Freewheeling detection circuit

Abstract

The utility model discloses a follow current detection circuit. The circuit comprises a first switch unit, a follow current module, a load and a detection module, the first end of the load is connected with the power supply. The second end of the load is grounded. The first switch unit is connected in series with the follow current module and then connected in parallel with the load; the first end of the detection module is connected with the first switch unit, and the second end of the detection module is connected with the power supply or grounded; the first switch unit is used for controlling the connection state of the follow current module so as to enable the follow current module to carry out follow current or detection. According to the technical scheme provided by the utility model, the first switch unit is connected in series with the follow current module and then is connected in parallel with the load to form a follow current loop; one end of the detection module is connected with the first switch unit, and the other end is grounded or connected with a power supply to form a detection loop. By controlling the connection state of the first switch unit, the follow current of the load is realized, or the follow current module is detected, so that circuit damage caused by the fault of the follow current module is avoided.

Description

Technical Field

[0001] This utility model relates to the field of electrical component testing technology, and in particular to a freewheeling detection circuit. Background Technology

[0002] In some power drive circuits, electrical components are typically used for passive freewheeling. If these freewheeling components fail, or if the freewheeling circuit connection malfunctions, the freewheeling loop for the entire power circuit will be lost. This can easily lead to the breakdown of electrical components in the power drive circuit, resulting in permanent damage to the power drive circuit. Utility Model Content

[0003] This invention provides a freewheeling detection circuit to detect whether the freewheeling electrical components are functioning properly, thereby preventing damage to the drive circuit due to a fault in the freewheeling electrical components before the drive circuit is turned on.

[0004] According to one aspect of the present invention, a freewheeling detection circuit is provided, comprising: a first switching unit, a freewheeling module, a load, and a detection module;

[0005] The first end of the load is connected to the power supply, and the second end of the load is grounded;

[0006] The first switching unit is connected in series with the freewheeling module and then connected in parallel with the load;

[0007] The first end of the detection module is connected to the first switching unit, and the second end of the detection module is connected to the power supply, or the second end of the detection module is grounded.

[0008] The first switching unit is used to control the connection status of the current continuing module, so that the current continuing module can perform current continuing or detection.

[0009] Optionally, the detection module includes a detection unit, an analog-to-digital conversion unit, and a current limiting unit;

[0010] The first end of the current limiting unit is connected to the first switching unit, and the second end of the current limiting unit is connected to the power supply, or the second end of the current limiting unit is grounded.

[0011] One end of the analog-to-digital conversion unit is connected to the current limiting unit, and the other end of the analog-to-digital conversion unit is connected to the detection unit. The detection unit is used to detect the current value obtained by the analog-to-digital conversion unit.

[0012] Optionally, a second switching unit may also be included;

[0013] The first terminal of the second switching unit is connected to the second terminal of the load, the second terminal of the second switching unit is grounded, and the control terminal of the second switching unit is connected to a control signal.

[0014] Optionally, the first end of the continuous current module is connected to the second end of the load;

[0015] The second terminal of the freewheeling module is connected to the control terminal of the first switching unit, the first terminal of the first switching unit is connected to the power supply, and the second terminal of the first switching unit is grounded.

[0016] Optionally, a third switching unit may also be included;

[0017] The first terminal of the third switching unit is connected to the power supply, the second terminal of the third switching unit is connected to the first terminal of the load, and the control terminal of the third switching unit is connected to a control signal.

[0018] Optionally, the second end of the continuous current module is connected to the first end of the load;

[0019] The first end of the freewheeling module is connected to the control end of the first switching unit, the first end of the first switching unit is grounded, and the second end of the first switching unit is connected to the power supply.

[0020] Optionally, the second switching unit includes a transistor, a MOSFET, or an IGBT.

[0021] Optionally, the third switching unit includes a transistor, a MOS, or an IGBT, and the freewheeling module includes a diode.

[0022] Optionally, the current limiting unit includes a resistor.

[0023] Optionally, the load includes an inductive element.

[0024] The technical solution provided by this utility model embodiment connects a first switching unit and a freewheeling module in series and then connects them in parallel with the load to form a freewheeling circuit. A detection module is connected at one end to the first switching unit and at the other end to ground or connected to a power supply to form a detection circuit. By controlling the connection state of the first switching unit, the freewheeling module can be controlled to provide freewheeling to the load or to detect the freewheeling module, thereby preventing circuit damage due to freewheeling module failure.

[0025] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this utility model, nor is it intended to limit the scope of this utility model. Other features of this utility model will become readily apparent from the following description. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 A schematic diagram of a freewheeling detection circuit provided in an embodiment of this utility model;

[0028] Figure 2 A schematic diagram of another freewheeling detection circuit provided in this embodiment of the utility model;

[0029] Figure 3 A schematic diagram of another freewheeling detection circuit provided in this embodiment of the utility model;

[0030] Figure 4 A schematic diagram of another freewheeling detection circuit provided in this embodiment of the utility model;

[0031] Figure 5 This is a schematic diagram of another freewheeling detection circuit provided in an embodiment of the present utility model. Detailed Implementation

[0032] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0033] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0034] Figure 1A schematic diagram of a freewheeling detection circuit provided in an embodiment of this utility model; Figure 2 This is a schematic diagram of another freewheeling detection circuit provided in an embodiment of the present utility model. (See attached diagram.) Figure 1 and Figure 2 As shown, the freewheeling detection circuit includes: a first switching unit 100, a freewheeling module 200, a load 300, and a detection module 400; the first terminal of the load 300 is connected to the power supply 10, and the second terminal of the load 300 is grounded to GND; the first switching unit 100 and the freewheeling module 200 are connected in series and then connected in parallel with the load 300; the first terminal of the detection module 400 is connected to the first switching unit 100, and the second terminal of the detection module 400 is connected to the power supply 10, or the second terminal of the detection module 400 is grounded to GND; the first switching unit 100 is used to control the connection state of the freewheeling module 200 so that the freewheeling module 200 can perform freewheeling or detection.

[0035] Specifically, the load 300 is positioned between the power supply 10 and ground GND to form the main drive circuit. The first switching unit 100 and the freewheeling module 200 are connected in series and then in parallel to the two ends of the load 300, thereby forming a freewheeling circuit for the load 300 between the power supply 10, the first switching unit 100, the freewheeling module 200, and ground GND. The detection module 400 can be connected to the power supply or grounded according to the configuration of the first switching unit 100 and the freewheeling module 200, thereby forming a detection circuit for detecting the freewheeling module 200. Figure 1 As shown, in one configuration, one end of the freewheeling module 200 is grounded to GND, and the other end is connected to the control terminal of the first switching unit 100. The first end of the first switching unit 100 is connected to the power supply 10, forming a freewheeling loop. The second end of the first switching unit 100 is connected to the first end of the detection module 400, and the second end of the detection module 400 is grounded to GND, thereby forming a detection loop for detecting the freewheeling module 200 between the power supply 10, the load 300, the freewheeling module 200, the first switching unit 100, the detection module 400, and ground GND. Figure 2As shown, in another configuration, one end of the freewheeling module 200 is connected to the power supply 10, and the other end is connected to the control terminal of the first switching unit 100. The first terminal of the first switching unit 100 is grounded (GND), forming a freewheeling loop. The second terminal of the first switching unit 100 is connected to the first terminal of the detection module 400, and the second terminal of the detection module 400 is connected to another power supply 11, thereby forming a detection loop for detecting the freewheeling module 200 between the power supply 11, the detection module 400, the first switching unit 100, the freewheeling module 200, the load 300, and ground (GND). The control terminal of the first switching unit 100 is connected to the freewheeling module 200. By controlling the connection state of the control terminal of the first switching unit 100 with the first terminal or with the second terminal, the freewheeling module 200 is controlled to be in a freewheeling working state or detected. For example, the first switching unit 100 can be a single-pole double-throw switch. When the control terminal of the first switching unit 100 is connected to the second terminal, the detection circuit is activated to detect the freewheeling module. When the control terminal of the first switching unit 100 is connected to the first terminal, the freewheeling circuit is activated, and the main drive circuit of the freewheeling module provides auxiliary freewheeling.

[0036] The technical solution provided by this utility model embodiment connects a first switching unit and a freewheeling module in series and then connects them in parallel with the load to form a freewheeling circuit. A detection module is connected at one end to the first switching unit and at the other end to ground or connected to a power supply to form a detection circuit. By controlling the connection state of the first switching unit, the freewheeling module can be controlled to provide freewheeling to the load or to detect the freewheeling module, thereby preventing circuit damage due to freewheeling module failure.

[0037] Optionally, Figure 3 A schematic diagram of another freewheeling detection circuit provided in this embodiment of the utility model. Based on the above embodiments, see... Figure 3 The detection module 400 includes a detection unit 410, an analog-to-digital converter 420, and a current-limiting unit 430. The first end of the current-limiting unit 430 is connected to the first switching unit 100, and the second end of the current-limiting unit 430 is grounded to GND. One end of the analog-to-digital converter 420 is connected to the current-limiting unit 430, and the other end of the analog-to-digital converter 420 is connected to the detection unit 410. The detection unit 410 is used to detect the current value obtained by the analog-to-digital converter 420.

[0038] Specifically, with Figure 1 Taking the configuration of the detection module 400 as an example, the first end of the current limiting unit 430 is connected to the first switching unit 100, and the second end of the current limiting unit 430 is grounded to GND, thus connecting the current limiting unit 430 in series in the detection circuit. Figure 2In the configuration of the detection module 400, the first end of the current limiting unit 430 is connected to the first switching unit 100, and the second end of the current limiting unit 430 can be connected to the power supply 11. Connecting the current limiting unit 430 in series in the detection circuit prevents excessive current in the detection circuit, avoiding any impact on the freewheeling module 200. The current limiting unit 430 can be a resistor R1. One end of the analog-to-digital converter 420 is connected to the current limiting unit 430 to obtain the current value in the detection circuit and convert the analog signal into a digital signal, transmitting it to the detection unit 410 to determine if the freewheeling module 200 is faulty. For example, the detection unit 410 can be an MCU (Microcontroller Unit). The detection unit 410 can internally store a current threshold. When fault detection is performed on the freewheeling module 200, if the current value in the detection circuit exceeds the current threshold, the detection unit 410 determines that the freewheeling module 200 is faulty. The current threshold can be set according to the parameters of the current limiting unit 430.

[0039] Optionally, Figure 4 A schematic diagram of another freewheeling detection circuit provided in this embodiment of the utility model. Based on the above embodiments, see... Figure 4 The freewheeling detection circuit also includes a second switching unit 500; the first terminal of the second switching unit 500 is connected to the second terminal of the load 300, the second terminal of the second switching unit 500 is grounded, and the control terminal of the second switching unit 500 is connected to the control signal VREF1.

[0040] Specifically, the second switching unit 500 is suitable for circuits driven by low-side drive. The second switching unit 500 is connected in series between the load 300 and ground GND, thereby controlling the on / off state of the main drive circuit containing the load 300 according to the control signal VREF1. For example, the second switching unit 500 can be an NMOS (Metal-Oxide-Semiconductor-Field-Effect Transistor). The gate of the MOS transistor is connected to the control signal VREF1, the source of the MOS transistor is grounded to GND, and the drain of the MOS transistor is connected to the load 300. When the control signal VREF1 is high, the second switching unit 500 is turned on, thereby turning on the main drive circuit containing the load 300.

[0041] Alternatively, based on the above embodiments, see... Figure 4 The first end of the freewheeling module 200 is connected to the second end of the load 300; the second end of the freewheeling module 200 is connected to the control end of the first switching unit 100, the first end of the first switching unit 100 is connected to the power supply, and the second end of the first switching unit is grounded.

[0042] Specifically, the freewheeling module 200 can be a diode D. The cathode of diode D is connected to the control terminal of the first switching unit 100, and the anode of diode D is grounded to GND. The first terminal of the first switching unit 100 is connected to the power supply 10, and the second terminal of the first switching unit 100 is connected to the detection module 400 in series and then grounded. When the first terminal of the first switching unit 100 is connected to the control terminal, diode D can provide freewheeling for the load 300 and the second switching unit 500 in the main drive circuit; when the second terminal of the first switching unit 100 is connected to the control terminal, the detection module 400 performs fault detection on diode D. When an open circuit is detected in diode D, the second switching unit 500 is de-conducted via the control signal VREF1 to prevent damage to the load 300 and the second switching unit 500 caused by the open circuit of diode D.

[0043] Optionally, Figure 5 A schematic diagram of another freewheeling detection circuit provided in this embodiment of the utility model. Based on the above embodiments, see... Figure 5 The freewheeling detection circuit also includes a third switching unit 600; the first terminal of the third switching unit 600 is connected to the power supply 10, the second terminal of the third switching unit 600 is connected to the first terminal of the load 300, and the control terminal of the third switching unit 600 is connected to the control signal VREF2.

[0044] Specifically, a third switching unit 600 is connected in series between the power supply 10 and the load 300, thereby controlling the on and off states of the main drive circuit containing the load 300 according to the control signal VREF2. For example, the third switching unit 600 can be a PMOS (Metal-Oxide-Semiconductor-Field-Effect Transistor). The gate of the MOS transistor is connected to the control signal VREF2, the source of the MOS transistor is connected to the power supply 10, and the drain of the MOS transistor is connected to the load 300. When the control signal VREF2 is low, the third switching unit 600 is turned on, thereby turning on the main drive circuit containing the load 300.

[0045] Alternatively, based on the above embodiments, see... Figure 5 The second end of the freewheeling module 200 is connected to the first end of the load 300; the first end of the freewheeling module 200 is connected to the control end of the first switching unit 100, the first end of the first switching unit 100 is grounded, and the second end of the first switching unit 100 is connected to the power supply 11.

[0046] Specifically, the freewheeling module 200 can be a diode D. The anode of diode D is connected to the control terminal of the first switching unit 100, and the cathode of diode D is connected to the third switching unit 600. The first terminal of the first switching unit 100 is grounded (GND), and the second terminal of the first switching unit 100 is connected to the power supply 11 after being connected in series with the detection module 400. When the first terminal of the first switching unit 100 is connected to the control terminal, diode D can provide freewheeling for the load 300 and the third switching unit 600 in the main drive circuit; when the second terminal of the first switching unit 100 is connected to the control terminal, the detection module 400 performs fault detection on diode D. When an open circuit is detected in diode D, the control signal VREF2 controls the third switching unit 600 to not conduct, preventing the open circuit of diode D from causing damage to the load 300 and the third switching unit 600.

[0047] Optionally, the second switching unit 500 includes a transistor, a MOSFET, or an IGBT.

[0048] Specifically, in other embodiments, the second switching unit 500 may also be a transistor, a MOSFET, or an IGBT. It should be noted that this embodiment does not specifically limit the type of the second switching unit 500; the switching type of the second switching unit 500 can be set according to the design of the main drive circuit and the detection module 400.

[0049] Alternatively, based on the above embodiments, see... Figure 4 and Figure 5 The third switching unit 600 includes a transistor, MOSFET, or IGBT, and the freewheeling module 200 includes a diode D.

[0050] Specifically, in other embodiments, the third switching unit 600 can also be a transistor, a MOSFET, or an IGBT. It should be noted that this embodiment does not specifically limit the type of the third switching unit 600; the switching type of the third switching unit 600 can be set according to the design of the main drive circuit and the detection module 400. The freewheeling module 200 can be a diode. When the first switching unit 100 controls the freewheeling circuit of the freewheeling module 200 to be turned on, the diode D can provide auxiliary freewheeling current to the load 300 on the main drive circuit.

[0051] Alternatively, based on the above embodiments, see... Figure 4 and Figure 5 The load 300 includes inductive elements.

[0052] Specifically, the inductive element can be an inductor L. The load 300 can be a purely inductive load L, or a load consisting of a resistor R and an inductor L. When the current in the main drive circuit suddenly changes, the inductive element of the load 300 generates a self-induced electromotive force to maintain the current flow. The self-induced electromotive force generated by the inductive element can be released through the freewheeling module 200, thereby protecting the electrical components in the main drive circuit from damage.

[0053] It should be understood that the various forms of the process shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this utility model can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this utility model can be achieved, and this is not limited herein.

[0054] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A freewheeling current detection circuit, characterized in that, include: First switching unit, freewheeling module, load and detection module; The first end of the load is connected to the power supply, and the second end of the load is grounded; The first switching unit is connected in series with the freewheeling module and then connected in parallel with the load; The first end of the detection module is connected to the first switching unit, and the second end of the detection module is connected to the power supply, or the second end of the detection module is grounded. The first switching unit is used to control the connection status of the current continuing module, so that the current continuing module can perform current continuing or detection.

2. The freewheeling detection circuit according to claim 1, characterized in that, The detection module includes a detection unit, an analog-to-digital conversion unit, and a current limiting unit; The first end of the current limiting unit is connected to the first switching unit, and the second end of the current limiting unit is connected to the power supply, or the second end of the current limiting unit is grounded. One end of the analog-to-digital conversion unit is connected to the current limiting unit, and the other end of the analog-to-digital conversion unit is connected to the detection unit. The detection unit is used to detect the current value obtained by the analog-to-digital conversion unit.

3. The freewheeling detection circuit according to claim 1, characterized in that, It also includes a second switching unit; The first terminal of the second switching unit is connected to the second terminal of the load, the second terminal of the second switching unit is grounded, and the control terminal of the second switching unit is connected to a control signal.

4. The freewheeling detection circuit according to claim 3, characterized in that, The first end of the continuous current module is connected to the second end of the load; The second terminal of the freewheeling module is connected to the control terminal of the first switching unit, the first terminal of the first switching unit is connected to the power supply, and the second terminal of the first switching unit is grounded.

5. The freewheeling detection circuit according to claim 1, characterized in that, It also includes a third switching unit; The first terminal of the third switching unit is connected to the power supply, the second terminal of the third switching unit is connected to the first terminal of the load, and the control terminal of the third switching unit is connected to a control signal.

6. The freewheeling detection circuit according to claim 5, characterized in that, The second end of the continuous current module is connected to the first end of the load; The first end of the freewheeling module is connected to the control end of the first switching unit, the first end of the first switching unit is grounded, and the second end of the first switching unit is connected to the power supply.

7. The freewheeling detection circuit according to claim 3 or 4, characterized in that, The second switching unit includes a transistor, a MOSFET, or an IGBT.

8. The freewheeling detection circuit according to claim 5 or 6, characterized in that, The third switching unit includes a transistor, a MOS, or an IGBT, and the freewheeling module includes a diode.

9. The freewheeling detection circuit according to claim 2, characterized in that, The current limiting unit includes a resistor.

10. The freewheeling detection circuit according to claim 1, characterized in that, The load includes an inductive element.

Images