Circuit and method for detecting short and open circuit of a load using a diode combination circuit

Abstract

The application discloses a circuit for detecting short circuit and open circuit of a load by using a diode combination circuit. One end of the load is connected with a power supply, and the other end of the load is connected with a detection circuit. The detection circuit comprises a diode, a sampling resistor, a first voltage sampling end and a second voltage sampling end. One end of the diode and the sampling resistor in series is connected with the other end of the load, and the other end of the diode and the sampling resistor in series is grounded. The first voltage sampling end is connected with the other end of the load, and the second voltage sampling end is connected between the diode and the sampling resistor. The application further discloses a detection method and an electronic device comprising the circuit for detecting short circuit and open circuit of a load by using a diode combination circuit. The application uses the voltage-current characteristic curve of the diode to detect the short circuit and the open circuit of the load by using the combination circuit of the diode and the sampling resistor, thereby ensuring the accuracy of the detection.

Description

Technical Field

[0001] This invention relates to the field of load detection technology, specifically to a circuit and method for detecting load short circuits and open circuits using a diode combination circuit, which is particularly suitable for open circuit detection in low-current load circuits. Background Technology

[0002] In electronic circuits, pluggable external load devices are frequently used. The method of detecting the current in the load device using a sampling resistor to determine whether the load device is short-circuited or open-circuited is widely used. Please refer to... Figure 1 As shown, it detects the sampling resistor R 20 The high-side voltage is used to determine whether the load is short-circuited or open-circuited, where the resistance R 10 For filtering resistors, capacitor C 10 The capacitor and the filter capacitor together form a filter circuit. The voltage sampling terminal ADC can be the I / O port of a microcontroller or other chip that can receive voltage signals, such as the ADC port.

[0003] exist Figure 1 In the middle, the load R L The current flowing through it passes through the current sampling resistor R. 20 A certain voltage drop is generated, the voltage value of which is:

[0004] V=R 20 *I L (Equation 1)

[0005] Where V is the current sampling resistor R 20 The voltage drop across the two ends, i.e., the voltage value acquired by the ADC at the voltage sampling terminal, R 20 For current sampling resistor R 20 The resistance value, I L For the flow through load R L Or current sampling resistor R 20 The current value. Through R 10 and C 10 After low-pass filtering, the signal is amplified by an amplifier circuit, and then sampled by a microcontroller's ADC to calculate I. L Current, through I L The current value can be used to determine whether the equipment is open-circuited and whether it is working properly.

[0006] The advantage of the above detection circuit is that detection can be completed through a single ADC port. The disadvantage is that when the operating current range of the load device is too wide, and the ratio of the maximum current to the minimum current reaches hundreds or even thousands of times, detection errors are common.

[0007] For example, assuming a sampling resistor of 0.05 ohms, a maximum load current of 1A, a minimum load current of 1mA, and an amplifier factor of 50, when the maximum load current is 1A, the sampled output voltage is 2.5V (the voltage received by the ADC at the voltage sampling terminal is 2.5V). In this case, i.e., in a high-current load scenario, the current sampling resistor R can be used to sample the voltage. 20 The high-side voltage is used to determine whether the load is short-circuited or open-circuited.

[0008] In low-current load scenarios, such as a load current of 10mA, the sampling output is only 25mV. Such a small voltage is easily affected by interference during detection, leading to detection errors.

[0009] Therefore, using the above-mentioned traditional detection circuit for pluggable load open circuit and current detection has the following drawbacks: if the load is operating at a low current, judging by only sampling the current through a resistor is easy to be affected by interference and cause false detection. Summary of the Invention

[0010] To overcome the shortcomings of the prior art, the present invention aims to provide a circuit and electronic device for detecting short circuits and open circuits in a load using a diode combination circuit. It utilizes the volt-ampere characteristic curve of the diode and a combination circuit of the diode and a sampling resistor to detect short circuits and open circuits in the load, ensuring the accuracy of the detection.

[0011] The first aspect of this invention provides a circuit for detecting short circuits and open circuits in a load using a diode combination circuit. One end of the load is connected to a power supply, and the other end of the load is connected to a detection circuit. The detection circuit includes a diode, a sampling resistor, a first voltage sampling terminal, and a second voltage sampling terminal. One end of the diode and the sampling resistor connected in series is connected to the other end of the load, and the other end of the diode and the sampling resistor connected in series is grounded. The first voltage sampling terminal is connected to the other end of the load, and the second voltage sampling terminal is connected between the diode and the sampling resistor. The voltage signal collected by the first voltage sampling terminal is recorded as a first voltage value, and the voltage signal collected by the second voltage sampling terminal is recorded as a second voltage value. The first voltage value and the second voltage value are used to determine whether the load is short-circuited or open-circuited.

[0012] In a preferred embodiment, in the first aspect of the present invention, the detection circuit further includes a first filter resistor, a second filter resistor, a first filter capacitor, and a second filter capacitor; one end of the first filter resistor is connected to the other end of the load, the other end of the first filter resistor is connected to the first voltage sampling terminal, one end of the first filter capacitor is connected between the first filter resistor and the first voltage sampling terminal, and the other end of the first filter capacitor is grounded; one end of the second filter resistor is connected between the diode and the sampling resistor, the other end of the second filter resistor is connected to the second voltage sampling terminal, one end of the second filter capacitor is connected between the second filter resistor and the second voltage sampling terminal, and the other end of the second filter capacitor is grounded.

[0013] In a preferred embodiment, in a first aspect of the present invention, the anode of the diode is connected to the other end of the load, and the cathode of the diode is grounded through the sampling resistor; or, the anode of the diode is connected to the other end of the load through the sampling resistor, and the cathode of the diode is grounded.

[0014] As a preferred embodiment, in the first aspect of the present invention, the circuit for detecting load short circuits and open circuits using a diode combination circuit further includes a plug-in structure. The plug-in structure includes a first connector and a second connector. The first connector has a first connection terminal and a second connection terminal. The second connector has a third connection terminal and a fourth connection terminal. The power supply is connected to the first connection terminal. The detection circuit is connected to the second connection terminal. The two ends of the load are respectively connected to the third connection terminal and the fourth connection terminal. When the first connector and the second connector are plugged in, the first connection terminal and the third connection terminal are electrically connected, and the second connection terminal and the fourth connection terminal are electrically connected.

[0015] The second aspect of this invention discloses a method for detecting load short circuits and open circuits using a diode combination circuit as described in the first aspect of this invention, comprising the following steps:

[0016] The first voltage value and the second voltage value collected by the first voltage sampling terminal and the second voltage sampling terminal are respectively acquired;

[0017] The first voltage value is used to determine whether the load is short-circuited.

[0018] Whether the load is open-circuited is determined by the second voltage value or the difference between the first voltage value and the second voltage value.

[0019] As a preferred embodiment, in a second aspect of the present invention, determining whether the load is open-circuited by the difference between the second voltage value and the first voltage value and the second voltage value includes:

[0020] When the anode of the diode is connected to the other end of the load and the cathode of the diode is grounded through the sampling resistor, if the difference between the first voltage value and the second voltage value is greater than or equal to the first preset threshold, the load is not an open circuit; if the difference between the first voltage value and the second voltage value is less than the first preset threshold, the load is an open circuit.

[0021] When the anode of the diode is connected to the other end of the load through a sampling resistor and the cathode of the diode is grounded, if the second voltage value is greater than or equal to the first preset threshold, the load is not an open circuit; if the second voltage value is less than the first preset threshold, the load is an open circuit.

[0022] As a preferred embodiment, in a second aspect of the present invention, determining whether the load is short-circuited based on the first voltage value includes:

[0023] When the first voltage value is equal to the power supply voltage, the load is short-circuited;

[0024] When the first voltage value is less than the power supply voltage, the load is not short-circuited.

[0025] In a preferred embodiment, in a second aspect of the present invention, the method further includes: determining whether the load is overcurrent by sampling the voltage value across the sampling resistor.

[0026] As a preferred embodiment, in a second aspect of the present invention, determining whether the load is overcurrent by sampling the voltage value across the resistor includes:

[0027] When the anode of the diode is connected to the other end of the load and the cathode of the diode is grounded through the sampling resistor, if the quotient obtained by dividing the second voltage value by the resistance value of the sampling resistor is greater than or equal to the second preset threshold, then the load is overcurrent; otherwise, the load is not overcurrent.

[0028] When the anode of the diode is connected to the other end of the load through a sampling resistor and the cathode of the diode is grounded, if the quotient obtained by dividing the difference between the first voltage value and the second voltage value by the resistance value of the sampling resistor is greater than or equal to the second preset threshold, then the load is overcurrent; otherwise, the load is not overcurrent.

[0029] A third aspect of the present invention provides an electronic device that includes the circuit described in the first aspect of the present invention, which uses a diode combination circuit to detect load short circuits and open circuits.

[0030] Compared to existing technologies, the embodiments of the present invention use a combined circuit composed of diodes and sampling resistors to detect open circuits and short circuits in the load. It is particularly suitable for low-current scenarios. By utilizing the nonlinearity of the forward voltage drop and forward current of the diode, the forward voltage of the diode can effectively determine whether the load is open-circuited, thus ensuring the accuracy of open-circuit detection. Attached Figure Description

[0031] Figure 1 Schematic diagram of an open-circuit or short-circuit detection circuit for an existing load;

[0032] Figure 2 This is a schematic diagram of the circuit for detecting load short circuits and open circuits using a diode combination circuit according to Embodiment 1 of the present invention.

[0033] Figure 3 This is a circuit diagram illustrating the detection of load short circuits and open circuits using a diode combination circuit according to Embodiment 2 of the present invention.

[0034] Figure 4 This is the current-voltage characteristic curve of the diode;

[0035] Figure 5 This is a flowchart illustrating the method for detecting load short circuits and open circuits using a diode combination circuit according to Embodiment 3 of the present invention. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 are within the scope of protection of the present invention.

[0037] It should be noted that the terms "first," "second," "third," "fourth," etc., in the specification and claims of this invention are used to distinguish different objects, not to describe a specific order. The terms "comprising" and "having," and any variations thereof, in the embodiments of this invention are intended to cover non-exclusive inclusion. Exemplarily, a process, method, system, product, or device that includes 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 these processes, methods, products, or devices.

[0038] Example 1

[0039] Please refer to Figure 2As shown, a circuit for detecting short circuits and open circuits in a load using a diode combination circuit is described. One end of the load is connected to a power supply, and the other end of the load is connected to a detection circuit. The detection circuit includes a diode D1, a sampling resistor R3, a first voltage sampling terminal ADC1, and a second voltage sampling terminal ADC2.

[0040] In Embodiment 1 of the present invention, a diode is placed between the load and the sampling resistor, that is, the anode of the diode is connected to the other end of the load, and the cathode of the diode is grounded through the sampling resistor; the first voltage sampling terminal is connected to the other end of the load, and the second voltage sampling terminal is connected between the diode and the sampling resistor. The voltage signal collected by the first voltage sampling terminal is recorded as the first voltage value, and the voltage signal collected by the second voltage sampling terminal is recorded as the second voltage value. The first voltage value and the second voltage value are used to determine whether the load is short-circuited or open-circuited.

[0041] The first voltage sampling terminal ADC1 and the second voltage sampling terminal ADC2 can be two ADC ports of a microcontroller. Two voltages can be detected through the two ADC ports of the microcontroller, namely the high-side voltage of the diode and the high-side voltage of the sampling resistor, which are denoted as the first voltage value Vol1 and the second voltage value Vol2, respectively.

[0042] At this time, the voltage Vr across the sampling resistor is:

[0043] Vr=Vol2-0 (Equation 2) The voltage Vd across the diode is:

[0044] Vd = Vol1 – Vol2 (Equation 3) The sampling resistor R3 samples the load current, and the load current I L for:

[0045] I L =Vr / R3 (Equation 4)

[0046] Overcurrent detection: using I L Overcurrent detection can be performed on the load when I L When the quotient (the second voltage value divided by the resistance of the sampling resistor) is greater than or equal to the second preset threshold, the overcurrent detection of the load is considered as overcurrent. The second preset threshold is set according to the maximum current of the load.

[0047] Short-circuit detection: During short-circuit detection, the power supply is directly grounded through the diode and sampling resistor. Therefore, whether the load is short-circuited can be determined by detecting the high-side voltage of the diode. That is, the load is short-circuited based on a first voltage value. If the load is short-circuited, the first voltage value will be equal to the power supply voltage; otherwise, if the first voltage value is less than the power supply voltage, the load is generally considered not to be short-circuited. In some other cases, considering the effect of line resistance, the first voltage value can also be slightly less than the power supply voltage. For example, a third preset threshold can be used, which is slightly less than the power supply voltage. If the first voltage value is greater than or equal to this third preset threshold, the load can be considered short-circuited. Alternatively, I... L Short circuit detection can be performed on the load when I L If the current is greater than or equal to the set current threshold, the load is determined to be short-circuited.

[0048] Open-circuit detection typically involves determining whether a load is open-circuited by sampling the voltage across a resistor; that is, judging whether the second voltage value is zero. However, in some low-current load scenarios, such as the example mentioned in the background section, the second voltage value is very small, and this small value is easily affected by interference, leading to inaccurate detection.

[0049] There are two possibilities for the interference here. One is that the microcontroller's ADC2 port may not detect the voltage value. The other is that even if a very small voltage value is detected, it cannot be determined whether it is the actual voltage value across the sampling resistor or a voltage generated by the circuit due to other influences. For example, when the load is open-circuited, the second voltage value may also be a very small value. In this case, the load is considered not to be open-circuited.

[0050] In a preferred embodiment of the present invention, the current-voltage characteristic curve of a diode is utilized, and the forward voltage drop and forward current of the diode are nonlinear.

[0051] like Figure 3 As shown, when the load current is 1A, the forward voltage drop of the diode at 25℃ is approximately 0.41V; when the load current is 0.01A, the forward voltage drop of the diode at 25℃ is approximately 0.11V; the forward voltage of the diode is only 0 when the load is completely turned off (open circuit) and the load current approaches zero.

[0052] With the introduction of diode detection, it is no longer necessary to determine whether the load is open-circuited based on the voltage across the sampling resistor. Instead, the forward voltage drop of the diode is used to determine the open-circuit status of the load. If the difference between the first voltage value and the second voltage value (i.e., the forward voltage drop of the diode) is greater than or equal to a first preset threshold, the load is not open-circuited. If the difference between the first voltage value and the second voltage value is less than the first preset threshold, the load is open-circuited.

[0053] The first preset threshold is selected based on the diode's characteristics. Generally, it's chosen as the forward voltage drop of the diode under low current conditions, or a voltage value smaller than that. For example, the first preset threshold could be 0.11V or 0.10V. In low-current scenarios, the forward voltage drop of the diode is tens or even hundreds of times larger than the very small voltage across the sampling resistor. In this case, it significantly reduces false positives in load open-circuit detection.

[0054] Meanwhile, this detection circuit is fully applicable to the short-circuit and open-circuit detection process of high-current loads. For high-current load circuits, the first preset threshold value can also be the first preset threshold value of this low-current scenario.

[0055] As an optional embodiment, in Embodiment 1 of the present invention, a filtering circuit can also be provided. Specifically, a first filtering circuit is provided at the first voltage sampling terminal, and this first filtering circuit includes a first filtering resistor R1 and a first filtering capacitor C1. One end of the first filtering resistor R1 is connected to the load R. L At the other end, the other end of the first filter resistor R1 is connected to the first voltage sampling terminal ADC1, one end (positive terminal) of the first filter capacitor C1 is connected between the first filter resistor R1 and the first voltage sampling terminal ADC1, and the other end (negative terminal) of the first filter capacitor C1 is grounded.

[0056] Similarly, a second filter circuit is provided at the second voltage sampling terminal. This second filter circuit includes a second filter resistor R2 and a second filter capacitor C2. One end of the second filter resistor R2 is connected between the diode D1 and the sampling resistor R3, and the other end of the second filter resistor R2 is connected to the second voltage sampling terminal ADC2. One end (positive terminal) of the second filter capacitor C2 is connected between the second filter resistor R2 and the second voltage sampling terminal ADC2, and the other end (negative terminal) of the second filter capacitor C2 is grounded.

[0057] As an application scenario, Embodiment 1 of the present invention can be applied to pluggable external load devices, that is, the connection between the load and the power supply is realized through a pluggable structure.

[0058] The plug-in structure includes a first plug J1 and a second plug J2. The first plug has a first connection terminal (pin 1 of J1) and a second connection terminal (pin 2 of J1). The second plug has a third connection terminal (pin 1 of J2) and a fourth connection terminal (pin 2 of J2).

[0059] The power supply is connected to the first connection terminal, the detection circuit is connected to the second connection terminal, and the two ends of the load are connected to the third connection terminal and the fourth connection terminal respectively; when the first connector and the second connector are plugged in, the first connection terminal and the third connection terminal are electrically connected, and the second connection terminal and the fourth connection terminal are electrically connected.

[0060] Example 2

[0061] The only difference between Example 2 and Example 1 is the change in the positions of the sampling resistor R3 and diode D1. For Example 2, please refer to... Figure 4 As shown, the anode of diode D1 is connected to the load R through sampling resistor R3. L At the other end, the cathode of diode D1 is grounded.

[0062] The sampled voltages of the first voltage sampling terminal ADC1 and the second voltage sampling terminal ADC2 are denoted as the first voltage value Vol1 and the second voltage value Vol2, respectively.

[0063] At this time, the voltage Vr across the sampling resistor is:

[0064] Vr = Vol1 – Vol2 (Equation 5) The voltage Vd across the diode is:

[0065] Vd=Vol2–0 (Equation 6) The sampling resistor R3 samples the load current, and the load current I L for:

[0066] I L =Vr / R3 (Equation 7)

[0067] Overcurrent detection: using I L Overcurrent detection can be performed on the load when I L When the quotient (the first voltage value minus the second voltage value, divided by the resistance of the sampling resistor) is greater than or equal to the second preset threshold, the overcurrent detection of the load is considered as overcurrent. The second preset threshold is set according to the maximum current of the load.

[0068] Short circuit detection: During short circuit detection, the power supply is directly grounded through the sampling resistor and diode. Therefore, the load short circuit can be determined by detecting the high-side voltage of the sampling resistor, or by using I... L The method for determining whether the load is short-circuited is similar to that in Example 1, which uses the high-side voltage of a diode to determine whether the load is short-circuited, and will not be repeated here.

[0069] Open circuit detection, as described in Example 1, cannot guarantee the accuracy of the results when the load is open-circuited by sampling resistor alone in low-current load scenarios. Therefore, in Example 2, the open circuit is still determined by the forward voltage drop of the diode, based on the principle that the forward voltage drop and forward current of the diode are non-linear.

[0070] If the second voltage value (i.e., the forward voltage drop of the diode) is greater than or equal to the first preset threshold, the load is not an open circuit; if the second voltage value is less than the first preset threshold, the load is an open circuit.

[0071] Example 3

[0072] Example 3 discloses a method for detecting load short circuits and open circuits using a diode combination circuit as described in Example 1 or Example 2. Please refer to [link / reference]. Figure 5 As shown, it may include the following steps:

[0073] S310. Determine whether the load is short-circuited by using the first voltage value.

[0074] During short-circuit detection, the power supply is directly grounded through a diode and a sampling resistor. Therefore, the first voltage value can be used to determine if the load is short-circuited. If the load is short-circuited, the first voltage value will equal the power supply voltage; otherwise, if the first voltage value is less than the power supply voltage, the load is generally considered not to be short-circuited. In some other cases, considering the influence of factors such as line resistance, the first voltage value can also be slightly less than the power supply voltage. For example, a third preset threshold can be used, which is slightly less than the power supply voltage. If the first voltage value is greater than or equal to the third preset threshold, it can be considered that the load is short-circuited. Alternatively, I... L Short circuit detection can be performed on the load when I L If the current is greater than or equal to the set current threshold, the load is determined to be short-circuited.

[0075] S320. Determine whether the diode or the sampling resistor is grounded in the detection circuit.

[0076] If the sampling resistor is grounded, steps S330 and S340 are used to determine whether the load is open-circuited and overcurrent, respectively; if the diode is grounded, steps S350 and S360 are used to determine whether the load is open-circuited and overcurrent, respectively.

[0077] When the sampling resistor is grounded, the anode of the diode is connected to the other end of the load, and the cathode of the diode is grounded through the sampling resistor.

[0078] S330: Determine whether the load is overcurrent by using the second voltage value.

[0079] Using I L Overcurrent detection can be performed on the load when I L If the quotient (the second voltage value divided by the resistance of the sampling resistor) is greater than or equal to the second preset threshold, then the overcurrent detection of the load is considered an overcurrent; otherwise, the load is not overcurrent. The second preset threshold is set according to the maximum current of the required load.

[0080] S340: Determine whether the load is open circuit by using the first voltage value and the second voltage value.

[0081] When the sampling resistor is grounded, the forward voltage drop of the diode is the difference between the first voltage value and the second voltage value. The difference between the first voltage value and the second voltage value can be used to determine whether the load is open circuit. If the difference between the first voltage value and the second voltage value is greater than or equal to the first preset threshold, the load is not open circuit. If the difference between the first voltage value and the second voltage value is less than the first preset threshold, the load is open circuit.

[0082] S350: Determine whether the load is overcurrent by using the first voltage value and the second voltage value.

[0083] Using I L Overcurrent detection can be performed on the load when I L When the quotient (the first voltage value minus the second voltage value, divided by the resistance of the sampling resistor) is greater than or equal to the second preset threshold, the overcurrent detection of the load is considered as overcurrent. The second preset threshold is set according to the maximum current of the load.

[0084] S360: Determine whether the load is open circuit by using the second voltage value.

[0085] When the diode is grounded, the forward voltage drop of the diode is the second voltage value. The second voltage value can be used to determine whether the load is open circuit. If the second voltage value is greater than or equal to the first preset threshold, the load is not open circuit. If the second voltage value is less than the first preset threshold, the load is open circuit.

[0086] Example 4

[0087] Embodiment 4 discloses an electronic device that includes the diode combination circuit disclosed in Embodiment 1 or Embodiment 2 for detecting load short circuits and open circuits. This electronic device can be any device requiring load detection, and is particularly suitable for detecting short circuits and open circuits in plug-in load scenarios. For example, this electronic device can be a load testing device, an LED driver circuit, a motor driver circuit, or a vehicle controller, etc. In addition to the diode combination circuit for detecting load short circuits and open circuits, this electronic device may also have other electrical and / or mechanical components with its own functions.

[0088] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the embodiments of the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A circuit for detecting short circuits and open circuits in a load using a diode combination circuit, wherein one end of the load is connected to a power supply, and the other end of the load is connected to a detection circuit, characterized in that, The detection circuit includes a diode, a sampling resistor, a first voltage sampling terminal, and a second voltage sampling terminal. One end of the diode and the sampling resistor connected in series is connected to the other end of the load, and the other end of the diode and the sampling resistor connected in series is grounded. The first voltage sampling terminal is connected to the other end of the load, and the second voltage sampling terminal is connected between the diode and the sampling resistor. The voltage signal collected by the first voltage sampling terminal is recorded as the first voltage value, and the voltage signal collected by the second voltage sampling terminal is recorded as the second voltage value. The first voltage value and the second voltage value are used to determine whether the load is short-circuited or open-circuited.

2. The circuit as described in claim 1, characterized in that, The detection circuit further includes a first filter resistor, a second filter resistor, a first filter capacitor, and a second filter capacitor; one end of the first filter resistor is connected to the other end of the load, the other end of the first filter resistor is connected to the first voltage sampling terminal, one end of the first filter capacitor is connected between the first filter resistor and the first voltage sampling terminal, and the other end of the first filter capacitor is grounded; one end of the second filter resistor is connected between the diode and the sampling resistor, the other end of the second filter resistor is connected to the second voltage sampling terminal, one end of the second filter capacitor is connected between the second filter resistor and the second voltage sampling terminal, and the other end of the second filter capacitor is grounded.

3. The circuit as described in claim 1, characterized in that, The anode of the diode is connected to the other end of the load, and the cathode of the diode is grounded through the sampling resistor; or, the anode of the diode is connected to the other end of the load through the sampling resistor, and the cathode of the diode is grounded.

4. The circuit as described in any one of claims 1-3, characterized in that, The circuit for detecting load short circuits and open circuits using a diode combination circuit further includes a plug-in structure. The plug-in structure includes a first connector and a second connector. The first connector has a first connection terminal and a second connection terminal. The second connector has a third connection terminal and a fourth connection terminal. The power supply is connected to the first connection terminal. The detection circuit is connected to the second connection terminal. The two ends of the load are respectively connected to the third connection terminal and the fourth connection terminal. When the first connector and the second connector are plugged in, the first connection terminal and the third connection terminal are electrically connected, and the second connection terminal and the fourth connection terminal are electrically connected.

5. A method for detecting load short circuits and open circuits using a diode combination circuit as described in any one of claims 1-4, characterized in that, It includes the following steps: The first voltage value and the second voltage value collected by the first voltage sampling terminal and the second voltage sampling terminal are respectively acquired; The first voltage value is used to determine whether the load is short-circuited. Whether the load is open-circuited is determined by the second voltage value or the difference between the first voltage value and the second voltage value.

6. The method as described in claim 5, characterized in that, Determining whether the load is open-circuited by the second voltage value or the difference between the first voltage value and the second voltage value includes: When the anode of the diode is connected to the other end of the load and the cathode of the diode is grounded through the sampling resistor, if the difference between the first voltage value and the second voltage value is greater than or equal to the first preset threshold, the load is not an open circuit; if the difference between the first voltage value and the second voltage value is less than the first preset threshold, the load is an open circuit. When the anode of the diode is connected to the other end of the load through a sampling resistor and the cathode of the diode is grounded, if the second voltage value is greater than or equal to the first preset threshold, the load is not an open circuit; if the second voltage value is less than the first preset threshold, the load is an open circuit.

7. The method as described in claim 5, characterized in that, Determining whether the load is short-circuited based on the first voltage value includes: When the first voltage value is equal to the power supply voltage, the load is short-circuited; When the first voltage value is less than the power supply voltage, the load is not short-circuited.

8. The method as described in claim 5, characterized in that, The method further includes: determining whether the load is overcurrent by sampling the voltage value across the resistor.

9. The method as described in claim 8, characterized in that, The step of determining whether the load is overcurrent by sampling the voltage across the resistor includes: When the anode of the diode is connected to the other end of the load and the cathode of the diode is grounded through the sampling resistor, if the quotient obtained by dividing the second voltage value by the resistance value of the sampling resistor is greater than or equal to the second preset threshold, then the load is overcurrent; otherwise, the load is not overcurrent. When the anode of the diode is connected to the other end of the load through a sampling resistor and the cathode of the diode is grounded, if the quotient obtained by dividing the difference between the first voltage value and the second voltage value by the resistance value of the sampling resistor is greater than or equal to the second preset threshold, then the load is overcurrent; otherwise, the load is not overcurrent.

10. An electronic device, characterized in that, It includes the circuit described in any one of claims 1-4 that uses a diode combination circuit to detect load short circuits and open circuits.

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