阅读说明：本技术 一种恒流源电路及其驱动方法、电流控制装置 (Constant current source circuit, driving method thereof and current control device ) 是由 冯天一 耿伟彪 任璟睿 李文禹 张玉佳 于 2021-03-10 设计创作，主要内容包括：本发明提供一种恒流源电路及其驱动方法、电流控制装置,涉及恒流源设计技术领域,能够提升输出的电流精度。所述恒流源电路中,电位调节子电路分别与基础信号输入端,第一放大子电路的第一输入端和第一电平信号输入端耦接；第一放大子电路的第二输入端与第二放大子电路的输出端耦接,第一放大子电路的输出端与第二放大子电路的输入端耦接；第二放大子电路还与第二电平信号输入端耦接。(The invention provides a constant current source circuit, a driving method thereof and a current control device, relates to the technical field of constant current source design, and can improve the accuracy of output current. In the constant current source circuit, a potential adjusting sub-circuit is respectively coupled with a basic signal input end, a first input end of a first amplifying sub-circuit and a first level signal input end; the second input end of the first amplification sub-circuit is coupled with the output end of the second amplification sub-circuit, and the output end of the first amplification sub-circuit is coupled with the input end of the second amplification sub-circuit; the second amplifying sub-circuit is also coupled with the second level signal input end.)

1. A constant current source circuit, comprising: a potential adjusting sub-circuit, a first amplifying sub-circuit and a second amplifying sub-circuit; wherein the content of the first and second substances,

the potential adjusting sub-circuit is respectively coupled with the basic signal input end, the first input end of the first amplifying sub-circuit and the first level signal input end; for: adjusting a first transition signal transmitted to the first input terminal based on a base signal input by the base signal input terminal;

a second input terminal of the first amplification sub-circuit is coupled to an output terminal of the second amplification sub-circuit, and an output terminal of the first amplification sub-circuit is coupled to an input terminal of the second amplification sub-circuit; for: obtaining a second transition signal according to the first transition signal and a target signal received by the second input end, and transmitting the second transition signal to the input end of the second amplification sub-circuit;

the second amplifying sub-circuit is also coupled with the second level signal input end; for: and amplifying the second transition signal output by the output end of the first amplification sub-circuit, and outputting a target signal obtained after amplification.

2. The constant current source circuit according to claim 1, further comprising:

the control sub-circuit is respectively coupled with the output ends of the potential adjusting sub-circuit and the first amplifying sub-circuit; for: and controlling the potential adjusting sub-circuit to transmit the first transition signal to the first input end according to the second transition signal.

3. The constant current source circuit according to claim 2, wherein the potential adjusting sub-circuit comprises: the device comprises a first fixed resistor, a second fixed resistor and an adjustable potentiometer;

a first terminal of the first fixed resistor is coupled to the base signal input terminal, and a second terminal of the first fixed resistor is coupled to a first terminal of the adjustable potentiometer;

a first end of the second fixed resistor is coupled to the first level signal input end, and a second end of the second fixed resistor is coupled to a second end of the adjustable potentiometer;

the control end of the adjustable potentiometer is coupled with the first input ends of the control sub-circuit and the first amplification sub-circuit respectively.

4. The constant current source circuit according to claim 1, wherein the first amplification sub-circuit comprises:

and the non-inverting input end of the operational amplifier is used as the first input end, the inverting input end of the operational amplifier is used as the second input end, the first power end of the operational amplifier is coupled with the second level signal input end, and the second power end of the operational amplifier is coupled with the third level signal input end.

5. The constant current source circuit according to claim 1, wherein the second amplification sub-circuit comprises:

the base of the Darlington tube is used as the input end of the second amplification sub-circuit, the collector of the Darlington tube is coupled with the second level signal input end, and the emitting electrode of the Darlington tube is used as the output end of the second amplification sub-circuit.

6. The constant current source circuit according to claim 1, further comprising:

a filter sub-circuit coupled to an input of the second amplification sub-circuit and the first level signal input, respectively; and/or the presence of a gas in the gas,

and the overcurrent protection sub-circuit is respectively coupled with the output end of the first amplification sub-circuit and the input end of the second amplification sub-circuit.

7. The constant current source circuit according to claim 1, further comprising:

the first voltage stabilizing circuit is coupled with the output end of the second amplifying sub-circuit and the first level signal input end respectively; and/or the presence of a gas in the gas,

and the second voltage stabilizing circuit is respectively coupled with the first input end of the first amplifying sub-circuit and the first level signal input end.

8. A current control device comprising the constant current source circuit according to any one of claims 1 to 7, the current control device further comprising:

the control system is coupled with the constant current source circuit and used for outputting a basic signal to the constant current source circuit and receiving a target signal fed back by the constant current source circuit;

an input module coupled to the control system for inputting an input signal matching the target signal;

a display module coupled to the control system for displaying the input signal;

a power module coupled to the constant current source circuit for providing a first level signal and a second level signal.

9. The current control device of claim 8, wherein the control system comprises:

the single chip microcomputer control circuit is respectively coupled with the input module and the display module;

the input end of the digital-to-analog converter is coupled with the output end of the singlechip control circuit, and the output end of the digital-to-analog converter is coupled with the constant current source circuit; the digital-to-analog converter is used for outputting a basic signal to the constant current source circuit;

the input end of the analog-to-digital converter is coupled with the constant current source circuit, and the output end of the analog-to-digital converter is connected with the singlechip control circuit; the analog-to-digital converter is used for receiving a target signal fed back by the constant current source circuit.

10. A constant current source circuit driving method for driving the constant current source circuit according to any one of claims 1 to 7, wherein potential adjusting sub-circuits are respectively coupled to a base signal input terminal, a first input terminal of the first amplifying sub-circuit and a first level signal input terminal; a second input terminal of the first amplification sub-circuit is coupled to an output terminal of the second amplification sub-circuit, and an output terminal of the first amplification sub-circuit is coupled to an input terminal of the second amplification sub-circuit; the second amplifying sub-circuit is also coupled with the second level signal input end;

the driving method includes:

the potential adjusting sub-circuit adjusts a first transition signal transmitted to the first input end based on a basic signal input by the basic signal input end;

the first amplification sub-circuit obtains a second transition signal according to the first transition signal and the target signal received by the second input end, and transmits the second transition signal to the input end of the second amplification sub-circuit;

and the second amplification sub-circuit amplifies the second transition signal output by the output end of the first amplification sub-circuit and outputs a target signal obtained after amplification.

Technical Field

The invention relates to the technical field of constant current source design, in particular to a constant current source circuit, a driving method thereof and a current control device.

Background

The constant current source is a wide-frequency-spectrum current-stabilizing power supply and is a current source capable of keeping the output current constant. An ideal constant current source has the following characteristics: does not change due to load changes; does not change due to the change of the environmental temperature; the internal resistance is infinite so that the current can flow out to the outside entirely.

Although the existing constant current source has the advantages of high response speed, capability of working stably for a long time, suitability for loads with various properties (such as resistance, inductance and capacitance) and the like, the accuracy of the output current is limited, and the requirement cannot be met in many cases.

Disclosure of Invention

The invention aims to provide a constant current source circuit, a driving method thereof and a current control device, which can improve the accuracy of output current.

In order to achieve the above purpose, the invention provides the following technical scheme:

a first aspect of the present invention provides a constant current source circuit comprising: a potential adjusting sub-circuit, a first amplifying sub-circuit and a second amplifying sub-circuit; wherein the content of the first and second substances,

the potential adjusting sub-circuit is respectively coupled with the basic signal input end, the first input end of the first amplifying sub-circuit and the first level signal input end; for: adjusting a first transition signal transmitted to the first input terminal based on a base signal input by the base signal input terminal;

a second input terminal of the first amplification sub-circuit is coupled to an output terminal of the second amplification sub-circuit, and an output terminal of the first amplification sub-circuit is coupled to an input terminal of the second amplification sub-circuit; for: obtaining a second transition signal according to the first transition signal and a target signal received by the second input end, and transmitting the second transition signal to the input end of the second amplification sub-circuit;

the second amplifying sub-circuit is also coupled with the second level signal input end; for: and amplifying the second transition signal output by the output end of the first amplification sub-circuit, and outputting a target signal obtained after amplification.

Optionally, the constant current source circuit further includes:

the control sub-circuit is respectively coupled with the output ends of the potential adjusting sub-circuit and the first amplifying sub-circuit; for: and controlling the potential adjusting sub-circuit to transmit the first transition signal to the first input end according to the second transition signal.

Optionally, the potential adjustment sub-circuit includes: the device comprises a first fixed resistor, a second fixed resistor and an adjustable potentiometer;

a first terminal of the first fixed resistor is coupled to the base signal input terminal, and a second terminal of the first fixed resistor is coupled to a first terminal of the adjustable potentiometer;

a first end of the second fixed resistor is coupled to the first level signal input end, and a second end of the second fixed resistor is coupled to a second end of the adjustable potentiometer;

the control end of the adjustable potentiometer is coupled with the first input ends of the control sub-circuit and the first amplification sub-circuit respectively.

Optionally, the first amplifying sub-circuit includes:

and the non-inverting input end of the operational amplifier is used as the first input end, the inverting input end of the operational amplifier is used as the second input end, the first power end of the operational amplifier is coupled with the second level signal input end, and the second power end of the operational amplifier is coupled with the third level signal input end.

Optionally, the second amplifying sub-circuit includes:

the base of the Darlington tube is used as the input end of the second amplification sub-circuit, the collector of the Darlington tube is coupled with the second level signal input end, and the emitting electrode of the Darlington tube is used as the output end of the second amplification sub-circuit.

Optionally, the constant current source circuit further includes:

a filter sub-circuit coupled to an input of the second amplification sub-circuit and the first level signal input, respectively; and/or the presence of a gas in the gas,

and the overcurrent protection sub-circuit is respectively coupled with the output end of the first amplification sub-circuit and the input end of the second amplification sub-circuit.

Optionally, the constant current source circuit further includes:

the first voltage stabilizing circuit is coupled with the output end of the second amplifying sub-circuit and the first level signal input end respectively; and/or the presence of a gas in the gas,

and the second voltage stabilizing circuit is respectively coupled with the first input end of the first amplifying sub-circuit and the first level signal input end.

In view of the specific configuration of the constant current source circuit, a second aspect of the present invention provides a current control device including the constant current source circuit, the current control device further including:

the control system is coupled with the constant current source circuit and used for outputting a basic signal to the constant current source circuit and receiving a target signal fed back by the constant current source circuit;

an input module coupled to the control system for inputting an input signal matching the target signal;

a display module coupled to the control system for displaying the input signal;

a power module coupled to the constant current source circuit for providing a first level signal and a second level signal.

Optionally, the control system includes:

the single chip microcomputer control circuit is respectively coupled with the input module and the display module;

the input end of the digital-to-analog converter is coupled with the output end of the singlechip control circuit, and the output end of the digital-to-analog converter is coupled with the constant current source circuit; the digital-to-analog converter is used for outputting a basic signal to the constant current source circuit;

the input end of the analog-to-digital converter is coupled with the constant current source circuit, and the output end of the analog-to-digital converter is connected with the singlechip control circuit; the analog-to-digital converter is used for receiving a target signal fed back by the constant current source circuit.

Based on the specific structure of the constant current source circuit, a third aspect of the present invention provides a method for driving a constant current source circuit, wherein the constant current source circuit includes a potential adjusting sub-circuit coupled to a base signal input terminal, a first input terminal of a first amplifying sub-circuit coupled to a first level signal input terminal, and a second level signal input terminal; a second input terminal of the first amplification sub-circuit is coupled to an output terminal of the second amplification sub-circuit, and an output terminal of the first amplification sub-circuit is coupled to an input terminal of the second amplification sub-circuit; the second amplifying sub-circuit is also coupled with the second level signal input end;

the driving method includes:

the potential adjusting sub-circuit adjusts a first transition signal transmitted to the first input end based on a basic signal input by the basic signal input end;

the first amplification sub-circuit obtains a second transition signal according to the first transition signal and the target signal received by the second input end, and transmits the second transition signal to the input end of the second amplification sub-circuit;

and the second amplification sub-circuit amplifies the second transition signal output by the output end of the first amplification sub-circuit and outputs a target signal obtained after amplification.

In the technical scheme provided by the invention, the constant current source circuit comprises a potential adjusting sub-circuit, a first amplifying sub-circuit and a second amplifying sub-circuit, wherein the potential adjusting sub-circuit can accurately convert a received basic signal into a corresponding first transition signal through self-accurate adjustment and then output the first transition signal to the first amplifying sub-circuit, and the first transition signal is amplified by the first amplifying sub-circuit and the second amplifying sub-circuit to obtain an accurate target signal for a load to use. Therefore, the constant current source circuit provided by the invention can realize accurate target signal output.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic structural diagram of a constant current source circuit according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a current control device according to an embodiment of the present invention.

Detailed Description

In order to further explain the constant current source circuit, the driving method thereof and the current control device provided by the embodiment of the invention, the following is described in detail with reference to the accompanying drawings.

Referring to fig. 1, an embodiment of the present invention provides a constant current source circuit, including: a potential adjusting sub-circuit 10, a first amplifying sub-circuit 20 and a second amplifying sub-circuit 30; wherein the content of the first and second substances,

the potential adjusting sub-circuit 10 is coupled to the basic signal input terminal, the first input terminal of the first amplifying sub-circuit 20 and the first level signal input terminal, respectively; for: adjusting a first transition signal transmitted to the first input terminal based on a base signal input by the base signal input terminal;

a second input of the first amplification sub-circuit 20 is coupled to an output of the second amplification sub-circuit 30, and an output of the first amplification sub-circuit 20 is coupled to an input of the second amplification sub-circuit 30; for: obtaining a second transition signal according to the first transition signal and the target signal received by the second input terminal, and transmitting the second transition signal to the input terminal of the second amplifying sub-circuit 30;

the second amplification sub-circuit 30 is further coupled to a second level signal input terminal; for: and amplifying the second transition signal output by the output end of the first amplifying sub-circuit 20, and outputting a target signal obtained after amplification.

Illustratively, the base signal input inputs a base signal, which comprises an analog signal. Illustratively, the analog signal includes a voltage signal or a current signal.

Illustratively, the first level signal input end inputs a first level signal, and the first level signal comprises a ground signal or a negative power supply signal.

Illustratively, the second level signal input terminal inputs a second level signal, and the second level signal comprises a positive power supply signal.

Illustratively, the level adjustment sub-circuit 10 is capable of receiving the base signal from the base signal input terminal, deriving the first transition signal from the base signal, and outputting the first transition signal to the first input terminal of the first amplification sub-circuit 20.

Illustratively, the first amplification sub-circuit 20 is further coupled to a power supply module for supplying power to the first amplification sub-circuit 20. Illustratively, the power module is capable of providing a positive power signal and a negative power signal. Illustratively, the power module is coupled to the first level signal input terminal to provide a first level signal to the first level signal input terminal. Illustratively, the power module is coupled to the second level signal input terminal to provide a second level signal to the second level signal input terminal.

Illustratively, the first amplifying sub-circuit 20 is capable of amplifying the first transition signal according to the first transition signal and the target signal received by the second input terminal to obtain the second transition signal, and outputting the second transition signal to the input terminal of the second amplifying sub-circuit 30.

For example, the second amplifying sub-circuit 30 can amplify the second transition signal output by the output terminal of the first amplifying sub-circuit 20, and output the amplified target signal to the load.

As can be seen from the specific structure of the constant current source circuit, the constant current source circuit provided in the embodiment of the present invention includes a potential adjusting sub-circuit 10, a first amplifying sub-circuit 20 and a second amplifying sub-circuit 30, where the potential adjusting sub-circuit 10 can accurately convert a received basic signal into a corresponding first transition signal through its own accurate adjustment, and output the first transition signal to the first amplifying sub-circuit 20, and the first transition signal is amplified by the first amplifying sub-circuit 20 and the second amplifying sub-circuit 30 to obtain an accurate target signal for load use. Therefore, the constant current source circuit provided by the embodiment of the invention can realize accurate target signal output.

In some embodiments, the constant current source circuit further comprises a control sub-circuit coupled to the output terminals of the potential adjusting sub-circuit 10 and the first amplifying sub-circuit 20, respectively; for: and controlling the potential adjusting sub-circuit 10 to transmit the first transition signal to the first input end according to the second transition signal.

When the constant current source circuit is applied to a current control device, the control sub-circuit is part of a control system of the current control device.

Illustratively, one input of the control sub-circuit is coupled to the output of the first amplifying sub-circuit 20, and receives the first transition signal output by the first amplifying sub-circuit 20, and one output of the control sub-circuit is coupled to the electric potential adjusting sub-circuit 10, and the control sub-circuit can perform accurate adjustment on the electric potential adjusting sub-circuit 10 based on the first transition signal, so as to adjust the first transition signal that is transmitted by the electric potential adjusting sub-circuit 10 to the first input again.

In the constant current source circuit provided in the foregoing embodiment, by providing the control sub-circuit, the potential adjusting sub-circuit 10 can be adjusted based on a first transition signal generated in the previous time, so as to adjust the first transition signal that is transmitted to the first input terminal again by the potential adjusting sub-circuit 10; therefore, the constant current source circuit provided by the above embodiment can realize real-time adjustment of the first transition signal, and further realize real-time adjustment of the target signal, so that the constant current source circuit can realize accurate current signal output.

As shown in fig. 1, in some embodiments, the potential adjustment sub-circuit 10 includes: a first fixed resistor R1, a second fixed resistor R2 and an adjustable potentiometer R3;

a first terminal of the first fixed resistor R1 is coupled to the base signal input terminal, and a second terminal of the first fixed resistor R1 is coupled to a first terminal of the adjustable potentiometer R3;

a first terminal of the second fixed resistor R2 is coupled to the first level signal input terminal V1, and a second terminal of the second fixed resistor R2 is coupled to a second terminal of the adjustable potentiometer R3;

the control terminal of the adjustable potentiometer R3 is coupled to the control sub-circuit and the first input terminal of the first amplifying sub-circuit 20, respectively.

Illustratively, the first fixed resistor R1 includes a resistance of 3.6 kilo-ohms, the second fixed resistor R2 includes a resistance of 1 kilo-ohms, and the adjustable potentiometer R3 includes a resistance of 1 kilo-ohms.

For example, as shown in fig. 1, the lower portion of the adjustable potentiometer R3 and the second fixed resistor R2 divide the voltage to determine the voltage of the first transition signal output to the first input terminal. By adjusting the resistance of the adjustable potentiometer R3, the potential of the first transition signal output to the first input terminal can be adjusted, thereby changing the potential of the target signal.

In the constant current source circuit provided in the above embodiment, the adjustable potentiometer R3 is adjusted to accurately convert the received basic signal into a corresponding first transition signal, and after the first transition signal is amplified by the first amplification sub-circuit 20 and the second amplification sub-circuit 30, an accurate target signal is obtained for the load to use. Therefore, in the constant current source circuit provided in the above-described embodiment, by configuring the potential adjustment sub-circuit 10 to include the first fixed resistor R1, the second fixed resistor R2, and the adjustable potentiometer R3, the output accuracy of the target signal is effectively improved.

As shown in fig. 1, in some embodiments, the first amplification sub-circuit 20 includes:

and the non-inverting input end of the operational amplifier is used as the first input end, the inverting input end of the operational amplifier is used as the second input end, the first power end of the operational amplifier is coupled with the second level signal input end, and the second power end of the operational amplifier is coupled with the third level signal input end.

Illustratively, the operational amplifier comprises OP07, and OP07 is a low noise, non-chopper-stabilized bipolar (dual power supply) operational amplifier integrated circuit. Since OP07 has a very low input offset voltage (maximum 25 μ V for OP 07A), OP07 does not require additional zeroing measures in many applications. And OP07 has the following properties: ultra-low offset: 150 μ V max. Low input bias current: 1.8 nA. Low offset voltage drift: 0.5. mu.V/. degree.C. Ultra-stable time: 2 μ V/month. Maximum high supply voltage range: 3V to 22V.

Illustratively, the second level signal input terminal inputs a positive power supply signal, and the third level signal input terminal inputs a negative power supply signal. Illustratively, the potential of the positive power supply signal comprises +15V and the potential of the negative power supply signal comprises-15V.

For example, the operational amplifier determines an amplification gain according to the inputs of the first input terminal and the second input terminal, and amplifies the first transition signal according to the first transition signal input by the first input terminal and the gain to obtain a second transition signal.

As shown in fig. 1, in some embodiments, the second amplification sub-circuit 30 includes:

a darlington transistor Q1, a base of the darlington transistor Q1 being an input terminal of the second amplification sub-circuit 30, a collector of the darlington transistor Q1 being coupled to the second level signal input terminal, and an emitter of the darlington transistor Q1 being an output terminal of the second amplification sub-circuit 30.

It should be noted that the darlington transistor is formed by connecting two triodes together, and the polarity of the darlington transistor is only identified as the preceding triode. The specific connection method is as follows, taking two triodes with the same polarity as an example, the collector of the front triode is connected with the collector of the rear triode, the emitter of the front triode is connected with the base of the rear triode, the power of the front triode is generally smaller than that of the rear triode, the base of the front triode is the base of a Darlington tube, the emitter of the rear triode is the emitter of the Darlington tube, the usage is the same as that of the triodes, and the amplification factor is the product of the amplification factors of the two trio.

The current of the collector (C pin) of the Darlington tube can be increased by changing the potential of the base (B pin) of the Darlington tube. The current of the emitter (E pin) of the Darlington tube is increased by increasing the current of the collector (C pin) of the Darlington tube.

Illustratively, a power resistor is connected between the E pin of the Darlington tube and the ground, the E pin of the Darlington tube is connected with the inverting input end of the OP07, the potential of the power resistor is sent to the inverting input end of the OP07, and the potential of the B pin of the base of the Darlington tube is clamped by comparing the inverting input end and the non-inverting input end of the OP 07.

The second amplification sub-circuit 30 is configured to include a darlington tube, and output of a large current can be achieved by using a current amplification characteristic of the darlington tube.

As shown in fig. 1, in some embodiments, the constant current source circuit further comprises:

a filter sub-circuit 40, said filter sub-circuit 40 being coupled to an input of said second amplification sub-circuit 30 and to said first level signal input V1, respectively.

Illustratively, the filtering sub-circuit 40 includes a first capacitor C1, a first terminal of the first capacitor C1 is coupled to the input terminal of the second amplifying sub-circuit 30, and a second terminal of the first capacitor C1 is coupled to the first level signal input terminal. Illustratively, the capacitance value of the first capacitor C1 includes 1 μ f.

The first transition signal output by the first amplification sub-circuit 20 is applied to the B pin of the darlington tube, and after entering the darlington tube, the first transition signal generates a self-excitation signal, which can be filtered out by the filtering sub-circuit 40.

As shown in fig. 1, in some embodiments, the constant current source circuit further comprises:

an over-current protection sub-circuit 50, the over-current protection sub-circuit 50 being coupled to an output of the first amplification sub-circuit 20 and an input of the second amplification sub-circuit 30, respectively.

Illustratively, the over-current protection sub-circuit 50 includes a fourth fixed resistor R4, a first terminal of the fourth fixed resistor R4 is coupled to the output terminal of the first amplification sub-circuit 20, and a second terminal of the fourth fixed resistor R4 is coupled to the input terminal of the second amplification sub-circuit 30. Illustratively, the fourth fixed resistor R4 includes a resistance of 1 kilo-ohm.

The constant current source circuit is arranged to include the overcurrent protection sub-circuit 50, so that overcurrent protection of the second amplification sub-circuit 30 is realized.

As shown in fig. 1, in some embodiments, the constant current source circuit further comprises:

and the first voltage stabilizing circuit 60 is respectively coupled with the output end of the second amplifying sub-circuit 30 and the first level signal input end V1.

Illustratively, the first regulation circuit 60 includes a fifth fixed resistor R5 and a second capacitor C2, and a first terminal of the fifth fixed resistor R5 and a first terminal of the second capacitor C2 are both coupled to the output terminal of the second amplification sub-circuit 30; a second terminal of the fifth fixed resistor R5 and a second terminal of the second capacitor C2 are both coupled to the first level signal input terminal. Illustratively, the capacitance of the second capacitor C2 includes 10 μ f, and the power consumption that the fifth fixed resistor R5 can withstand includes 1/5W.

Illustratively, the first stabilizing circuit 60 includes a second capacitor C2, and a second terminal of the second capacitor C2 is coupled to the first level signal input terminal.

The constant current source circuit further includes a first voltage stabilizing circuit 60, so that the target signal output by the second amplifying sub-circuit 30 is more stable, and the target signal fed back to the control system is more stable.

As shown in fig. 1, in some embodiments, the constant current source circuit further comprises:

a second voltage stabilizing circuit 70, wherein the second voltage stabilizing circuit 70 is respectively coupled to the first input terminal of the first amplifying sub-circuit 20 and the first level signal input terminal V1.

Illustratively, the second voltage stabilizing circuit 70 includes a third capacitor C3, a first terminal of the third capacitor C3 is coupled to the first input terminal of the first amplifying sub-circuit 20, and a second terminal of the third capacitor C3 is coupled to the first level signal input terminal.

The constant current source circuit is configured to include the second voltage stabilizing circuit 70, so that the signal input to the first input terminal of the first amplifying sub-circuit 20 is more stable.

Referring to fig. 1 and fig. 2, an embodiment of the present invention further provides a current control device, including the constant current source circuit provided in the foregoing embodiment, and the current control device further includes:

the control system is coupled with the constant current source circuit and used for outputting a basic signal to the constant current source circuit and receiving a target signal fed back by the constant current source circuit;

an input module coupled to the control system for inputting an input signal matching the target signal;

a display module coupled to the control system for displaying the input signal;

a power module coupled to the constant current source circuit for providing a first level signal and a second level signal.

Illustratively, the input module serves as a human-machine interface and comprises a 4X4 keyboard.

Illustratively, the display module comprises an LED nixie tube display, and the control interface is visual and concise and has good human-computer interaction performance.

Illustratively, the power module is capable of providing a first level signal, a second level signal and a third level signal.

Illustratively, the control system comprises an ARM chip, and the ARM chip selects the STM32F103 as a control core. And the software design of the control system adopts a PID control algorithm.

Illustratively, the constant current source circuit adopts a low-temperature drift high-common-mode rejection ratio operational amplifier OP07 and a Darlington tube TIP122 to form a constant current source topology.

The ARM chip is used for participating in control and regulation, and the PID algorithm control program is adopted, so that the accuracy of output current can be better guaranteed, the continuous regulation of current is realized, and the dynamic response speed is enhanced.

In the current control device provided by the embodiment of the invention, the microprocessor is used for replacing a manual rotary potentiometer in the traditional direct current stable power supply, and the continuous adjustment of the output current is realized by a simple and effective method. In addition, the current control device provided by the embodiment of the invention can realize keyboard input, displays the current parameters by an LCD, and has the effects of high precision and friendly man-machine interface.

In some embodiments, the control system comprises:

the single chip microcomputer control circuit is respectively coupled with the input module and the display module;

the input end of the digital-to-analog converter is coupled with the output end of the singlechip control circuit, and the output end of the digital-to-analog converter is coupled with the constant current source circuit; the digital-to-analog converter is used for outputting a basic signal to the constant current source circuit;

the input end of the analog-to-digital converter is coupled with the constant current source circuit, and the output end of the analog-to-digital converter is connected with the singlechip control circuit; the analog-to-digital converter is used for receiving a target signal fed back by the constant current source circuit.

Illustratively, the digital-to-analog converter employs a 12-bit D/A chip MAX 532.

In more detail, the input module inputs a required current to the single chip microcomputer control circuit, the single chip microcomputer control circuit outputs a corresponding small current signal to the digital-to-analog converter based on the required current, the digital-to-analog converter performs digital-to-analog conversion on the small current signal to obtain a basic signal and transmits the basic signal to the constant current source circuit, and the constant current source circuit amplifies the basic signal to obtain a target signal (namely, the required current) and provides the target signal for a load; and simultaneously, feeding the target signal back to the singlechip control circuit through the analog-to-digital converter and further feeding the target signal back to a display module, and displaying an accurate current value by the display module.

The current control device provided by the embodiment completes the real-time detection and real-time control of the single chip microcomputer control circuit on the output current (namely the target signal).

Based on the specific structure of the constant current source circuit provided in the above-described embodiment, the following specific embodiments are given.

For an existing 55-inch spliced screen, the current required by the backlight is 190mA, the total current is 10260mA in 54 areas.

The input current of the input module is 10260mA, the resistance value of the adjustable potentiometer R3 is controlled, so that the current output by the first amplification sub circuit 20 is about 1.026mA, and the voltage is about 19.8V; when the current reaches the B pin of the Darlington tube, the current of the C pin is about 102.6mA through amplification; the current is about 10260mA through the amplification E pin; the output voltage V0 is stabilized to be about 19.8V by the fifth fixed resistor R5 and the second capacitor C2.

The output voltage V0 is fed back to the inverting input end of the OP07, and if the voltage is larger, the voltage at the non-inverting input end of the OP07 is reduced by increasing the adjustable potentiometer R3; if the voltage is smaller, the voltage at the non-inverting input end of the OP07 is increased by reducing the adjustable potentiometer R3; meanwhile, the V0 is transmitted to the display module through the singlechip control circuit, so that the display module displays a numerical value of 10260 mA.

The embodiment of the present invention further provides a driving method of a constant current source circuit, which is used for driving the constant current source circuit provided in the above embodiment, in the constant current source circuit, the potential adjusting sub-circuits are respectively coupled to the basic signal input terminal, and the first input terminal of the first amplifying sub-circuit is coupled to the first level signal input terminal; a second input terminal of the first amplification sub-circuit is coupled to an output terminal of the second amplification sub-circuit, and an output terminal of the first amplification sub-circuit is coupled to an input terminal of the second amplification sub-circuit; the second amplifying sub-circuit is also coupled with the second level signal input end;

the driving method includes:

the potential adjusting sub-circuit adjusts a first transition signal transmitted to the first input end based on a basic signal input by the basic signal input end;

the first amplification sub-circuit obtains a second transition signal according to the first transition signal and the target signal received by the second input end, and transmits the second transition signal to the input end of the second amplification sub-circuit;

and the second amplification sub-circuit amplifies the second transition signal output by the output end of the first amplification sub-circuit and outputs a target signal obtained after amplification.

Illustratively, the base signal input inputs a base signal, which comprises an analog signal. Illustratively, the analog signal includes a voltage signal or a current signal.

Illustratively, the first level signal input end inputs a first level signal, and the first level signal comprises a ground signal or a negative power supply signal.

Illustratively, the second level signal input terminal inputs a second level signal, and the second level signal comprises a positive power supply signal.

For example, the potential adjustment sub-circuit may be configured to receive the base signal from the base signal input terminal, obtain the first transition signal according to the base signal, and output the first transition signal to the first input terminal of the first amplification sub-circuit.

Illustratively, the first amplifying sub-circuit is further coupled to a power supply module for supplying power to the first amplifying sub-circuit. Illustratively, the power module is capable of providing a positive power signal and a negative power signal. Illustratively, the power module is coupled to the first level signal input terminal to provide a first level signal to the first level signal input terminal. Illustratively, the power module is coupled to the second level signal input terminal to provide a second level signal to the second level signal input terminal.

For example, the first amplifying sub-circuit may amplify the first transition signal according to the first transition signal and a target signal received by the second input terminal to obtain the second transition signal, and output the second transition signal to the input terminal of the second amplifying sub-circuit.

For example, the second amplifying sub-circuit may amplify the second transition signal output by the output terminal of the first amplifying sub-circuit, and output the amplified target signal to a load.

When the constant current source circuit is driven by adopting the driving method provided by the embodiment of the invention, the received basic signal can be accurately converted into the corresponding first transition signal through accurately adjusting the potential adjusting sub-circuit and then output to the first amplifying sub-circuit, and the first transition signal is amplified by the first amplifying sub-circuit and the second amplifying sub-circuit to obtain the accurate target signal for load use. Therefore, when the constant current source circuit is driven by the driving method provided by the embodiment of the invention, accurate target signal output can be realized.

It should be noted that, in the present specification, all the embodiments are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, as for the method embodiments, since they are substantially similar to the product embodiments, they are described simply, and reference may be made to the partial description of the product embodiments for relevant points.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected," "coupled," or "connected," and the like, are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, it can be "directly on" or "under" the other element or intervening elements may be present.

In the foregoing description of embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.