Real-time clock built-in battery loss test circuit and electronic equipment

Abstract

The utility model discloses a real-time clock built-in battery loss test circuit and an electronic device, the test circuit comprises a clock circuit and a built-in power supply circuit connected with the clock circuit, the built-in power supply circuit continuously supplies power to the clock circuit, and the test circuit also comprises an MCU micro-control unit, an external power supply circuit and an ADC acquisition module, wherein the MCU micro-control unit comprises an IO port and an ADC port, the external power supply circuit is used for detecting whether an electric leakage fault occurs in the internal power supply circuit and supplying power to the clock circuit, and the ADC acquisition module is used for sampling a clock in real time. The real-time clock circuit can detect whether the built-in power supply circuit has an electric leakage fault in real time and give an alarm in time, meanwhile, a plurality of standby power supply elements can avoid a storage fault caused by power failure, and the reliability of the real-time clock circuit is further improved.

Description

Technical Field

[0001] The utility model relates to the field of real-time clock detection circuits, in particular to a real-time clock built-in battery loss test circuit and electronic equipment. Background Art

[0002] A real-time clock (RTC) circuit typically includes a main power supply, a backup power supply, and a clock chip. Because the built-in power supply is inconvenient to replace, an external power supply is preferred for powering the clock chip when external power is supplied. When no external power is supplied, the clock is powered by an internal battery to maintain operation. For example, the utility model patent with authorization publication number CN201262720Y provides a real-time clock circuit comprising a clock chip, a first diode, a second diode, and a first farad capacitor. This real-time clock circuit has high accuracy. When an external main power supply (VCC) experiences an abnormality, the first farad capacitor is used as a backup battery and isolated by a diode. This ensures that when the external main power supply (VCC) is fault-free, external power is preferred, while battery power is used when the external main power supply (VCC) fails. However, no detection and alarm device or method for detecting internal battery failure is provided. Therefore, the rate of battery depletion in the real-time clock cannot be detected during the normal aging process of the product. In actual production, due to aging time constraints, the real-time clock battery depletes too quickly, and the problem cannot be detected until the customer installs the device or the entire device is sold, and the internal battery is insufficient, resulting in the inability to store the time after power failure. Utility Model Content

[0003] Therefore, in order to solve the above problems, the utility model provides a real-time clock built-in battery loss test circuit and electronic equipment.

[0004] The utility model is realized through the following technical solutions:

[0005] A real-time clock built-in battery loss test circuit includes a clock circuit and a built-in power supply circuit connected to the clock circuit, the built-in power supply circuit continuously supplies power to the clock circuit, and also includes an MCU microcontroller unit, an external power supply circuit, and an ADC acquisition module, wherein:

[0006] The MCU microcontroller unit includes an IO port for connecting to the external power supply circuit and providing a high level or a low level to the external power supply circuit, and the ADC port for connecting to the ADC acquisition module;

[0007] an external power supply circuit, connected to the MCU microcontroller unit via an IO port and connected in parallel with the clock circuit; when receiving a low-level signal from the IO port, the external power supply circuit is disconnected from the clock circuit, allowing the built-in power supply circuit to supply power to the clock circuit alone to detect whether the built-in power supply circuit has a leakage fault; and when receiving a high-level signal from the IO port, the external power supply circuit is connected to the clock circuit and supplies power to the clock circuit;

[0008] The ADC acquisition module is used to sample the clock in real time. It is connected to the MCU micro control unit through the ADC port and is connected in parallel with the clock circuit.

[0009] Preferably, the external power supply circuit includes a transistor Q1, a MOS transistor Q2 and a power supply voltage VCC, the base of the transistor Q1 is connected to the output end of the IO port, the MOS transistor Q2 is connected to the collector of the transistor Q1, the output end of the power supply voltage VCC is connected to the MOS transistor Q2 and the transistor Q1 respectively, and the emitter of the transistor Q1 is grounded.

[0010] Preferably, a capacitor C1 is further provided between the power supply voltage VCC and the MOS transistor Q2, the capacitor C1 and the MOS transistor Q2 are connected in parallel, a resistor R3 is connected between the power supply voltage VCC and the transistor Q1, and a resistor R2 is connected between the MOS transistor Q2 and the transistor Q1.

[0011] Preferably, a resistor R4 is provided between the IO port and the transistor Q1 , a resistor R5 is further provided between the resistor R4 and the transistor Q1 , and the resistor R5 is connected in parallel with the transistor Q1 .

[0012] Preferably, the clock circuit includes a clock chip, an integrated chip U2 and a capacitor C2. The integrated chip U2 is connected to the clock chip. One end of the capacitor C2 is connected to the integrated chip U2, and the other end is grounded.

[0013] Preferably, the built-in power supply circuit includes a battery B1, one end of the battery B1 is grounded, and the other end is connected to the clock circuit through a diode D1, and the external power supply module is connected to the clock module through a diode D2.

[0014] Preferably, it further comprises a resistor R1 connected in parallel with the clock circuit, the ADC acquisition module, the built-in power supply circuit and the external power supply circuit respectively, and one end of the R1 is grounded.

[0015] An electronic device comprises any one of the above-mentioned real-time clock built-in battery loss test circuits.

[0016] The beneficial effects of the technical solution of this utility model are mainly reflected in:

[0017] 1. Set up a built-in power supply circuit and an external power supply circuit respectively, and output a low / high level to the external power supply circuit through the IO port of the MCU microcontroller unit, thereby controlling whether the external power supply circuit supplies power to the clock circuit. On the one hand, when the external power supply circuit is disconnected, the built-in power supply circuit supplies power to the clock circuit alone to detect whether the built-in power supply circuit has a leakage fault; on the other hand, when the built-in power supply circuit fails, the external power supply circuit is connected to the clock circuit to avoid storage failure due to power failure.

[0018] 2. The external power supply circuit includes a supply voltage VCC and a capacitor C1 serving as a backup power source for the supply voltage VCC. When the supply voltage VCC fails, the capacitor C1 can replace the supply voltage VCC and continue to provide power when both the supply voltage VCC and the built-in power circuit are powered off, further improving the reliability of the real-time clock circuit.

[0019] 3. The ADC acquisition module monitors the power supply status of the two power supplies to the clock circuit in real time. When the external power circuit is disconnected and the voltage drop of the built-in power circuit is greater than the set threshold, it can be determined that the product has a built-in battery leakage and an alarm will be issued in time, which can promptly indicate the built-in battery failure and avoid ignoring the situation of rapid loss of the real-time clock battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the circuit structure for testing the battery loss inside the real-time clock;

[0021] Figure 2 This is a functional module diagram of a real-time clock built-in battery loss test circuit. DETAILED DESCRIPTION

[0022] To more clearly and in detail illustrate the objectives, advantages, and features of the present invention, the following non-limiting description of preferred embodiments is provided for illustration and explanation. This embodiment is merely a typical example of the application of the present invention's technical solution. Any technical solution formed by equivalent substitution or equivalent transformation falls within the scope of protection claimed by the present invention.

[0023] At the same time, it is stated that in the description of the scheme, it should be noted that the terms used to indicate the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of description and simplification of description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0024] Furthermore, the terms "first" and "second" in this solution are used for descriptive purposes only and should not be construed as indicating or implying a ranking of importance or implicitly specifying the number of technical features shown. Therefore, features specified as "first" or "second" may explicitly or implicitly include one or more of such features. In this utility model, "plurality" means two or more, unless otherwise specifically defined.

[0025] The utility model discloses a real-time clock built-in battery loss test circuit, such as Figure 1 、 Figure 2 As shown, it includes a clock circuit 2 and a built-in power supply circuit 5 connected to the clock circuit 2, and the built-in power supply circuit 5 continuously supplies power to the clock circuit 2. It also includes an MCU micro control unit 1, an external power supply circuit 4 and an ADC acquisition module 3.

[0026] The MCU microcontroller unit 1 includes an IO port for connecting to the external power supply circuit 4 and providing a high level or a low level to the external power supply circuit 4, and the ADC port for connecting to the ADC acquisition module 3, thereby ensuring whether the external power supply circuit 4 controls power to the clock circuit 2 and ensuring storage and processing of data collected by the ADC acquisition module 3.

[0027] The external power supply circuit 4 is connected to the MCU microcontroller unit 1 via an IO port and is connected in parallel with the clock circuit 2. When the external power supply circuit 4 receives a low-level signal from the IO port, it disconnects from the clock circuit 2, allowing the internal power supply circuit 5 to supply power to the clock circuit 2 alone to detect whether the internal power supply circuit 5 has a leakage fault. When the external power supply circuit 4 receives a high-level signal from the IO port, it connects to the clock circuit 2 and supplies power to the clock circuit 2 to keep the real-time clock running, thereby preventing power-off storage failures caused by a fault in the internal power supply circuit 5.

[0028] like Figure 1As shown, in some embodiments, the external power supply circuit 4 includes a transistor Q1, a MOS transistor Q2, and a power supply voltage VCC. The transistor Q1 is an NPN transistor, wherein the base of the transistor Q1 is connected to the output end of the IO port, and the MOS transistor Q2 is connected to the collector of the transistor Q1, thereby ensuring that the transistor Q1 outputs the amplified current to the MOS transistor Q2. The output end of the power supply voltage VCC is connected to the MOS transistor Q2 and the transistor Q1, respectively, and the emitter of the transistor Q1 is grounded. In actual application, the MCU microcontroller unit 1 controls the transistor Q1 to turn on or off through the IO port. When the transistor Q1 is turned on, the MOS transistor Q2 is also turned on, and the power supply voltage VCC supplies power to the clock circuit 2 through the MOS transistor Q2. When the transistor Q1 is turned off, the MOS transistor Q2 is also turned off, and the power supply voltage VCC cannot supply power to the clock circuit 2. At this time, the built-in power supply circuit 5 supplies power to the clock circuit 2.

[0029] In some embodiments, a capacitor C1 is further provided between the power supply voltage VCC and the MOS transistor Q2. The capacitor C1 serves as a backup battery for the power supply voltage VCC. When the power supply voltage VCC supplies power to the clock circuit 2, the capacitor C1 is simultaneously charged. When the power supply voltage VCC fails, the capacitor C1 can replace it to supply power to the clock circuit 2. The capacitor C1 is connected in parallel with the MOS transistor Q2. A resistor R3 is connected between the power supply voltage VCC and the transistor Q1. A resistor R2 is connected between the MOS transistor Q2 and the transistor Q1. In one embodiment, a resistor R4 is provided between the IO port and the transistor Q1. A resistor R5 is further provided between the resistor R4 and the transistor Q1. The resistor R5 is connected in parallel with the transistor Q1.

[0030] The ADC acquisition module 3 is used to sample the clock circuit 2 in real time. It is connected to the MCU microcontroller unit 1 via an ADC port and is connected in parallel with the clock circuit 2. When the product enters the aging stage, the aging program controls the IO port of the MCU microcontroller unit 1 to shut down the external power supply circuit 4. At this time, the internal power supply circuit 5 continues to supply power to the clock circuit 2. At the same time, the ADC sampler periodically samples the output power of the internal power supply circuit 5. If the voltage drop of the internal power supply circuit 5 exceeds a set threshold during the aging process, the product is determined to have an internal battery leakage. The product will indicate this through a display and an audible alarm. The set threshold can be determined based on the aging environment and aging duration. In one embodiment, the set threshold is 0.3V.

[0031] In one embodiment, the clock circuit 2 includes a clock chip 201, an integrated chip U2 and a capacitor C2. Two pins of the integrated chip U2 are respectively connected to the clock chip 201, and one end of the capacitor C2 is connected to the integrated chip U2 and the other end is grounded.

[0032] In some embodiments, the built-in power supply circuit 5 includes a battery B1, one end of the battery B1 is grounded, and the other end is connected to the clock circuit 2 through a diode D1. The external power supply module is connected to the clock module through a diode D2. In one embodiment, a voltage competition method can be used to make the voltage of the external power supply circuit 4 after passing through the diode D2 higher than the voltage of the built-in power supply circuit 5 after passing through the diode D1, thereby ensuring that when the external power supply circuit 4 and the built-in power supply circuit 5 are both turned on, the voltage of the external battery is used first.

[0033] In some embodiments, a resistor R1 is further included which is connected in parallel with the clock circuit 2 , the ADC acquisition module 3 , the built-in power supply circuit 5 and the external power supply circuit 4 , respectively. One end of the resistor R1 is grounded, thereby reducing the total resistance.

[0034] The utility model also provides an electronic device, comprising any one of the above-mentioned real-time clock built-in battery loss test circuits.

[0035] There are many implementation methods for the present utility model, and all technical solutions formed by equivalent transformation or equivalent transformation fall within the protection scope of the present utility model.

Claims

1. A real-time clock built-in battery loss test circuit, comprising a clock circuit and a built-in power supply circuit connected to the clock circuit, wherein the built-in power supply circuit continuously supplies power to the clock circuit, characterized in that: It also includes an MCU microcontroller unit, an external power supply circuit, and an ADC acquisition module, among which: The MCU microcontroller unit includes an IO port for connecting to the external power supply circuit and providing a high level or a low level to the external power supply circuit, and an ADC port for connecting to the ADC acquisition module; an external power supply circuit, connected to the MCU microcontroller unit via an IO port and connected in parallel with the clock circuit; when receiving a low-level signal from the IO port, the external power supply circuit is disconnected from the clock circuit, allowing the built-in power supply circuit to supply power to the clock circuit alone to detect whether the built-in power supply circuit has a leakage fault; and when receiving a high-level signal from the IO port, the external power supply circuit is connected to the clock circuit and supplies power to the clock circuit; The ADC acquisition module is used to sample the clock in real time. It is connected to the MCU micro control unit through the ADC port and is connected in parallel with the clock circuit.

2. The real-time clock built-in battery loss test circuit according to claim 1, characterized in that: The external power supply circuit includes a transistor Q1, a MOS transistor Q2, and a power supply voltage VCC. The base of the transistor Q1 is connected to the output end of the IO port, the MOS transistor Q2 is connected to the collector of the transistor Q1, the output end of the power supply voltage VCC is connected to the MOS transistor Q2 and the transistor Q1 respectively, and the emitter of the transistor Q1 is grounded.

3. The real-time clock built-in battery loss test circuit according to claim 2, characterized in that: A capacitor C1 is further provided between the power supply voltage VCC and the MOS transistor Q2. The capacitor C1 and the MOS transistor Q2 are connected in parallel. A resistor R3 is connected between the power supply voltage VCC and the transistor Q1. A resistor R2 is connected between the MOS transistor Q2 and the transistor Q1.

4. The real-time clock built-in battery loss test circuit according to claim 3, characterized in that: A resistor R4 is provided between the IO port and the transistor Q1 , and a resistor R5 is further provided between the resistor R4 and the transistor Q1 . The resistor R5 is connected in parallel with the transistor Q1 .

5. The real-time clock built-in battery loss test circuit according to claim 1, characterized in that: The clock circuit includes a clock chip, an integrated chip U2 and a capacitor C2. The integrated chip U2 is connected to the clock chip. One end of the capacitor C2 is connected to the integrated chip U2, and the other end is grounded.

6. The real-time clock built-in battery loss test circuit according to claim 1, characterized in that: The built-in power supply circuit includes a battery B1, one end of the battery B1 is grounded, and the other end is connected to the clock circuit through a diode D1, and the external power supply module is connected to the clock module through a diode D2.

7. The real-time clock built-in battery loss test circuit according to claim 1, characterized in that: It also includes a resistor R1 connected in parallel with the clock circuit, the ADC acquisition module, the built-in power supply circuit and the external power supply circuit respectively, and one end of the R1 is grounded.

8. Electronic equipment, characterized in that: The invention comprises a real-time clock built-in battery loss test circuit as described in any one of claims 1-7.

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