A maintenance-free power failure detection circuit for home electronic devices

Abstract

This utility model discloses a maintenance-free power-off detection circuit for household electronic devices, including a main control circuit, a power supply circuit, a detection circuit, and a discharge circuit. The main control circuit includes a controller U1; the power supply circuit includes a power input terminal VIN and a power input terminal VBAT; the detection circuit includes a first voltage acquisition circuit and a second voltage acquisition circuit; and the discharge circuit includes a field-effect transistor Q1. This maintenance-free power-off detection circuit for household electronic devices utilizes the linkage of the main control circuit, power supply circuit, detection circuit, and discharge circuit to complete the detection of component loss in the electronic device.

Description

Technical Field

[0001] This utility model belongs to the field of power failure detection technology, specifically relating to a power failure detection circuit for maintenance-free household electronic devices. Background Technology

[0002] With the increasing aging population, smart devices are often used to detect abnormal behavior in the elderly in real time, such as falls or prolonged stays, and to monitor the elderly's safety at night, such as sleep monitors. The main target group of these products is elderly people living alone. This group does not have any device maintenance capabilities. When the device goes offline, the back-end device maintenance personnel have to go to the site to troubleshoot if they cannot determine the cause of the offline situation, resulting in particularly high maintenance costs. In actual application scenarios, most device offline situations are caused by power loss, especially when the elderly actively disconnect the device from the power supply. In fact, such problems can be solved by family members remotely asking the elderly to power on the device themselves, avoiding the additional costs incurred by device maintenance personnel going to the site.

[0003] Therefore, further improvements will be made to address the aforementioned issues. Utility Model Content

[0004] The main purpose of this utility model is to provide a maintenance-free power failure detection circuit for home electronic devices, which uses a main control circuit, a power supply circuit, a detection circuit and a discharge circuit to work together to detect the loss of components in the electronic device.

[0005] To achieve the above objectives, this utility model provides a maintenance-free power-off detection circuit for household electronic devices, including a main control circuit, a power supply circuit, a detection circuit, and a discharge circuit, wherein:

[0006] The main control circuit includes a controller U1;

[0007] The power supply circuit includes a power input terminal VIN and a power input terminal VBAT. The power input terminal VIN (connected to AC power via a power adapter) is connected to the power output terminal (VDD_BRD) via diode D12. The power input terminal VBAT is connected to the positive terminal of battery BT1, and the positive terminal of battery BT1 is also connected to the power output terminal (VDD_BRD) via diode D13.

[0008] The detection circuit includes a first voltage acquisition circuit and a second voltage acquisition circuit, wherein:

[0009] The first voltage acquisition circuit includes a resistor R8 and a resistor R14 connected in series. The end of the resistor R8 away from the resistor R14 is connected to the power input terminal VBAT, and the end of the resistor R14 away from the resistor R8 is grounded. The common terminal (ADC1_CH0) of the resistor R8 and the resistor R14 is electrically connected to the first acquisition terminal (4 pins) of the controller U1.

[0010] The second voltage acquisition circuit includes resistors R9 and R15 connected in series. The end of resistor R9 away from resistor R15 is connected to the power input terminal VIN, and the end of resistor R15 away from resistor R9 is grounded. The common terminal (ADC1_CH1) of resistors R9 and R15 is electrically connected to the second acquisition terminal (pin 5) of the controller U1.

[0011] The discharge circuit includes a field-effect transistor Q1. The gate of the field-effect transistor Q1 is electrically connected to the control terminal (pin 14) of the controller U1 through a resistor R6. The drain of the field-effect transistor Q1 is connected to the power input terminal VBAT through a resistor R2, and the source of the field-effect transistor Q1 is grounded.

[0012] As a further preferred embodiment of the above technical solution, a resistor R53 is connected between the power input terminal VIN and the power input terminal VBAT, and the power output terminal is also grounded through a filter capacitor C61 and a filter capacitor C62, respectively.

[0013] As a further preferred embodiment of the above technical solution, the common terminal of resistor R8 and resistor R14 is also grounded through capacitor C4, and the common terminal of resistor R9 and resistor R15 is also grounded through capacitor C5.

[0014] As a further preferred embodiment of the above technical solution, a resistor R7 is connected between the gate and source of the field-effect transistor Q1.

[0015] As a further preferred technical solution of the above technical solution, resistors R2, R3, R4 and R5 are connected in parallel across the two ends of resistor R2, respectively. Attached Figure Description

[0016] Figure 1 This is the power supply circuit diagram of this utility model.

[0017] Figure 2 This is the detection circuit diagram of this utility model.

[0018] Figure 3 This is the discharge circuit diagram of this utility model.

[0019] Figure 4This is the main control circuit diagram of this utility model. Detailed Implementation

[0020] The following description is intended to disclose the present invention so that those skilled in the art can implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art. The basic principles of the present invention defined in the following description can be applied to other embodiments, modifications, improvements, equivalents, and other technical solutions that do not depart from the spirit and scope of the present invention.

[0021] This utility model discloses a power failure detection circuit for maintenance-free household electronic devices. The specific embodiments of the utility model are further described below with reference to preferred embodiments.

[0022] In the embodiments of this utility model, those skilled in the art will note that the electronic devices and the like involved in this utility model can be considered as prior art.

[0023] Preferred embodiment.

[0024] like Figure 1-4 As shown, this utility model discloses a power-off detection circuit for maintenance-free household electronic devices, including a main control circuit, a power supply circuit, a detection circuit, and a discharge circuit, wherein:

[0025] The main control circuit includes a controller U1;

[0026] The power supply circuit includes a power input terminal VIN and a power input terminal VBAT. The power input terminal VIN (connected to AC power via a power adapter) is connected to the power output terminal (VDD_BRD) via diode D12. The power input terminal VBAT is connected to the positive terminal of battery BT1, and the positive terminal of battery BT1 is also connected to the power output terminal (VDD_BRD) via diode D13.

[0027] The detection circuit includes a first voltage acquisition circuit and a second voltage acquisition circuit, wherein:

[0028] The first voltage acquisition circuit includes a resistor R8 and a resistor R14 connected in series. The end of the resistor R8 away from the resistor R14 is connected to the power input terminal VBAT, and the end of the resistor R14 away from the resistor R8 is grounded. The common terminal (ADC1_CH0) of the resistor R8 and the resistor R14 is electrically connected to the first acquisition terminal (4 pins) of the controller U1.

[0029] The second voltage acquisition circuit includes resistors R9 and R15 connected in series. The end of resistor R9 away from resistor R15 is connected to the power input terminal VIN, and the end of resistor R15 away from resistor R9 is grounded. The common terminal (ADC1_CH1) of resistors R9 and R15 is electrically connected to the second acquisition terminal (pin 5) of the controller U1.

[0030] The discharge circuit includes a field-effect transistor Q1. The gate of the field-effect transistor Q1 is electrically connected to the control terminal (pin 14) of the controller U1 through a resistor R6. The drain of the field-effect transistor Q1 is connected to the power input terminal VBAT through a resistor R2, and the source of the field-effect transistor Q1 is grounded.

[0031] Specifically, a resistor R53 is connected between the power input terminal VIN and the power input terminal VBAT, and the power output terminal is also grounded through a filter capacitor C61 and a filter capacitor C62, respectively.

[0032] More specifically, the common terminal of resistors R8 and R14 is also grounded through capacitor C4, and the common terminal of resistors R9 and R15 is also grounded through capacitor C5.

[0033] Furthermore, a resistor R7 is connected between the gate and source of the field-effect transistor Q1.

[0034] Furthermore, resistors R2, R3, R4, and R5 are connected in parallel across the two ends of resistor R2, respectively.

[0035] Regarding this utility model:

[0036] To achieve power-off detection in electronic products, two key functions must be implemented:

[0037] 1. Electronic devices need to implement relevant detection circuits to detect when power is cut off;

[0038] 2. After detecting that the power supply to the electronic device has been disconnected, the backend must ensure that it can receive the power failure message for a certain period of time after the power failure. The device must still have the necessary data transmission capability for a certain period of time after the power failure.

[0039] like Figure 1 As shown, the design has two power supplies. One is AC power, which is converted into DC5V or DC12V DC power commonly used by the equipment after passing through a power adapter. When the equipment is not powered off, the power supply is VIN.

[0040] The other path is a backup power supply, with VBAT as the input source. Generally, VIN is larger than VBAT. A low-dropout diode is connected in series between the two inputs to isolate the two power supplies.

[0041] Figure 2 For the actual testing circuit, the device continuously collects the voltage values ​​of ADC1_CH0 and ADC1_CH1 at regular intervals. The timer interval determines the detection response speed. When the main control processor U1 has sufficient performance, the timer interval should be no less than 5ms. Under normal power supply conditions, ADC1_CH1 is greater than ADC1_CH0. When the VIN voltage drops to 0 (the device is powered off), the device's power supply is immediately provided by the backup power supply VBAT. At this time, ADC1_CH1 is less than ADC1_CH0. Once this condition is detected, an event push message is immediately triggered to notify the remote maintenance platform that a power outage event has occurred. The device's response time to this event determines the power output that the backup power supply needs to support.

[0042] Figure 3 A necessary discharge circuit is included to ensure that excess power is quickly released after power-off detection, preventing the system from being in an unstable state under low voltage conditions. The shorter this unstable state, the better. The discharge function is implemented by controlling GPIO26 to a high level. When GPIO26 is high, pins 2 and 3 of the MOSFET Q1 are turned on, and VBAT establishes a fast discharge circuit.

[0043] The beneficial effects of this utility model are as follows:

[0044] This circuit is inexpensive and consumes very few software resources, allowing for rapid portability to related products. Applying this circuit significantly reduces maintenance costs for customers, increases user satisfaction with product quality, and reduces misconnections due to product issues (previously, offline devices were often mistakenly attributed to malfunction).

[0045] It is worth mentioning that the technical features of electronic devices and other related technologies involved in this utility model patent application should be regarded as prior art. The specific structure, working principle, and possible control methods and spatial arrangement of these technical features can be adopted using conventional choices in the field and should not be regarded as the inventive point of this utility model patent. This utility model patent will not elaborate further.

[0046] For those skilled in the art, modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A maintenance-free power-off detection circuit for household electronic devices, characterized in that, It includes a main control circuit, a power supply circuit, a detection circuit, and a discharge circuit, among which: The main control circuit includes a controller U1; The power supply circuit includes a power input terminal VIN and a power input terminal VBAT. The power input terminal VIN is connected to the power output terminal through a diode D12. The power input terminal VBAT is connected to the positive terminal of battery BT1, and the positive terminal of battery BT1 is also connected to the power output terminal through a diode D13. The detection circuit includes a first voltage acquisition circuit and a second voltage acquisition circuit, wherein: The first voltage acquisition circuit includes a resistor R8 and a resistor R14 connected in series. The end of the resistor R8 away from the resistor R14 is connected to the power input terminal VBAT, and the end of the resistor R14 away from the resistor R8 is grounded. The common terminal of the resistor R8 and the resistor R14 is electrically connected to the first acquisition terminal of the controller U1. The second voltage acquisition circuit includes a resistor R9 and a resistor R15 connected in series. The end of the resistor R9 away from the resistor R15 is connected to the power input terminal VIN, and the end of the resistor R15 away from the resistor R9 is grounded. The common terminal of the resistors R9 and R15 is electrically connected to the second acquisition terminal of the controller U1. The discharge circuit includes a field-effect transistor Q1. The gate of the field-effect transistor Q1 is electrically connected to the control terminal of the controller U1 through a resistor R6. The drain of the field-effect transistor Q1 is connected to the power input terminal VBAT through a resistor R2, and the source of the field-effect transistor Q1 is grounded.

2. The power failure detection circuit for maintenance-free household electronic devices according to claim 1, characterized in that, A resistor R53 is connected between the power input terminal VIN and the power input terminal VBAT. The power output terminal is also grounded through filter capacitor C61 and filter capacitor C62, respectively.

3. The power-off detection circuit for maintenance-free household electronic devices according to claim 2, characterized in that, The common terminal of resistors R8 and R14 is also grounded through capacitor C4, and the common terminal of resistors R9 and R15 is also grounded through capacitor C5.

4. The power-off detection circuit for maintenance-free household electronic devices according to claim 3, characterized in that, A resistor R7 is connected between the gate and source of the field-effect transistor Q1.

5. The power-off detection circuit for maintenance-free household electronic devices according to claim 4, characterized in that, The two ends of the resistor R2 are respectively connected to resistor R2, resistor R3, resistor R4 and resistor R5.

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