Miniaturized constant current source drive circuit

Abstract

The utility model discloses a miniaturized constant current source drive circuit, which comprises an input power supply, an LDO (Low Dropout Regulator) chip, a main control chip, a constant current source control chip, a drive circuit chip, a gallium nitride high electron mobility transistor (HEMT), a feedback compensation circuit, a communication chip and an output power supply. The high thermal conductivity of the gallium nitride high electron mobility transistor (HEMT) adopted by the utility model is helpful to more effectively dissipate heat generated when a device works, and the thermal stability and reliability of a system are improved. Meanwhile, the output current is set through the communication interface, the main control chip adjusts the voltage of the compensation end in the constant current source control chip by controlling the resistance of a digital potentiometer in the feedback compensation circuit, and finally controllable adjustment of the output current is achieved. Meanwhile, the output state is monitored by the voltage acquisition loop and the current acquisition loop, so that the output is cut off in time when an abnormality occurs, and the adverse effect of the abnormality on the input power supply and the load is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of constant current source driving, and particularly relates to a miniaturized constant current source driving circuit. Background Art

[0002] After years of development, the current control circuit of high-power laser products has been gradually applied to laser weapons and anti-drone weapons. In the existing product design solutions, the control circuit and the constant current source control circuit are generally designed together, and the weak electricity and strong electricity are arranged centrally, which is not conducive to the EMC design of the overall product and also reduces the overall reliability of the product, and is even less conducive to power transmission. The centralized control circuit also means that the heat-generating components in the current control loop are concentrated, resulting in serious local heating and uneven heat generation with other components, which poses higher requirements for the heat dissipation design of the whole machine product. In addition, the problem of centralized control circuit and heat-generating components makes it difficult to plan the current transmission path, resulting in additional heat. The overall control method also reduces the overall reliability of the product. Once the control or constant current control circuit fails, the whole product will be abnormal and completely unable to work. Therefore, combined with the development needs of the industry and the miniaturized modular design of the electro-optical pump source products, it is necessary to develop a miniaturized constant current source control circuit to optimize the overall product design of laser products. Summary of the Utility Model

[0003] In order to overcome the serious local heating and poor reliability of the current control circuit in the prior art, the following technical solutions are provided:

[0004] A miniaturized constant current source driving circuit includes: an input power supply, an LDO chip, a main control chip, a constant current source control chip, a driving circuit chip, a gallium nitride high electron mobility transistor (HEMT), a feedback compensation circuit, a communication chip, and an output power supply;

[0005] The LDO chip is used to convert the input voltage of the input power supply into a stable voltage, and the converted stable voltage is used to supply power to the main control chip and the driving circuit chip;

[0006] The main functions of the main control chip include: controlling the switching operation of the output power supply, monitoring the output current, and controlling the output current;

[0007] The main functions of the constant current source control chip include: monitoring the input voltage, monitoring the input current, current limiting of the output power supply, voltage limiting of the output power supply, and output of the driving voltage;

[0008] The driving circuit chip is used for converting the driving voltage;

[0009] The gallium nitride high electron mobility transistor (HEMT) is used to reduce the heat consumption of the circuit and improve the overall efficiency;

[0010] The feedback compensation circuit contains a digital potentiometer for real-time adjustment and control of the output current.

[0011] Furthermore, the main control chip is electrically connected to the LDO chip, the constant current source control chip, the feedback compensation circuit, and the communication chip; the constant current source control chip is electrically connected to the drive circuit chip and the feedback compensation circuit; the drive circuit chip is electrically connected to the HEMT.

[0012] Furthermore, the input voltage of the input power supply is 30 - 70V, and the stable voltage converted by the LDO chip is 5V.

[0013] Furthermore, the main control chip controls the switching operation of the output power supply by controlling the level, monitors the output current by collecting the output current; completes the resistance setting of the digital potentiometer through the internal bus interaction with the digital potentiometer, and then realizes the control of the output current.

[0014] Furthermore, the main control chip realizes external communication through the interaction with the communication chip, and reports the product status using the 485 communication bus.

[0015] Furthermore, the constant current source control chip monitors the input voltage by collecting the input voltage, thereby ensuring that the voltage at the input power supply end works normally within a certain range; completes the limitation of the output maximum current and the highest voltage through the pin configuration. Once the current limiting or voltage limiting condition is triggered, the output is immediately stopped and enters the power-off state, realizing the current limitation of the output power supply and the voltage limitation of the output power supply;

[0016] Under the output current condition, the constant current source control chip monitors the input current by collecting the input current, ensuring that the current at the input end is always controlled below the set value. Once the current limiting condition is triggered, the output is immediately stopped and enters the power-off state;

[0017] Under the condition that all states meet the requirements, the constant current source control chip outputs a PWM signal as the driving voltage for driving the subsequent power switch.

[0018] Furthermore, the high and low levels of the PWM driving signal output by the constant current source control chip are 0 - 10V respectively, and the high and low levels of the HEMT driving voltage used at the back end should be 0 - 5V; the drive circuit chip is used to adjust the driving voltage from 0 - 10V to 0 - 5V on the premise that the control logic remains unchanged.

[0019] Furthermore, the feedback compensation circuit compares the filtered and amplified output current with the reference voltage after collection, and feeds back the comparison result to the constant current source control chip to realize the real-time adjustment and control of the output current.

[0020] The gallium nitride high electron mobility transistor (HEMT) adopted by the present utility model has a high thermal conductivity, which helps to more effectively dissipate the heat generated during the operation of the device, improving the thermal stability and reliability of the system. At the same time, the output current is set through the communication interface. The main control chip controls the resistance of the digital potentiometer in the feedback compensation circuit, thereby adjusting the voltage at the compensation terminal in the constant current source control chip, and finally realizing the controllable adjustment of the output current. Meanwhile, the output state is monitored by the voltage acquisition circuit and the current acquisition circuit to ensure that the output is turned off in a timely manner when an abnormality occurs, reducing the adverse effects of the abnormality on the input power supply and the load. Description of the Drawings

[0021] Figure 1 It is a circuit connection block diagram of the miniaturized constant current source drive circuit of the present utility model. Detailed Embodiment

[0022] The following combines the drawings to clearly and completely describe the technical solution of the present utility model with specific embodiments. It should be understood that the described embodiments are only used to illustrate the present utility model and not to limit the scope of the present utility model.

[0023] The present utility model discloses a miniaturized constant current source drive circuit, including: an input power supply, an LDO chip, a main control chip, a constant current source control chip, a drive circuit chip, a gallium nitride high electron mobility transistor (HEMT), a feedback compensation circuit, a communication chip, and an output power supply;

[0024] The LDO chip is used to convert the input voltage of the input power supply into a stable voltage, and the converted stable voltage is used to supply power to the main control chip and the drive circuit chip;

[0025] The main functions of the main control chip include: controlling the switching operation of the output power supply, monitoring the output current, and controlling the output current;

[0026] The main functions of the constant current source control chip include: monitoring the input voltage, monitoring the input current, current limiting of the output power supply, voltage limiting of the output power supply, and output of the drive voltage;

[0027] The drive circuit chip is used for the conversion of the drive voltage;

[0028] The gallium nitride high electron mobility transistor (HEMT) is used to reduce the thermal consumption of the circuit and improve the overall efficiency;

[0029] The feedback compensation circuit contains a digital potentiometer and is used to adjust and control the output current in real time.

[0030] Further, the main control chip is electrically connected to the LDO chip, the constant current source control chip, the feedback compensation circuit, and the communication chip; the constant current source control chip is electrically connected to the drive circuit chip and the feedback compensation circuit; the drive circuit chip is electrically connected to the HEMT;

[0031] Further, the input voltage of the input power supply is 30 - 70V, and the stable voltage converted by the LDO chip is 5V;

[0032] Further, the main control chip controls the switching operation of the output power supply by controlling the level, monitors the output current by collecting the output current; completes the resistance setting of the digital potentiometer through the internal bus interaction with the digital potentiometer, and then realizes the control of the output current.

[0033] Further, the main control chip realizes external communication through the interaction with the communication chip, and reports the product status using the 485 communication bus.

[0034] Further, the constant current source control chip monitors the input voltage by collecting the input voltage, so as to ensure that the voltage at the input power supply end works normally within a certain range; completes the limitation of the output maximum current and the highest voltage through the pin configuration. Once the current limiting or voltage limiting condition is triggered, the output is immediately stopped and enters the power-off state, realizing the current limit of the output power supply and the voltage limit of the output power supply;

[0035] Under the output current condition, the constant current source control chip monitors the input current by collecting the input current, ensures that the current at the input end is always controlled below the set value, and once the current limiting condition is triggered, the output is immediately stopped and enters the power-off state;

[0036] Under the condition that all states meet the requirements, the constant current source control chip outputs a PWM signal, which is used as the driving voltage for driving the subsequent power switch.

[0037] Further, the high and low levels of the PWM driving signal output by the constant current source control chip are 0 - 10V, and the high and low levels of the HEMT driving voltage used at the back end should be 0 - 5V; the drive circuit chip is used to adjust the driving voltage from 0 - 10V to 0 - 5V on the premise that the control logic remains unchanged.

[0038] Further, the feedback compensation circuit collects, filters, and amplifies the output current, compares it with the reference voltage, and feeds the comparison result back to the constant current source control chip to realize the real-time adjustment and control of the output current.

[0039] Furthermore, the high thermal conductivity of the gallium nitride high electron mobility transistor (HEMT) helps to more effectively dissipate the heat generated during the operation of the device, improving the thermal stability and reliability of the system.

[0040] In summary, the present utility model sets the output current through the communication interface. The main control chip adjusts the resistance of the digital potentiometer in the feedback compensation circuit, thereby adjusting the voltage at the compensation terminal in the constant current source control chip, and finally realizing the controllable adjustment of the output current. At the same time, the output status is monitored by the voltage acquisition loop and the current acquisition loop to ensure that the output is promptly turned off when an abnormality occurs, reducing the adverse effects of the abnormality on the input power supply and the load.

[0041] The above are only the preferred embodiments of the present utility model and are not used to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A miniaturized constant current source driving circuit, characterized in that: include: Input power supply, LDO chip, main control chip, constant current source control chip, drive circuit chip, GaN high electron mobility transistor (HEMT), feedback compensation circuit, communication chip and output power supply; The LDO chip is used to convert the input voltage of the input power supply into a stable voltage, and the converted stable voltage is used to power the main control chip and the drive circuit chip; The main functions of the main control chip include: controlling the switching operation of the output power supply, monitoring the output current, and controlling the output current; The main functions of the constant current source control chip include: input voltage monitoring, input current monitoring, output power current limiting, output power voltage limiting and output of driving voltage; The driving circuit chip is used for converting the driving voltage; The gallium nitride high electron mobility transistor (HEMT) is used to reduce circuit heat consumption and improve overall efficiency; The feedback compensation circuit includes a digital potentiometer for adjusting and controlling the output current in real time.

2. The miniaturized constant current source driving circuit according to claim 1, characterized in that: The main control chip is electrically connected to the LDO chip, the constant current source control chip, the feedback compensation circuit, and the communication chip; the constant current source control chip is electrically connected to the drive circuit chip and the feedback compensation circuit; and the drive circuit chip is electrically connected to the HEMT.

3. The miniaturized constant current source driving circuit according to claim 1, characterized in that: The input voltage of the input power supply is 30-70V, and the stable voltage after conversion by the LDO chip is 5V.

4. The miniaturized constant current source driving circuit according to claim 1, characterized in that: The main control chip controls the switching operation of the output power supply by controlling the electrical level, and monitors the output current by collecting the output current; and completes the resistance setting of the digital potentiometer by interacting with the internal bus between the digital potentiometer, thereby realizing the control of the output current.

5. The miniaturized constant current source driving circuit according to claim 1, characterized in that: The main control chip realizes external communication through interaction with the communication chip, and uses the 485 communication bus to report the product status.

6. The miniaturized constant current source driving circuit according to claim 1, characterized in that: The constant current source control chip monitors the input voltage by collecting the input voltage, thereby ensuring that the voltage at the input power supply end is within a certain range to work normally; the maximum output current and the maximum voltage are limited by the configuration of the pins. Once the current limiting or voltage limiting condition is triggered, the output is immediately stopped and the power-off state is entered, thereby achieving the current limiting of the output power supply and the voltage limiting of the output power supply; Under the output current working condition, the constant current source control chip monitors the input current by collecting the input current, ensuring that the current at the input end is always controlled below the set value. Once the current limiting condition is triggered, the output is immediately stopped and the power-off state is entered; When all conditions are met, the constant current source control chip outputs a PWM signal as a driving voltage for driving subsequent power device switches.

7. The miniaturized constant current source driving circuit according to claim 1, characterized in that: The high and low levels of the PWM drive signal output by the constant current source control chip are 0-10V respectively, and the high and low levels of the HEMT drive voltage used in the back end should be 0-5V; the drive circuit chip is used to adjust the drive voltage from 0-10V to 0-5V under the premise that the control logic remains unchanged.

8. The miniaturized constant current source driving circuit according to claim 1, characterized in that: The feedback compensation circuit collects, filters and amplifies the output current, compares it with the reference voltage, and feeds the comparison result back to the constant current source control chip to achieve real-time adjustment and control of the output current.

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