

Technical Field

[0001] This invention relates to the fields of integrated circuit design, analog signal processing, and bus communication technology, and in particular to a configurable integrated voltage regulator circuit and terminal unit powered by a DC carrier bus. Background Technology

[0002] DC-DC carrier bus communication systems are widely used in industrial control and communication, such as in smart buildings, mining sites, and industrial and home control equipment. This communication method typically... Figure 1 As shown, the two buses wire1 and wire2 serve as both power lines and signal lines, and simultaneously carry multiple terminal units (T1, T2, T3...Tn) to achieve one-to-many bidirectional communication.

[0003] like Figure 2 As shown, each terminal unit (Tn) typically includes two internal modules: power management and bus transceiver, which respectively implement bus power supply and data communication functions. The power management module needs to obtain a stable DC regulated power supply (represented by Vcc in the diagram) from the DC carrier signal of the bus carrying communication data, to power the bus transceiver module. The module's power supply VDD and ground Gnd ports are connected to bus wire1 and bus wire2 respectively, outputting a low-voltage power supply Vcc, which, after connecting to the filter capacitor Cload, is used to power the bus transceiver module.

[0004] However, the terminal unit needs to support hot-swapping. Due to the presence of the internal filter capacitor Cload in the terminal unit (Tn), when a new terminal unit is connected while the bus system is operating, the charging of the filter capacitor Cload will cause a large instantaneous current on the bus, which may lead to communication protocol failure. To solve this problem, the power management module needs to perform current limiting on the charging of the filter capacitor Cload, and the threshold can be set by an external resistor to suit the requirements of different situations. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a configurable integrated voltage regulator circuit and terminal unit for DC carrier bus power supply, which can realize reliable power supply and voltage regulation output of DC carrier bus.

[0006] The technical solution adopted by this invention to solve its technical problem is: to provide a configurable integrated voltage regulator circuit for DC carrier bus power supply, comprising:

[0007] The reference module is used to generate a reference voltage.

[0008] The voltage and current stabilization module is connected to the output of the reference module and adopts an architecture of dual amplifiers, current mirror and regulating tube to achieve voltage stabilization and current limiting.

[0009] The voltage and current regulation module includes a first amplifier, a second amplifier, a first MOSFET, a second MOSFET, and a regulating transistor;

[0010] The gates of the first MOSFET and the source of the second MOSFET are connected together to form a current mirror.

[0011] The inverting input terminal of the first amplifier is connected to the output terminal of the reference module, the non-inverting input terminal is connected to the drain of the second MOS transistor, and the output terminal is connected to the gate of the first MOS transistor.

[0012] The inverting input terminal of the second amplifier is connected to the output terminal of the reference module, the non-inverting input terminal is connected to the drain of the regulating transistor, and the output terminal is connected to the gate of the regulating transistor.

[0013] The source of the first MOS transistor is connected to the power supply terminal, and the drain is connected to the source of the regulating transistor.

[0014] The drain of the second MOS transistor is connected to an external configuration resistor as a resistor configuration port; the drain of the adjustment transistor is connected to an external filter capacitor as an output power supply port.

[0015] The maximum current output by the power supply port is: ,in, The mirror ratio of the current mirror is given. As the reference voltage, The resistance value of the externally configured resistor.

[0016] The reference module includes a voltage divider section, an adjustment section, and a filtering section connected in sequence.

[0017] The voltage divider section is used to clamp the voltage output from the power supply terminal to a fixed voltage;

[0018] The adjustment section is used to generate a reference voltage based on the fixed voltage;

[0019] The filtering section is used to filter out interference signals in the reference voltage.

[0020] The voltage divider section includes a voltage divider resistor and a Zener diode. One end of the voltage divider resistor is connected to the power supply terminal, and the other end is connected to the negative terminal of the Zener diode, while the positive terminal of the Zener diode is grounded. The other end of the voltage divider resistor is also connected to the input terminal of the adjustment section.

[0021] The adjustment section includes a rectifier diode and a discharge resistor. The positive terminal of the rectifier diode is connected to the output terminal of the voltage divider section, and the negative terminal is connected to the input terminal of the filter section. One end of the discharge resistor is connected to the negative terminal of the rectifier diode, and the other end is grounded.

[0022] The filtering section is an RC filter circuit, and the time constant of the RC filter circuit is less than the time constant of the RC network composed of the external load and the external filter capacitor.

[0023] The resistance values ​​of the voltage divider resistor and the discharge resistor satisfy the following: ,in, The voltage at the power supply terminal. This is the reverse breakdown voltage of the Zener diode. The reference voltage is represented as: , This is the forward conduction voltage of the rectifier diode. This is the resistance value of the voltage divider resistor. This is the resistance value of the discharge resistor. and These are the minimum regulated current and the maximum allowable operating current of the Zener diode, respectively.

[0024] The technical solution adopted by this invention to solve its technical problem is as follows: A terminal unit is provided, including a power management section, a bus transceiver section, a configuration resistor, and a filter capacitor. The power management section includes a configurable integrated voltage regulator circuit for powering a DC carrier bus, wherein the resistor configuration port of the configurable integrated voltage regulator circuit is connected to one end of the configuration resistor, and the output power supply port is connected to one end of the filter capacitor and the bus transceiver section respectively. The power supply terminals of both the power management section and the bus transceiver section are connected to the positive terminal of the bus signal, and the ground terminal is connected to the negative terminal of the bus signal. The other end of the configuration resistor and the other end of the filter capacitor are both connected to the negative terminal of the bus signal.

[0025] Beneficial effects

[0026] By adopting the above-mentioned technical solution, this invention has the following advantages and positive effects compared with the prior art: This invention can directly draw power from the DC carrier bus, generate a stable reference voltage through the reference module, and simultaneously achieve high-precision output voltage regulation and power-on current limiting control based on the dual amplifier, current mirror, and regulating transistor architecture of the voltage and current regulating module. This invention can output a stable low voltage to power the terminal load and effectively suppress inrush current during terminal hot-plugging, avoiding instantaneous voltage drops on the bus and ensuring the communication stability of other terminals on the bus. Furthermore, the current limiting threshold of this invention can be flexibly configured through external resistors to adapt to different bus load scenarios. It also features high circuit integration and fewer external components, reducing terminal size and material costs. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the bus connection method in a DC carrier bus communication system in the prior art;

[0028] Figure 2 This is a schematic diagram of the terminal unit;

[0029] Figure 3 This is a circuit diagram of a configurable integrated voltage regulator circuit powered by a DC carrier bus according to the first embodiment of the present invention. Detailed Implementation

[0030] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0031] The first embodiment of the present invention relates to a configurable integrated voltage regulator circuit powered by a DC carrier bus, such as... Figure 3 As shown, it includes:

[0032] The reference module is used to generate a reference voltage.

[0033] The voltage and current stabilization module is connected to the output of the reference module and adopts an architecture of dual amplifiers, current mirror and regulating tube to achieve voltage stabilization and current limiting.

[0034] In this embodiment, the voltage and current regulation module includes a first amplifier AMP1, a second amplifier AMP2, a first MOSFET M1, a second MOSFET M2, and a regulating transistor M3. The gates and sources of the first MOSFET M1 and the second MOSFET M2 are connected, forming a current mirror. The inverting input of the first amplifier AMP1 is connected to the output of the reference module, the non-inverting input is connected to the drain of the second MOSFET M2, and the output is connected to the gate of the first MOSFET M1. The inverting input of the second amplifier AMP2 is connected to the output of the reference module, the non-inverting input is connected to the drain of the regulating transistor M3, and the output is connected to the gate of the regulating transistor M3. The source of the first MOSFET M1 is connected to the power supply terminal VDD, and the drain is connected to the source of the regulating transistor M3. The drain of the second MOSFET M2 serves as a resistor configuration port Set, connected to an external configuration resistor R. Set Connected; the drain of the regulating transistor M3 serves as the output power supply port VCC and is connected to the external filter capacitor C. load Connected.

[0035] In this embodiment, the first MOSFET M1 and the second MOSFET M2 form a current mirror relationship. Assume the mirror ratio of the first MOSFET M1 and the second MOSFET M2 is... Therefore, the maximum charging current I of the external filter capacitor Cload is limited to Among them, the mirror ratio The ratio of the drain currents of the first MOSFET M1 and the second MOSFET M2 is determined by the process dimensions of the MOSFETs (width-to-length ratio W / L). As the reference voltage, Configure external resistor R Set The resistance value shows that the maximum value of the charging current can be limited simply by adjusting the external configuration resistor.

[0036] The reference module in this embodiment includes a voltage divider section, an adjustment section, and a filtering section connected in sequence; wherein, the voltage divider section is used to clamp the voltage output from the power supply terminal to a fixed voltage; the adjustment section is used to generate a reference voltage based on the fixed voltage; and the filtering section is used to filter out interference signals in the reference voltage.

[0037] The voltage divider section in this embodiment includes a voltage divider resistor R1 and a Zener diode D1. One end of the voltage divider resistor R1 is connected to the power supply terminal VDD, and the other end is connected to the negative terminal of the Zener diode D1, while the positive terminal of the Zener diode D1 is grounded. The other end of the voltage divider resistor R1 is also connected to the input terminal of the adjustment section.

[0038] The adjustment section in this embodiment includes a rectifier diode D2 and a discharge resistor R2. The positive terminal of the rectifier diode D2 is connected to the output terminal of the voltage divider section (i.e., the other end of the voltage divider resistor R1), and the negative terminal is connected to the input terminal of the filter section. One end of the discharge resistor R2 is connected to the negative terminal of the rectifier diode D2, and the other end is grounded.

[0039] The filtering section in this embodiment is an RC filter circuit, which includes a filter resistor R3 and a filter capacitor C1. One end of the filter resistor R3 is connected to the output terminal of the adjustment section (i.e., the negative terminal of the rectifier diode D2), and the other end serves as the output terminal of the reference module. One end of the filter capacitor C1 is connected to the other end of the filter resistor R3, and the other end is grounded. It is worth mentioning that the time constant of the RC filter circuit in this embodiment is less than that of the external load R. load and external filter capacitor C load The time constant of the constructed RC network.

[0040] Assume the voltage at the power supply terminal VDD is The reverse breakdown voltage of Zener diode D1 is The forward conduction voltage of rectifier diode D2 is Then the reference voltage can be expressed as To ensure the reference module can generate a reference voltage, the values ​​of the voltage divider resistor R1 and the discharge resistor R2 must meet the following requirements: ,in, and These are the minimum regulated current and the maximum allowable operating current of the Zener diode, respectively.

[0041] The second embodiment of the present invention relates to a terminal unit, including a power management section, a bus transceiver section, a configuration resistor, and a filter capacitor; the power management section includes a configurable integrated voltage regulator circuit for drawing power from a DC carrier bus as described in the first embodiment, wherein the resistor configuration port of the configurable integrated voltage regulator circuit is connected to one end of the configuration resistor, and the output power supply port is connected to one end of the filter capacitor and the bus transceiver section respectively; the power supply terminals of the power management section and the bus transceiver section are both connected to the positive terminal of the bus signal, and the ground terminal is connected to the negative terminal of the bus signal; the other end of the configuration resistor and the other end of the filter capacitor are both connected to the negative terminal of the bus signal.

[0042] The working principle of this implementation method is as follows:

[0043] When a terminal unit is connected to the bus as a new terminal, the power management section is in the power-on initialization state. At this time, the filter capacitor C1 and the external filter capacitor C load Charging begins. Because the time constant of the RC network formed by filter resistor R3 and filter capacitor C1 is less than that of the external load R... load and external filter capacitor C load Due to the time constant of the RC network, the voltage at the output of the reference module will first reach the predetermined voltage value, becoming the reference voltage V1. The reference module obtains the reference voltage from the bus through a voltage divider resistor R1 and a Zener diode D1, then through a rectifier diode D2 and a discharge resistor R2, and finally through a low-pass filter composed of a filter resistor R3 and a filter capacitor C1 to obtain a reference voltage V1.

[0044] The first amplifier AMP1 is used to configure the maximum charging current. Its output simultaneously drives the first MOSFET M1 and the second MOSFET M2, such that the drain current of the second MOSFET M2 is within the configuration resistor R. Set A voltage V is formed on it. rset Furthermore, under the feedback amplification mechanism of the first amplifier AMP1, the voltage V... rset It is equal to the reference voltage V1. Since the first MOSFET M1 and the second MOSFET M2 form a current mirror relationship, assuming their current mirror ratio is K, the maximum drain current I of the first MOSFET M1 is... m1 Restricted to: .

[0045] The second amplifier, AMP2, is used for output voltage regulation control. This is due to the external filter capacitor C. loadThe capacitance value is relatively large, and its voltage VCC rise time is the slowest. Before the voltage reaches the reference voltage V1, the second amplifier AMP2 will output a low level, pulling the gate of the regulating transistor M3 low and causing M3 to conduct. Since the regulating transistor M3 is connected in series with the first MOSFET M1, its drain current is affected by I... m1 The limitation is that it is therefore restricted to a maximum of I. m1 The range. When the external filter capacitor C... load The voltage VCC continues to rise until it approaches the reference voltage V1. Under the feedback mechanism of the second amplifier AMP2, the external filter capacitor C... load The voltage VCC on the circuit no longer increases, but remains approximately around the reference voltage V1, thus achieving the goal of regulated output. During this process, the external filter capacitor C... load The charging current will never exceed the maximum drain current I of the first MOSFET M1. m1 This achieves the technical goal of both voltage regulation and current limiting, without affecting the normal communication of other terminals on the bus.

[0046] It is easy to see that this invention can directly draw power from the DC carrier bus, generate a stable reference voltage through the reference module, and simultaneously achieve high-precision output voltage regulation and power-on current limiting control based on the dual amplifier, current mirror, and regulating transistor architecture of the voltage and current regulating module. This invention can output a stable low voltage to power the terminal load, and effectively suppress inrush current during terminal hot-plugging, avoiding instantaneous voltage drops on the bus and ensuring the communication stability of other terminals on the bus. Furthermore, the current limiting threshold of this invention can be flexibly configured through external resistors, thus adapting to different bus load scenarios. It also features high circuit integration and fewer external components, reducing terminal size and material costs.

Claims

1. A configurable integrated voltage regulator circuit powered by a DC carrier bus, characterized in that, include: The reference module is used to generate a reference voltage. The voltage and current stabilization module is connected to the output of the reference module and adopts an architecture of dual amplifiers, current mirror and regulating tube to achieve voltage stabilization and current limiting.

2. The configurable integrated voltage regulator circuit for DC carrier bus power supply according to claim 1, characterized in that, The voltage and current regulation module includes a first amplifier, a second amplifier, a first MOSFET, a second MOSFET, and a regulating transistor; The gates of the first MOSFET and the source of the second MOSFET are connected together to form a current mirror. The inverting input terminal of the first amplifier is connected to the output terminal of the reference module, the non-inverting input terminal is connected to the drain of the second MOS transistor, and the output terminal is connected to the gate of the first MOS transistor. The inverting input terminal of the second amplifier is connected to the output terminal of the reference module, the non-inverting input terminal is connected to the drain of the regulating transistor, and the output terminal is connected to the gate of the regulating transistor. The source of the first MOS transistor is connected to the power supply terminal, and the drain is connected to the source of the regulating transistor. The drain of the second MOS transistor is connected to an external configuration resistor as a resistor configuration port; the drain of the adjustment transistor is connected to an external filter capacitor as an output power supply port.

3. The configurable integrated voltage regulator circuit for DC carrier bus power supply according to claim 2, characterized in that, The maximum current output by the power supply port is: ,in, The mirror ratio of the current mirror is given. As the reference voltage, The resistance value of the externally configured resistor.

4. The configurable integrated voltage regulator circuit for DC carrier bus power supply according to claim 1, characterized in that, The reference module includes a voltage divider section, an adjustment section, and a filtering section connected in sequence. The voltage divider section is used to clamp the voltage output from the power supply terminal to a fixed voltage; The adjustment section is used to generate a reference voltage based on the fixed voltage; The filtering section is used to filter out interference signals in the reference voltage.

5. The configurable integrated voltage regulator circuit for DC carrier bus power supply according to claim 4, characterized in that, The voltage divider section includes a voltage divider resistor and a Zener diode. One end of the voltage divider resistor is connected to the power supply terminal, and the other end is connected to the negative terminal of the Zener diode, while the positive terminal of the Zener diode is grounded. The other end of the voltage divider resistor is also connected to the input terminal of the adjustment section.

6. The configurable integrated voltage regulator circuit for DC carrier bus power supply according to claim 5, characterized in that, The adjustment section includes a rectifier diode and a discharge resistor. The positive terminal of the rectifier diode is connected to the output terminal of the voltage divider section, and the negative terminal is connected to the input terminal of the filter section. One end of the discharge resistor is connected to the negative terminal of the rectifier diode, and the other end is grounded.

7. The configurable integrated voltage regulator circuit for DC carrier bus power supply according to claim 4, characterized in that, The filtering section is an RC filter circuit, and the time constant of the RC filter circuit is less than the time constant of the RC network composed of the external load and the external filter capacitor.

8. The configurable integrated voltage regulator circuit for DC carrier bus power supply according to claim 6, characterized in that, The resistance values ​​of the voltage divider resistor and the discharge resistor satisfy the following: ,in, The voltage at the power supply terminal. This is the reverse breakdown voltage of the Zener diode. The reference voltage is represented as: , This is the forward conduction voltage of the rectifier diode. This is the resistance value of the voltage divider resistor. This is the resistance value of the discharge resistor. and These are the minimum regulated current and the maximum allowable operating current of the Zener diode, respectively.

9. A terminal unit, characterized in that, The system includes a power management section, a bus transceiver section, a configuration resistor, and a filter capacitor. The power management section includes a configurable integrated voltage regulator circuit for drawing power from a DC carrier bus as described in any one of claims 1-8. The resistor configuration port of the configurable integrated voltage regulator circuit is connected to one end of the configuration resistor, and the output power supply port is connected to one end of the filter capacitor and the bus transceiver section, respectively. The power supply terminals of both the power management section and the bus transceiver section are connected to the positive terminal of the bus signal, and the ground terminal is connected to the negative terminal of the bus signal. The other end of the configuration resistor and the other end of the filter capacitor are both connected to the negative terminal of the bus signal.

Images