Socket LED indicating lamp circuit with real-time fault analysis function

Abstract

The utility model relates to the technical field of hardware circuits of vehicle-mounted power supply inverters, and discloses a socket LED indicating lamp circuit with a real-time fault analysis function, which comprises an LDO (Low Dropout Regulator) controlled by an enabling pin, a socket LED indicating lamp circuit, a temperature sampling circuit, a primary side MCU (Microprogrammed Control Unit) and an isolation communication circuit, the LDO supplies power to the primary side MCU, the socket LED indicating lamp circuit and the temperature sampling circuit in a stabilized voltage mode. According to the utility model, under the condition that an original hardware circuit is not changed, software programming is carried out through the primary side MCU, a real-time indication function of product faults is added, various protection state information of a product is modulated on the red LED indication lamp, an input voltage value can be detected in real time, and overload, short circuit, electric leakage, over-temperature and other information of an output load can be detected in real time; when relevant abnormal information is detected, the relevant abnormal information is modulated on a red LED indicator light control signal in a PWM duty ratio mode, then the red LED indicator light of the socket is controlled and lightened, and the real-time fault analysis function of a product is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of vehicle-mounted power inverter hardware circuits, in particular to a socket LED indicator light circuit with a real-time fault analysis function. Background Art

[0002] The vehicle power inverter product can invert the battery voltage of the vehicle into 220V / 50Hz AC power, and output it to the user through a 220V power socket. Among them, an LED indicator circuit is usually designed in the 220V power socket, and the user can see the status of the socket indicator when using it to confirm that the vehicle power inverter product can work normally. The LED indicator circuit of this socket usually uses a red and green two-color LED indicator for display: when the green light is continuously on, it means that the vehicle power inverter product is working normally and continuously outputs 220V / 50Hz AC power; when the red light is continuously on or flashing, it means that the product has entered the protection state of input undervoltage / overvoltage, output overload, short circuit, leakage, and overtemperature.

[0003] Since the vehicle power inverter products have many perfect protection functions, and such products are non-functional safety parts, there is no CAN or LIN communication function to report the working status in real time and store faults. When the product has no 220V / 50Hz AC output due to abnormal operation, it is basically caused by entering a certain protection state. However, the LED indicator of the socket can only show that the product has entered a protection state, and it is impossible to accurately trace what protection state the product has entered. This greatly increases the difficulty for engineers to further analyze, troubleshoot, lock and solve problems, especially when encountering some faulty parts with after-sales quality complaints, the extremely low probability of the fault phenomenon cannot be reproduced 100%, and it is difficult to troubleshoot and lock the problem. Utility Model Content

[0004] In order to solve the problem that the LED indicator of the socket used in the above existing vehicle power inverter can only show that the product has entered a protection state, but cannot accurately trace what protection state the product has entered, and the difficulty of engineers in analyzing, troubleshooting, locking and solving the problem is great, the utility model is implemented through the following technical solutions: a socket LED indicator circuit with real-time fault analysis function, including an LDO with enable pin control, a socket LED indicator circuit, a temperature sampling circuit, a primary side MCU, and an isolation communication circuit. The LDO is a low voltage difference linear regulator, and its structure mainly includes a startup circuit, a constant current source bias unit, an enable circuit, and an adjustment element. , reference source, the basic working principle of LDO is: when the system is powered on, if the enable pin is at a high level, the circuit starts to start, the constant current source circuit provides bias for the entire circuit, the reference source voltage is quickly established, and the output continues to rise with the input. When the output is about to reach the specified value, the output feedback voltage obtained by the feedback network is also close to the reference voltage value; at this time, the error amplifier amplifies the small error signal between the output feedback voltage and the reference voltage, and then amplifies it to the output through the adjustment tube, thereby forming negative feedback, ensuring that the output voltage is stable at the specified value. Similarly, if the input voltage changes or the output current changes, this closed loop will keep the output voltage unchanged. The low-dropout linear regulator also has functions such as load short-circuit protection, overvoltage shutdown, overheating shutdown, and reverse connection protection. The primary-side MCU is a microcontroller unit, which is a software-programmable chip. Its model is S9KEAZN8AVTG;

[0005] The LDO provides 5V regulated power supply for the primary side MCU, the socket LED indicator circuit and the temperature sampling circuit. The red and green LED indicators in the socket LED indicator circuit are installed in the power socket to indicate the working status of the inverter in real time.

[0006] The primary-side MCU detects and obtains the input power supply voltage, temperature, overload, short circuit and leakage information of the inverter in real time through its own AD sampling port and isolated communication circuit, and controls the red and green light display of the socket LED indicator.

[0007] By using the primary-side MCU for software programming and adding a real-time indication function for product faults, the various protection status information of the product can be modulated on the red LED indicator light. This allows the product's real-time fault analysis function to be realized without affecting the original function of the red LED indicator light on the power socket.

[0008] Furthermore, the input of the LDO is connected to the input power supply, and the output is connected to the VCC pin of the primary side MCU, the socket LED indicator circuit and the temperature sampling circuit.

[0009] Furthermore, the socket LED indicator circuit is composed of R1 and a red LED connected in series, and R2 and a green LED connected in series, and draws power from the output of the LDO. The lighting of the red LED and the green LED is controlled by the primary-side MCU.

[0010] Furthermore, the temperature sampling circuit is realized by connecting R3 and NTC in series.

[0011] Furthermore, it also includes: an input voltage sampling circuit, which is implemented by voltage division by two resistors R4 and R5, and the input power supply voltage of the inverter is obtained by using the input voltage sampling circuit.

[0012] Furthermore, it also includes: leakage sampling, using the leakage sampling to collect leakage information of the output load and provide it to the AD port of the primary side MCU.

[0013] Furthermore, it also includes: a secondary side MCU, which uses the isolated communication circuit to enable serial communication between the primary side MCU and the secondary side MCU, so that the primary side MCU obtains load abnormality information when the output load is overloaded or short-circuited, and the model of the secondary side MCU is S9KEAZN8AVTG.

[0014] Compared with the prior art, the utility model has the following beneficial effects:

[0015] The utility model adds a real-time indication function of product faults through software programming of the primary-side MCU without changing the original hardware circuit, and modulates various protection status information of the product on the red LED indicator. After the primary-side MCU is powered on and initialized, it will detect the input voltage value, overload, short circuit and leakage of the output load, overtemperature and other information in real time. When relevant abnormal information is detected, the relevant abnormal information is modulated on the red LED indicator control signal in the form of PWM duty cycle, and then the red LED indicator of the socket is controlled and lit, so as to realize the real-time fault analysis function of the product without affecting the original function of the red LED indicator of the power socket. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a circuit flow chart of the LED indicator light of the socket of the utility model.

[0017] In the figure: 1. LDO; 2. Socket LED indicator circuit; 3. Temperature sampling circuit; 4. Primary side MCU; 5. Input voltage sampling circuit; 6. Leakage sampling; 7. Isolation communication circuit; 8. Secondary side MCU. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] The embodiment of the socket LED indicator circuit with real-time fault analysis function is as follows:

[0020] See also Figure 1 A socket LED indicator circuit with real-time fault analysis function includes an LDO1 controlled by an enable pin, a socket LED indicator circuit 2, a temperature sampling circuit 3, a primary side MCU4, an input voltage sampling circuit 5, a leakage sampling 6, an isolation communication circuit 7, and a secondary side MCU8.

[0021] LDO1 provides 5V regulated power supply for primary side MCU4, socket LED indicator circuit 2 and temperature sampling circuit 3; the input of LDO1 is connected to the input power supply, and the output is connected to the VCC pin of MCU, socket LED indicator circuit 2 and temperature sampling circuit 3. Temperature sampling circuit 3 is realized by R3 and NTC in series.

[0022] The red and green LED indicators in the socket LED indicator circuit 2 are installed in a 220V power socket. The socket LED indicator circuit 2 consists of R1 and the red LED in series and R2 and the green LED in series. It draws power from the output of LDO1. The lighting of the red and green LEDs is controlled by the primary-side MCU4 to indicate the working status of the inverter in real time.

[0023] The leakage sampling 6 collects the leakage information of the output load and sends it to the AD port of the primary side MCU4. The isolated communication circuit 7 realizes serial communication between the primary side MCU4 and the secondary side MCU8, so that the primary side MCU4 can obtain the load abnormality information when the output load is overloaded or short-circuited. The model of the secondary side MCU8 is S9KEAZN8AVTG.

[0024] The model of the primary side MCU4 is S9KEAZN8AVTG. The primary side MCU4 can detect and obtain the input power supply voltage, temperature, overload, short circuit and leakage information of the inverter in real time through the built-in AD sampling port and the isolated communication circuit 7, and control the display of the 220V socket LED indicator. When the inverter works normally and outputs 220V voltage, the green indicator light is continuously lit. When the inverter enters the protection state (input undervoltage / overvoltage, output overload / short circuit / leakage, overtemperature), the red light is continuously lit.

[0025] Working principle of socket LED indicator circuit:

[0026] When the primary-side MCU4 detects that the input and output ports of the inverter product enter the relevant protection state due to some abnormal information, it outputs the relevant PWM duty cycle control signal of 120Hz frequency to light up the red LED indicator of the 220V power socket. For example: set the 120Hz frequency PWM signal with a duty cycle of 95% for output short circuit protection, the 120Hz frequency PWM signal with a duty cycle of 90% for output leakage protection, the 120Hz frequency PWM signal with a duty cycle of 85% for output overload protection, the 120Hz frequency PWM signal with a duty cycle of 80% for over-temperature protection, the 120Hz frequency PWM signal with a duty cycle of 75% for input overvoltage protection, and the 120Hz frequency PWM signal with a duty cycle of 70% for input undervoltage protection.

[0027] It is even possible to program and control the abnormal conditions of each circuit module inside the product, for example: the fault of the isolated communication circuit 7 is indicated by a 120Hz frequency PWM signal with a 65% duty cycle, the abnormal voltage of the auxiliary power supply circuit is indicated by a 120Hz frequency PWM signal with a 60% duty cycle, the front-stage cycle-by-cycle overcurrent protection is indicated by a 120Hz frequency PWM signal with a 55% duty cycle, and the rear-stage cycle-by-cycle overcurrent protection is indicated by a 120Hz frequency PWM signal with a 50% duty cycle, etc.

[0028] When the inverter product enters a certain protection state, the engineer uses an external oscilloscope to capture the hard-wired signal of the red LED indicator light in the 220V power socket wiring harness and reads the duty cycle value of its PWM signal. This allows the engineer to quickly learn about the product's fault status and lock the relevant circuits, greatly facilitating further troubleshooting and problem solving.

[0029] In summary, through the implementation of the above technical solutions, real-time analysis of product failures can be achieved without adding new hardware circuits and increasing costs, which greatly facilitates engineers to further troubleshoot, lock in and solve product problems, and can effectively improve the product development progress and the efficiency of after-sales problem analysis, thereby quickly improving the product design quality.

[0030] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A socket LED indicator circuit with real-time fault analysis function, characterized in that: It includes an LDO (1) with an enable pin control, a socket LED indicator circuit (2), a temperature sampling circuit (3), a primary side MCU (4), and an isolated communication circuit (7); The LDO (1) provides a stable voltage supply for the primary-side MCU (4), the socket LED indicator circuit (2) and the temperature sampling circuit (3); the red and green LED indicators in the socket LED indicator circuit (2) are installed in the power socket to indicate the working status of the inverter in real time; The primary-side MCU (4) detects and obtains the input power supply voltage, temperature, overload, short circuit and leakage information of the inverter in real time through its own AD sampling port and isolated communication circuit (7), and controls the red and green light display of the socket LED indicator.

2. The socket LED indicator circuit with real-time fault analysis function according to claim 1, characterized in that: The input of the LDO (1) is connected to the input power supply, and the output is connected to the VCC pin of the primary side MCU (4), the socket LED indicator circuit (2) and the temperature sampling circuit (3).

3. The socket LED indicator circuit with real-time fault analysis function according to claim 2, characterized in that: The socket LED indicator light circuit (2) is composed of R1 and a red LED connected in series, and R2 and a green LED connected in series, and draws power from the output of the LDO (1). The lighting of the red LED and the green LED is controlled by the primary side MCU (4).

4. The socket LED indicator circuit with real-time fault analysis function according to claim 2, characterized in that: The temperature sampling circuit (3) is realized by connecting R3 and NTC in series.

5. The socket LED indicator circuit with real-time fault analysis function according to claim 1, characterized in that: It also includes: an input voltage sampling circuit (5), wherein the input voltage sampling circuit (5) is implemented by voltage division through two resistors R4 and R5, and the input power supply voltage of the inverter is obtained by using the input voltage sampling circuit (5).

6. The socket LED indicator circuit with real-time fault analysis function according to claim 1, characterized in that: Also includes: Leakage sampling (6), using the leakage sampling (6) to collect leakage information of the output load and provide it to the AD port of the primary side MCU (4).

7. The socket LED indicator circuit with real-time fault analysis function according to claim 1, characterized in that: Also includes: The secondary side MCU (8) uses the isolated communication circuit (7) to enable serial communication between the primary side MCU (4) and the secondary side MCU (8), so that the primary side MCU (4) can obtain load abnormality information when an output load is overloaded or short-circuited.

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