Constant current source with high control precision

Abstract

The utility model relates to power supply technical field, concretely relates to a constant current source with high control precision, including the power input module for power input and preliminary filter, the constant current output module for realizing current constant output, the main control module for overall control, the current feedback module for monitoring current, the communication module for communication and the power supply module for power supply, the output of power input module is connected with the input of constant current output module and the input of power supply module respectively, and the monitoring end of current feedback module is connected with the output of constant current output module. The utility model can realize a series of tasks such as the filtering of power supply, the constant output of current, the real -time monitoring of output current and the networking communication of constant current source, and the automation, intelligent degree is high, and the control precision is high, and the digital control is simultaneously convenient, so that constant current source has higher programmability and flexibility, is convenient to use, and has good versatility.

Description

Technical Field

[0001] This utility model relates to the field of power supply technology, specifically to a constant current source with high control precision. Background Technology

[0002] With the rapid development of electronic technology, more and more products are incorporating innovative achievements in this field, thereby greatly improving the performance indicators of related products in various industries. In this process, the quality and characteristics of power supplies, as an indispensable part of electronic devices, are particularly important. Especially in applications requiring high precision and stability, the design and implementation of power supplies have become one of the key factors affecting the performance of the entire system. Constant current sources, as a special type of power supply, have wide application needs in fields such as LED drivers, sensor power supplies, and test and measurement equipment. The accuracy and stability of their output current directly affect the performance of the end product. Under current technological trends, more and more products are moving towards digital control. This is because numerical control can provide more precise and flexible control capabilities, adapting to the complex needs of different application scenarios. In the field of numerically controlled constant current sources, traditional analog control methods are no longer sufficient to meet the requirements of modern electronic devices for high precision, small size, and intelligence. Reducing product size is difficult, power consumption is high, and it is difficult to further promote the development of various electronic devices towards miniaturization and high efficiency. Utility Model Content

[0003] The technical problem to be solved by this utility model is that the existing constant current sources have a low degree of automation and intelligence and low control precision, which makes it difficult to meet the requirements of modern electronic equipment for high precision, small size and intelligence.

[0004] To solve the above technical problems, this utility model adopts the following technical solution: a constant current source with high control precision, comprising a power input module for power input and preliminary filtering, a constant current output module for achieving constant current output, a main control module for overall control, a current feedback module for monitoring current, a communication module for communication, and a power supply module for power supply. The input terminal of the power input module is connected to the corresponding power supply interface, and the output terminal of the power input module is connected to the input terminal of the constant current output module and the input terminal of the power supply module, respectively. The monitoring terminal of the current feedback module is connected to the output terminal of the constant current output module. The power supply module supplies power to the constant current output module, the main control module, the current feedback module, and the communication module. The control terminal of the constant current output module and the signal output terminal of the current feedback module are both connected to the main control module. The main control module is connected to the corresponding communication bus through the communication module.

[0005] When this utility model is working, it can achieve a series of tasks such as power supply filtering, constant current output, real-time monitoring of output current, and network communication of constant current source. It has a high degree of automation and intelligence, high control precision, and is convenient for digital control, which makes the constant current source highly programmable and flexible, easy to use, and versatile.

[0006] Preferably, the power input module includes a rectifier bridge D1, a capacitor C1, and a capacitor C3. The second pin of the rectifier bridge D1 is connected to the first end of the corresponding power supply interface, the fourth pin of the rectifier bridge D1 is connected to the second end of the corresponding power supply interface, the third pin of the rectifier bridge D1 is grounded, and the first pin of the rectifier bridge D1 is connected to the input end of the constant current output module and the input end of the power supply module, respectively, and is grounded through capacitors C1 and C3, respectively.

[0007] Preferably, the constant current output module includes an operational amplifier U2, MOSFETs Q1 and Q3, resistors R1, R2, R3, R4, R6, and R7, capacitors C9 and C18, diodes D2, D3, D5, D6, and D8, and at least one adjustment circuit. The non-inverting input of the operational amplifier U2 is connected to the anode of diode D2 and the cathode of diode D3, respectively, and is connected to the main control module through resistor R1. The inverting input of the operational amplifier U2 is connected to the first end of resistor R3, and the first end of resistor R3 is connected to the cathode of diode D2. The anode of diode D3 is connected to the output terminal of operational amplifier U2 via capacitor C9. The output terminal of operational amplifier U2 is connected to the gate of MOSFET Q1 via resistor R2. The second terminal of resistor R3 is connected to the first terminal of resistor R4. The drain of MOSFET Q1 is connected to the output terminal of the power input module. The source of MOSFET Q1 is connected to the first terminal of resistor R4. The first terminal of resistor R4 is grounded via an adjustment circuit. The second terminal of resistor R4 outputs DC and is grounded via diode D6, diode D8, and capacitor C18. The second terminal of resistor R4 is connected to the power supply via diode D5.

[0008] Preferably, the power input module further includes an adjustment chip U6, and the adjustment circuit is provided in several parts, with the control terminals of the several adjustment circuits all connected to the corresponding ports of the adjustment chip U6.

[0009] Preferably, the adjustment circuit includes a MOSFET Q3, a resistor R6, and a resistor R7. The drain of the MOSFET Q3 is connected to the first end of the resistor R4 through the resistor R7. The gate of the MOSFET Q3 is connected to the Y0 port of the adjustment chip U6 through the resistor R6. The source of the MOSFET Q3 is grounded.

[0010] Preferably, the output terminal of the constant current output module is connected to the AIN(+) port of the current feedback module, the REFIN(+) port of the current feedback module is connected to the reference point, and the SCLK port, DIN port, CS port and DOUT port of the current feedback module are all connected to the corresponding ports of the main control module.

[0011] Preferably, the power supply module includes a power supply chip U4, an inductor L1, a diode D4, a capacitor C6, and a capacitor C7. The VIN terminal of the power supply chip U4 is connected to the output terminal of the power input module and grounded through the capacitor C6. The OUT port of the power supply chip U4 is connected to the first terminal of the inductor L1 and grounded through the diode D4. The second terminal of the inductor L1 outputs power and is grounded through the capacitor C7. The second terminal of the inductor L1 is connected to the FB port of the power supply chip U4.

[0012] Preferably, the main control module further includes a power management module, which includes a voltage regulator chip U7, capacitors C16, C17, C24, C25, C26, C27, C28, and C29. The VIN port of the voltage regulator chip U7 is connected to the output terminal of the power supply module and grounded through capacitors C16 and C17 respectively. The VOUT port of the voltage regulator chip U7 is connected to the power supply terminal of the main control module, and the power supply terminal of the main control module is grounded through capacitors C24, C25, C26, C27, C28, and C29 respectively.

[0013] Preferably, the main control module further includes a current control module, which includes a conversion chip U12. The SYNC port, SCLK port, and DIN port of the conversion chip U12 are all connected to the main control module. The VOUT port of the main control module is connected to the control terminal of the constant current output module.

[0014] Preferably, the communication module includes a communication chip M1, the TX port, DR port and RX port of the communication chip M1 are all connected to the main control module, and the 485A port and 485B port of the communication chip M1 are all connected to the corresponding communication bus.

[0015] The beneficial technical effects of this utility model include:

[0016] This invention can achieve a series of tasks such as power supply filtering, constant current output, real-time monitoring of output current, and network communication of constant current source. It has a high degree of automation and intelligence, high control precision, and is convenient for digital control, making the constant current source highly programmable and flexible, easy to use, and versatile.

[0017] Other features and advantages of this utility model will be disclosed in detail in the following specific embodiments and accompanying drawings. Attached Figure Description

[0018] The present invention will be further described below with reference to the accompanying drawings:

[0019] Figure 1 This is a circuit structure diagram of a constant current source with high control precision;

[0020] Figure 2 This is the circuit structure diagram of the power input module;

[0021] Figure 3 Circuit structure of constant current output module Figure 1 ;

[0022] Figure 4 Circuit structure of constant current output module Figure 2 ;

[0023] Figure 5 This is the circuit structure diagram of the current control module;

[0024] Figure 6 This is the circuit diagram of the power supply module;

[0025] Figure 7 The circuit structure diagram of the main control module;

[0026] Figure 8 The circuit structure diagram of the main control module and the power supply module;

[0027] Figure 9 This is the circuit structure diagram of the current feedback module;

[0028] Figure 10 This is the circuit structure diagram of the communication module. Detailed Implementation

[0029] The technical solutions of the present utility model will be explained and described below with reference to the accompanying drawings. However, the following embodiments are only preferred embodiments of the present utility model and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments in the implementation methods without creative effort are all within the protection scope of the present utility model.

[0030] In the following description, terms such as “inner,” “outer,” “upper,” “lower,” “left,” and “right” are used only to facilitate the description of the embodiments and simplify the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0031] Please see Figures 1 to 10 This embodiment discloses a constant current source with high control precision, including a power input module 1 for power input and preliminary filtering, a constant current output module 2 for achieving constant current output, a main control module 3 for overall control, a current feedback module 4 for monitoring current, a communication module 5 for communication, and a power supply module 6 for power supply. The following is a detailed description with reference to the accompanying drawings.

[0032] In this embodiment, the input terminal of the power input module 1 is connected to the corresponding power supply interface, the output terminal of the power input module 1 is connected to the input terminal of the constant current output module 2 and the input terminal of the power supply module 6, the monitoring terminal of the current feedback module 4 is connected to the output terminal of the constant current output module 2, the power supply module 6 provides power to the constant current output module 2, the main control module 3, the current feedback module 4 and the communication module 5, the control terminal of the constant current output module 2 and the signal output terminal of the current feedback module 4 are both connected to the main control module 3, and the main control module 3 is connected to the corresponding communication bus through the communication module 5.

[0033] When this embodiment is working, it can achieve a series of tasks such as power supply filtering, constant current output, real-time monitoring of output current, and network communication of constant current source. It has a high degree of automation and intelligence, high control precision, and is convenient for digital control, which makes the constant current source highly programmable and flexible, easy to use, and versatile.

[0034] Preferably, the power input module 1 includes a rectifier bridge D1, capacitor C1, and capacitor C3. The second pin of the rectifier bridge D1 is connected to the first terminal of the corresponding power supply interface, the fourth pin of the rectifier bridge D1 is connected to the second terminal of the corresponding power supply interface, and the third pin of the rectifier bridge D1 is grounded. The first pin of the rectifier bridge D1 is connected to the input terminal of the constant current output module 2 and the input terminal of the power supply module 6, respectively, and is grounded through capacitor C1 and capacitor C3, respectively. During operation, the power supply can be initially filtered through capacitor C1 and capacitor C3 to ensure that the power supply input to the subsequent circuit is more stable.

[0035] In this embodiment, the constant current output module 2 includes an operational amplifier U2, MOSFETs Q1 and Q3, resistors R1, R2, R3, R4, R6, and R7, capacitors C9 and C18, diodes D2, D3, D5, D6, and D8, and at least one adjustment circuit. The non-inverting input terminal of the operational amplifier U2 is connected to the anode of diode D2 and the cathode of diode D3, respectively, and is connected to the main control module 3 through resistor R1. The inverting input terminal of the operational amplifier U2 is connected to the first end of resistor R3. The first end of resistor R3 is connected to the cathode of diode D2 and the anode of diode D3, respectively, and is connected to the output terminal of the operational amplifier U2 through capacitor C9. The output of amplifier U2 is connected to the gate of MOSFET Q1 through resistor R2. The second end of resistor R3 is connected to the first end of resistor R4. The drain of MOSFET Q1 is connected to the output of power input module 1. The source of MOSFET Q1 is connected to the first end of resistor R4. The first end of resistor R4 is grounded through the adjustment circuit. The second end of resistor R4 is a DC output and is grounded through diodes D6, D8, and C18. The second end of resistor R4 is connected to the power supply through diode D5. During operation, the conduction level of MOSFET Q1 is controlled by operational amplifier U2, which can achieve constant output of different currents. The current can be precisely controlled by adjusting the circuit and the load, and overvoltage will not occur, resulting in a high safety factor.

[0036] As a further improvement to this embodiment, a fuse can also be provided so that the drain of MOSFET Q1 is connected to the output terminal of power input module 1 through the fuse, which can play a protective role in case of overload. At the same time, MOSFET Q1 can be made replaceable, and different specifications of MOSFET Q1 can be quickly replaced by adding interface P7, which can be used in different operating environments and has good versatility.

[0037] In a specific implementation, the power input module 1 also includes an adjustment chip U6. Several adjustment circuits are provided, and the control terminals of the several adjustment circuits are all connected to the corresponding ports of the adjustment chip U6. In this embodiment, the adjustment circuit includes a MOSFET Q3, a resistor R6, and a resistor R7. The drain of the MOSFET Q3 is connected to the first end of the resistor R4 through the resistor R7. The gate of the MOSFET Q3 is connected to the Y0 port of the adjustment chip U6 through the resistor R6. The source of the MOSFET Q3 is grounded. It can achieve the function of current limiting while completing the adjustment work. It can also prevent the voltage from rising indefinitely when the working load is disconnected, and has a high safety factor.

[0038] Preferably, the output terminal of the constant current output module 2 is connected to the AIN+ port of the current feedback module 4, the REFIN+ port of the current feedback module 4 is connected to the reference point, and the SCLK port, DIN port, CS port and DOUT port of the current feedback module 4 are all connected to the corresponding ports of the main control module 3. During operation, closed-loop control of the current can be realized, which facilitates precise control of the constant current output.

[0039] In this embodiment, the power supply module 6 includes a power supply chip U4, an inductor L1, a diode D4, a capacitor C6, and a capacitor C7. The VIN terminal of the power supply chip U4 is connected to the output terminal of the power input module 1 and grounded through the capacitor C6. The OUT port of the power supply chip U4 is connected to the first terminal of the inductor L1 and grounded through the diode D4. The second terminal of the inductor L1 outputs power and is grounded through the capacitor C7. The second terminal of the inductor L1 is connected to the FB port of the power supply chip U4. During operation, the inductor L1 and capacitor C7 further filter and store energy to ensure that the output power is more stable and pure, providing reliable power support for subsequent constant current output.

[0040] Preferably, the main control module 3 also includes a power management module, which includes a voltage regulator chip U7, capacitors C16, C17, C24, C25, C26, C27, C28, and C29. The VIN port of the voltage regulator chip U7 is connected to the output terminal of the power supply module 6 and grounded through capacitors C16 and C17 respectively. The VOUT port of the voltage regulator chip U7 is connected to the power supply terminal of the main control module 3. The power supply terminal of the main control module 3 is connected through capacitors C24, C25, C26, and C29 respectively. C27, C28, and C29 are grounded. During operation, they can further filter the power supply, removing ripple and interference, and ensuring that the power input to the main control module 3 is more stable and pure. Preferably, the main control module 3 also includes a current control module, which includes a conversion chip U12. The SYNC port, SCLK port, and DIN port of the conversion chip U12 are all connected to the main control module 3. The VOUT port of the main control module 3 is connected to the control terminal of the constant current output module 2, which can realize the conversion of the control signal of the main control module 3.

[0041] In this embodiment, the communication module 5 includes a communication chip M1. The TX port, DR port and RX port of the communication chip M1 are all connected to the main control module 3. The 485A port and 485B port of the communication chip M1 are all connected to the corresponding communication bus. Of course, any other existing communication circuit can also be used, such as Bluetooth circuit, WIFI circuit, etc.

[0042] The beneficial technical effects of this embodiment include: the present invention can realize a series of tasks such as power supply filtering, constant current output, real-time monitoring of output current, and network communication of constant current source. It has a high degree of automation and intelligence, high control precision, and is convenient for digital control, making the constant current source highly programmable and flexible, easy to use, and versatile.

[0043] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Those skilled in the art should understand that this utility model includes, but is not limited to, the content described in the accompanying drawings and the specific embodiments above. Any modifications that do not depart from the functional and structural principles of this utility model will be included within the scope of the claims.

Claims

1. A constant current source with high control precision, characterized in that: The system includes a power input module (1) for power input and preliminary filtering, a constant current output module (2) for achieving constant current output, a main control module (3) for overall control, a current feedback module (4) for monitoring current, a communication module (5) for communication, and a power supply module (6) for power supply. The input terminal of the power input module (1) is connected to the corresponding power supply interface. The output terminal of the power input module (1) is connected to the input terminal of the constant current output module (2) and the input terminal of the power supply module (6). The monitoring terminal of the current feedback module (4) is connected to the output terminal of the constant current output module (2). The power supply module (6) supplies power to the constant current output module (2), the main control module (3), the current feedback module (4), and the communication module (5). The control terminal of the constant current output module (2) and the signal output terminal of the current feedback module (4) are both connected to the main control module (3). The main control module (3) is connected to the corresponding communication bus through the communication module (5).

2. The constant current source with high control precision according to claim 1, characterized in that: The power input module (1) includes a rectifier bridge D1, a capacitor C1 and a capacitor C3. The second pin of the rectifier bridge D1 is connected to the first end of the corresponding power supply interface. The fourth pin of the rectifier bridge D1 is connected to the second end of the corresponding power supply interface. The third pin of the rectifier bridge D1 is grounded. The first pin of the rectifier bridge D1 is connected to the input end of the constant current output module (2) and the input end of the power supply module (6) respectively, and is grounded through capacitor C1 and capacitor C3 respectively.

3. A constant current source with high control precision according to claim 1, characterized in that: The constant current output module (2) includes an operational amplifier U2, MOSFETs Q1 and Q3, resistors R1, R2, R3, R4, R6, and R7, capacitors C9 and C18, diodes D2, D3, D5, D6, and D8, and at least one adjustment circuit. The non-inverting input terminal of the operational amplifier U2 is connected to the anode of diode D2 and the cathode of diode D3, respectively, and is connected to the main control module (3) through resistor R1. The inverting input terminal of the operational amplifier U2 is connected to the first end of resistor R3, and the first end of resistor R3 is connected to the cathode of diode D2. The anode of diode D3 is connected to the output terminal of operational amplifier U2 via capacitor C9. The output terminal of operational amplifier U2 is connected to the gate of MOS transistor Q1 via resistor R2. The second end of resistor R3 is connected to the first end of resistor R4. The drain of MOS transistor Q1 is connected to the output terminal of power input module (1). The source of MOS transistor Q1 is connected to the first end of resistor R4. The first end of resistor R4 is grounded via adjustment circuit. The second end of resistor R4 is DC output and grounded via diode D6, diode D8 and capacitor C18 respectively. The second end of resistor R4 is connected to power supply via diode D5.

4. A constant current source with high control precision according to claim 3, characterized in that: The power input module (1) also includes an adjustment chip U6. The adjustment circuit is provided in several parts, and the control terminals of the several adjustment circuits are all connected to the corresponding ports of the adjustment chip U6.

5. A constant current source with high control precision according to claim 4, characterized in that: The adjustment circuit includes a MOSFET Q3, a resistor R6, and a resistor R7. The drain of the MOSFET Q3 is connected to the first end of the resistor R4 through the resistor R7. The gate of the MOSFET Q3 is connected to the Y0 port of the adjustment chip U6 through the resistor R6. The source of the MOSFET Q3 is grounded.

6. A constant current source with high control precision according to claim 1, characterized in that: The output terminal of the constant current output module (2) is connected to the AIN(+) port of the current feedback module (4), the REFIN(+) port of the current feedback module (4) is connected to the reference point, and the SCLK port, DIN port, CS port and DOUT port of the current feedback module (4) are all connected to the corresponding ports of the main control module (3).

7. A constant current source with high control precision according to claim 1, characterized in that: The power supply module (6) includes a power supply chip U4, an inductor L1, a diode D4, a capacitor C6, and a capacitor C7. The VIN terminal of the power supply chip U4 is connected to the output terminal of the power input module (1) and grounded through the capacitor C6. The OUT port of the power supply chip U4 is connected to the first terminal of the inductor L1 and grounded through the diode D4. The second terminal of the inductor L1 outputs power and is grounded through the capacitor C7. The second terminal of the inductor L1 is connected to the FB port of the power supply chip U4.

8. A constant current source with high control precision according to claim 1, characterized in that: The main control module (3) also includes a power management module, which includes a voltage regulator chip U7, capacitors C16, C17, C24, C25, C26, C27, C28 and C29. The VIN port of the voltage regulator chip U7 is connected to the output terminal of the power supply module (6) and grounded through capacitors C16 and C17 respectively. The VOUT port of the voltage regulator chip U7 is connected to the power supply terminal of the main control module (3). The power supply terminal of the main control module (3) is grounded through capacitors C24, C25, C26, C27, C28 and C29 respectively.

9. A constant current source with high control precision according to claim 1, characterized in that: The main control module (3) also includes a current control module, which includes a conversion chip U12. The SYNC port, SCLK port and DIN port of the conversion chip U12 are all connected to the main control module (3). The VOUT port of the main control module (3) is connected to the control terminal of the constant current output module (2).

10. A constant current source with high control precision according to claim 1, characterized in that: The communication module (5) includes a communication chip M1. The TX port, DR port and RX port of the communication chip M1 are all connected to the main control module (3). The 485A port and 485B port of the communication chip M1 are all connected to the corresponding communication bus.

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