Voltage detection circuit and electronic equipment

Abstract

The embodiment of the utility model provides a voltage detection circuit and an electronic device, and the voltage detection circuit comprises a controller which is used for providing an enable signal, and the enable signal is used for controlling the connection or disconnection of a first switching tube; the switching circuit comprises a first switching tube and a second switching tube, the first end of the first switching tube is connected with the controller, the second end of the first switching tube is connected with the first end of the second switching tube, the second end of the second switching tube is connected with the controller, the third end of the second switching tube is connected with the output node, and the output node is connected with the controller. And when the first switch tube is switched off, the second switch tube is switched on, so that the controller can detect the voltage of the output node.

Description

Technical Field

[0001] Embodiments of the present utility model relate to the field of electronic devices, and particularly to a voltage detection circuit and an electronic device. Background Art

[0002] Generally, an RTC (Real Time Clock) battery is installed on a server motherboard. The RTC battery can be used to supply power to a volatile memory chip to maintain the settings of the basic input / output interface, or to supply power to other circuit modules. The existing monitoring of the RTC battery only limits to monitoring the output current of the current RTC battery, and cannot monitor the life condition of the RTC battery. Furthermore, it is impossible to judge the time when the RTC battery needs to be replaced, and it is impossible to ensure the stable operation of the server motherboard.

[0003] In an electronic device, in order to ensure that system date, time and other information can be continuously calculated in the shutdown state, or to prevent some important data from being cleared with shutdown, an independent battery is generally configured on the motherboard of the electronic device for use by specific functional electronic components, such as a Real-Time Clock Chip (RTC Chip) for calculating the system time and a Complementary Metal Oxide Semiconductor RAM (CMOS RAM) for storing system parameter settings (such as BIOS settings), so as to achieve the function of sustainable operation in the shutdown state. And this type of battery is generally called a Real-Time Clock (RTC) battery.

[0004] Under the detection program of a general electronic device, when a tester finds that the electronic device is operating abnormally, only by disassembling the machine for inspection can it be determined whether the abnormal condition is caused by the RTC battery falling off. And the action of disassembling the machine for inspection will inevitably reduce the efficiency of the detection process and bring an additional workload to the tester. In addition, during the process of disassembling the machine for inspection, other parts of the electronic device may also be damaged due to other human reasons.

[0005] Since the power of the RTC battery is limited and non-rechargeable, according to the requirements of the server and PC system life, a single RTC battery often cannot support the entire life cycle of the server. Therefore, if it is possible to detect whether the RTC battery voltage is depleted, it will be convenient for maintenance and replacement of a new battery. The existing RTC battery voltage detection circuit detects the battery voltage in real time, and this real-time detection method will consume part of the battery power and shorten the battery usage time.

[0006] Therefore, how to automatically detect the voltage of the RTC battery and minimize the waste of the RTC battery power is a problem that those skilled in the art need to solve. Summary of the Invention

[0007] An embodiment of the present invention provides a voltage detection circuit and an electronic device, which can at least automatically detect the voltage of the RTC battery and minimize the waste of the RTC battery power.

[0008] An embodiment of the present invention provides a battery voltage detection circuit for connecting to the output node of the RTC battery, including: a controller for providing an enable signal, where the enable signal is used to control the conduction or disconnection of the first switching tube; the switching circuit includes a first switching tube and a second switching tube, the first end of the first switching tube is connected to the controller, the second end of the first switching tube is connected to the first end of the second switching tube, the second end of the second switching tube is connected to the controller, and the third end of the second switching tube is connected to the output node, and the second switching tube conducts when the first switching tube is disconnected, so that the controller can detect the voltage of the output node.

[0009] In some embodiments, the first switching tube includes a first MOS transistor, the gate of the first MOS transistor is the first end of the first MOS transistor, the first end of the first MOS transistor is connected to the controller, the third end of the first MOS transistor is grounded, and the second end of the first MOS transistor is connected to the second switching tube.

[0010] In some embodiments, the second switching tube includes a second MOS transistor, the gate of the second MOS transistor is connected to the operating power supply, the gate of the second MOS transistor is the first end of the second MOS transistor and is also connected to the second end of the first MOS transistor, the third end of the second MOS transistor is connected to the output node, and the second end of the second MOS transistor is connected to the controller.

[0011] In some embodiments, the second switching tube is disconnected when the first switching tube conducts, so that the output node is disconnected from the controller.

[0012] In some embodiments, the second end of the first MOS transistor is also electrically connected to the operating power supply.

[0013] In some embodiments, both the first MOS transistor and the second MOS transistor are NMOS transistors.

[0014] In some embodiments, both the first MOS transistor and the second MOS transistor are PMOS transistors.

[0015] In some embodiments, the controller further includes an analog-to-digital conversion module for converting the voltage of the output node into a digital signal.

[0016] In some embodiments, the controller further includes: a comparison module configured to compare the current voltage of the received output node with a preset voltage; an alarm module configured to send an alarm prompt message when the comparison signal is abnormal, where the abnormal comparison signal means that the current voltage of the output node of the RTC battery is less than the preset voltage.

[0017] Correspondingly, an embodiment of the present invention further provides an electronic device, including the RTC battery voltage detection circuit according to any one of the above embodiments.

[0018] The technical solution provided by the embodiment of the present invention has the following advantages:

[0019] The RTC automatic detection circuit provided by the embodiment of the present invention can automatically detect the voltage of the RTC battery, and the RTC detection circuit can detect the voltage of the RTC battery, which can reduce a manual inspection station and ensure no missed detection, meet the automation requirements of testing, and greatly save labor and time costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] One or more embodiments are exemplarily illustrated by the pictures in the corresponding drawings. Unless otherwise stated, the figures in the drawings do not constitute a proportional limitation.

[0021] Figure 1 FIG. 1 is a first schematic structural diagram of a voltage detection circuit provided by an embodiment of the present invention;

[0022] Figure 2 FIG. 2 is a circuit diagram of a battery voltage detection circuit provided by an embodiment of the present invention;

[0023] Figure 3 FIG. 3 is another circuit diagram of a battery voltage detection circuit provided by an embodiment of the present invention;

[0024] Figure 4 FIG. 4 is a second schematic structural diagram of a voltage detection circuit provided by an embodiment of the present invention;

[0025] Figure 5 FIG. 5 is a third schematic structural diagram of a voltage detection circuit provided by an embodiment of the present invention;

[0026] Figure 6 FIG. 6 is a schematic structural diagram of an electronic device provided by an embodiment of the present invention;

[0027] Figure 7 FIG. 7 is a flowchart of an RTC battery voltage detection method provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] As is known from the background art, currently, the voltage of the RTC battery cannot be automatically detected and the detection continuously wastes the power of the RTC battery.

[0029] The RTC automatic detection circuit provided by the embodiment of the present utility model can realize the automatic detection of the RTC battery voltage. The RTC detection circuit can detect the RTC battery voltage, reduce one manual inspection station, ensure no missed detection, meet the automation requirements of testing, and greatly save labor and time costs.

[0030] In the description of the embodiments of the present utility model, technical terms such as "first" and "second" are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity, specific order or primary-secondary relationship of the indicated technical features. In the description of the embodiments of the present utility model, the meaning of "a plurality of" is more than two, unless otherwise clearly and specifically defined.

[0031] Referring to "embodiments" herein means that the specific features, structures or characteristics described in connection with the embodiments can be included in at least one embodiment of the present utility model. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0032] In the description of the embodiments of the present utility model, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can mean: there is A, there is both A and B, and there is B. In addition, the character " / " in this article generally represents an "or" relationship between the associated objects before and after.

[0033] In the description of the embodiments of the present utility model, the term "a plurality of" refers to more than two (including two). Similarly, "a plurality of groups" refers to more than two groups (including two groups), and "a plurality of pieces" refers to more than two pieces (including two pieces).

[0034] In the description of the embodiments of the present utility model, the orientation or positional relationship indicated by technical terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of the present utility model and simplifying the description, and does not indicate or imply that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the embodiments of the present utility model.

[0035] In the description of the embodiments of the present utility model, unless otherwise clearly specified and defined, technical terms such as "installation", "connection", "connection", "fixation", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can also be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to specific circumstances.

[0036] In the corresponding drawings of the embodiments of the present application, for better understanding and description, the thickness and area of the layer are enlarged. When describing a component (such as a layer, film, region or substrate) on or on the surface of another component, the component can be "directly" on the surface of the other component, or there can be a third component between the two components. On the contrary, when describing a component on the surface of another component or when another component is formed or provided on the surface of a component, it means that there is no third component between the two components. In addition, when describing a component "substantially" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor on a partial edge of the entire surface.

[0037] In the description of the embodiments of the present utility model, when a certain component "includes" another component, unless otherwise stated, other components are not excluded, and other components may further be included. In addition, when components such as layers, films, regions or plates are referred to as "on / located on" another component, it can be "directly on" the other component (that is, on the surface of the other component and there is no other component between the two), or there can be another component between them. In addition, when components such as layers, films, regions, plates are "directly located on" another component, or when components such as layers, films, regions, plates are located on the surface of another component, it means that there is no other component between them.

[0038] The terms used in the description of the various embodiments herein are only for describing specific embodiments and are not intended to be limiting. As used in the description of the various embodiments and the appended claims, "the part" is also intended to include the plural form, unless the context clearly indicates otherwise. Among them, the components include components such as layers, films, regions or plates.

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the following will elaborate on each embodiment of the present utility model with reference to the accompanying drawings. However, those of ordinary skill in the art can understand that in each embodiment of the present utility model, many technical details are provided to help readers better understand the present utility model. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present utility model can still be implemented.

[0040] Figure 1 The first structural schematic diagram of the battery voltage detection circuit provided by an embodiment of the present utility model; Figure 2 A circuit diagram of the battery voltage detection circuit provided by an embodiment of the present utility model.

[0041] Reference Figure 1 , an embodiment of the present utility model provides a battery voltage detection circuit for connecting to the output node of an RTC battery, including: a controller for providing an enable signal, where the enable signal is used to control the conduction or disconnection of a first switching tube; the switching circuit includes a first switching tube and a second switching tube, the first end of the first switching tube is connected to the controller, the second end of the first switching tube is connected to the first end of the second switching tube, the second end of the second switching tube is connected to the controller, the third end of the second switching tube is connected to the output node, and when the first switching tube is disconnected, the second switching tube is conductive, so that the controller can detect the voltage of the output node.

[0042] In some embodiments, when the enable signal is valid, it indicates that the voltage of the output node needs to be detected, and when the enable signal is invalid, it indicates that the voltage of the output node does not need to be detected; during the valid period of the enable signal, the first switching tube is cut off, and during the invalid period of the enable signal, the first switching tube is conductive;

[0043] In some embodiments, when the first switching tube is conductive, the second switching tube is disconnected, so that the output node is disconnected from the controller.

[0044] In some embodiments, the valid period of the enable signal refers to the period when the voltage of the output node needs to be detected, that is, the first switching tube is in the cut-off state, the second switching tube is in the conductive state, the processor is connected to the output node, and the voltage of the output node is detected; the invalid period of the enable signal refers to the period when the voltage of the output node does not need to be detected, that is, the first switching tube is in the conductive state, the second switching tube is in the cut-off state, the processor is disconnected from the output node, and there is no need to detect the voltage of the output node.

[0045] The RTC battery circuit 100 can be the RTC battery circuit of any electronic device. The present utility model takes Figure 2The RTC battery voltage shown is for example, but this does not constitute a limitation of the present utility model to the RTC battery voltage. As long as the detection circuit of the voltage of the RTC battery circuit that supplies power to the RTC chip in the electronic device and other components that can serve as the RTC chip meets the conditions, it is a qualified RTC battery circuit.

[0046] Reference Figure 2 , the RTC battery circuit 100 is coupled to the electronic component 104, and the electronic component 104 can be the corresponding RTC processing chip in the electronic device. The electronic device can be, for example, a desktop computer, a laptop computer, a tablet computer, a personal digital assistant (PDA), or a smart phone, etc. The electronic component 10 can be, for example, an RTC chip, a CMOS RAM, or other electronic components inside the electronic device, and the present utility model is not limited thereto.

[0047] In some embodiments, the RTC battery circuit 100 may include an auxiliary bias source 101, a Schottky diode 102, and an RTC battery 103. The power output terminal of the RTC battery 103 is coupled to the Schottky diode 102 via an input resistor R1, and then coupled to the electronic component 104 via the Schottky diode 102 to supply power to the electronic component 104 for use. Among them, the electronic component 104 is coupled to the Schottky diode 102 via a capacitor C. The capacitor C is a decoupling capacitor, which is arranged close to the electronic component 104 to filter out high-frequency noise, make the voltage stable and clean, and ensure the normal operation of the component.

[0048] In some embodiments, the capacitor C is arranged close to the RTC chip and is used to bypass the noise coupled on the RTC chip to the ground, leaving only the signal after removing the noise to supply power to the subsequent circuits (including the RTC chip).

[0049] In some embodiments, a decoupling capacitor can be coupled to each load in the circuit components to remove noise and improve the accuracy of each detection signal.

[0050] In some embodiments, the input resistor R1 is a current-limiting resistor, and the current-limiting resistor can reduce the discharge current of the capacitor C, thereby reducing the current loss of the capacitor C during the discharge and charge processes, and further improving the lifespan of the RTC battery itself.

[0051] In some embodiments, the Schottky diode 102 can be, for example, a three-terminal Schottky diode having two anode terminals TDP1, TDP2 and one cathode terminal TDN. Among them, the anode terminal TDP1 is coupled to the auxiliary bias voltage source 101, the anode terminal TDP2 is coupled to the power output terminal of the RTC battery 103, and the cathode terminal TDN is coupled to the electronic component 104.

[0052] In some embodiments, the Schottky diode 102 can be two Schottky diodes (D1 and D2) connected in parallel. The anode terminal of one Schottky diode D1 is coupled to the auxiliary bias voltage source 101, and the cathode terminal TDN is coupled to the electronic component 104. The anode terminal TDP2 of the other Schottky diode D2 is coupled to the power output terminal of the RTC battery 103, and the cathode terminal TDN is coupled to the electronic component 104.

[0053] In some embodiments, a Schottky diode is used as the diode between the electronic component 104 and the RTC battery 103. Based on the low leakage current of the Schottky diode itself, the power consumption speed of the RTC battery 103 can be reduced, thereby increasing the service life of the RTC battery 103.

[0054] In some embodiments, the auxiliary bias voltage source 101 can be an LDO (low dropout regulator) voltage regulator to stably supply power to the Schottky diode 102. The LDO voltage regulator can provide a 3A current, and the maximum voltage drop is only 110 mV. The output voltage of this device can be adjusted by an external resistor divider, and the range is 0.8V to 5.2V. Among them, V3P3 represents the output voltage of 3.3V.

[0055] In some embodiments, the maximum input voltage of the electronic component 104 is 3V.

[0056] In some embodiments, in order to detect the configuration status and voltage status of the RTC battery 103, the detection circuit extracts the power signal VP from the output node A between the RTC battery 103 and the Schottky diode 102. In this way, the forward bias effect of the Schottky diode 102 on the power signal VP can be excluded, so as to accurately detect the voltage of the RTC battery 103 itself, and then it can be known whether the RTC battery 103 is properly configured in the RTC battery circuit 100.

[0057] In some embodiments, the first switching transistor 111 includes a first MOS transistor. The gate G of the first MOS transistor is the first end of the first MOS transistor. The first end of the first MOS transistor is connected to the controller 120 to receive the enable signal. The third end D of the first MOS transistor is grounded, and the second end S of the first MOS transistor is connected to the second switching transistor 112.

[0058] In some embodiments, the second switching transistor 112 includes a second MOS transistor. The gate G of the second MOS transistor is connected to the operating power supply 113. The gate of the second MOS transistor is the first end of the second MOS transistor and is also connected to the second end S of the first MOS transistor. The third end D of the second MOS transistor is connected to the output node A, and the second end S of the second MOS transistor is connected to the controller 120.

[0059] In some embodiments, based on the second MOS transistor, when testing is required, the second MOS transistor can be turned on through the gate G of the second MOS transistor to output a detection result signal, that is, the processor 120 is turned on to communicate with the RTC battery circuit 100 and transmit the detection result signal, so that the processor 120 can determine whether the RTC battery 103 is properly configured in the RTC battery circuit 100 according to the detection result signal. Also, based on the second MOS transistor, when testing is not required, the second MOS transistor can be made to be in an off state through the gate G of the second MOS transistor, that is, a short-circuit state exists between the processor 120 and the RTC battery circuit 100. In this way, the processor 120 detects the power signal only during testing, and when testing is not required, the number of components is reduced, the number of electronic components that consume the RTC battery 103 is reduced, and the number of discharges of the RTC battery 103 is reduced, thereby reducing the rate of power loss of the RTC battery 103 and improving the lifespan of the RTC battery 103.

[0060] In addition, the processor 120 also outputs a power signal VP according to the detection result signal, that is, outputs the voltage signal of the RTC battery 103, so that the tester can more intuitively observe the voltage signal of the RTC battery 103.

[0061] For example, if the collected power signal VP is a high-level voltage signal (such as the voltage of the RTC battery is 3.3V), it means that the RTC battery 103 is in a normal configuration state at this time (that is, the RTC battery 103 is normally connected to other circuit components / conductors and can normally supply power to the electronic component 104). Therefore, the first switching transistor 111 generates an enabled detection result signal according to the power signal VP, enabling the processor to determine that the RTC battery 103 is in a normal configuration state; conversely, if the collected power signal VP is a low-level voltage signal (such as 0V), it means that the RTC battery 103 is in an abnormal configuration state at this time (that is, the RTC battery 103 is detached or the connection between the RTC battery 103 and other circuit components / conductors is abnormal (such as a broken wire or a short circuit in the circuit), resulting in the RTC battery 103 being in an abnormal configuration state.

[0062] In some embodiments, the second terminal S of the first MOS transistor is also electrically connected to the working power supply 131.

[0063] In some embodiments, both the first MOS transistor and the second MOS transistor are NMOS transistors.

[0064] In some embodiments, the voltage-dividing resistor R2 is connected between the working power supply 131 and the gate G of the second MOS transistor. The voltage value of the working power supply 131 can be 5.0V.

[0065] If the RTC battery voltage acquisition command is at a low level, otherwise, it is at a high level. The detection mechanism for the first switching transistor 111 and the second switching transistor 112 of the NMOS transistor is as follows:

[0066] When the RTC battery voltage acquisition command is at a low level (0V), for the first switching transistor 111, the gate G (the first terminal) of the first switching transistor 111 receives the RTC battery voltage acquisition command, that is, when the gate G (the first terminal) of the first switching transistor 111 is at a low level (0V), the second terminal S of the first switching transistor 111 is electrically connected to the working power supply 113, that is, the voltage of the second terminal S of the first switching transistor 111 is 5.0V at this time, the third terminal D of the first switching transistor 111 is connected to the ground, and the voltage is 0V, then VGS is less than the threshold voltage VT2 of the first switching transistor 111, and the first switching transistor 111 is in a non-conducting state at this time. For the second switching transistor 112, since the first switching transistor 111 is in a non-conducting state, the gate G (the first terminal) of the second switching transistor 112 presents the voltage value of the working power supply 113, that is, the gate G (the first terminal) of the second switching transistor 112 is at a high level (5.0V), the third terminal D of the second switching transistor 112 presents the power supply voltage VP (that is, less than or equal to 3.3V), the second terminal S of the second switching transistor 112 presents a low level, then VGS is greater than the threshold voltage VT1 of the second switching transistor 112, and the second switching transistor 112 is in a conducting state, that is, the RTC battery circuit 100 is electrically connected to the processor 120, and the power supply voltage can be collected by the processor 120 via the third terminal D and the second terminal S of the second switching transistor 112.

[0067] When the RTC battery voltage acquisition command is at a high level (3.3V), for the first switching transistor 111, the gate G (the first end) of the first switching transistor 111 receives the RTC battery voltage acquisition command. That is, when the gate G (the first end) of the first switching transistor 111 is at a high level, the second end S of the first switching transistor 111 is electrically connected to the working power supply 113. That is, the voltage of the second end S of the first switching transistor 111 is 5.0V at this time, and the third end D of the first switching transistor 111 is connected to the ground, and the voltage is 0V. Then, VGS is greater than the threshold voltage VT2 of the first switching transistor 111, and the first switching transistor 111 is in a conducting state at this time. The working power supply 113 is transmitted to the ground via the third end D and the second end S of the first switching transistor 111. For the second switching transistor 112, since the first switching transistor 111 is in a conducting state, the working power supply 113 is transferred away from the first switching transistor 111, so the second switching transistor 112 is short-circuited by the first switching transistor 111. That is, the gate G (the first end) of the second switching transistor 112 presents a low level, the third end D of the second switching transistor 112 presents the power supply voltage VP (i.e., less than or equal to 3.3V), and the second end S of the second switching transistor 112 presents a low level. Then, VGS is less than or equal to the threshold voltage VT1 of the second switching transistor 112, and the second switching transistor 112 is in a non-conducting state, that is, the RTC battery circuit 100 is open-circuited from the processor 12.

[0068] Figure 3 Another circuit diagram of the battery voltage detection circuit provided by an embodiment of the present invention. In some embodiments, referring to Figure 3 , both the first MOS transistor and the second MOS transistor are PMOS transistors.

[0069] Figure 4 The second structural schematic diagram of the voltage detection circuit provided by an embodiment of the present invention. In some embodiments, referring to Figure 4 , the controller further includes a digital-to-analog conversion module, and the digital-to-analog conversion module is used to convert the voltage of the output node into a digital signal.

[0070] Figure 5 The third structural schematic diagram of the voltage detection circuit provided by an embodiment of the present invention.

[0071] In some embodiments, referring to Figure 5 , the controller further includes: a comparison module, which is used to compare the current voltage of the received output node with a preset voltage; an alarm module, which is used to send an alarm prompt message when the comparison signal is abnormal. The comparison signal being abnormal means that the current voltage of the output node of the RTC battery is less than the preset voltage.

[0072] In some embodiments, there is a diode between the third end and the second end of the first switching transistor 111 to protect the first switching transistor 111 through the diode.

[0073] In some embodiments, there is a diode between the third end and the second end of the second switching transistor 112.

[0074] In some embodiments, the first switching transistor 111 is further configured to receive a shutdown signal. When the shutdown signal is received, a stop signal is output to the second switching transistor 112. The second switching transistor 11 is further configured to control the RTC battery circuit 100 to be open-circuited from the processor 120 after receiving the stop signal.

[0075] In some embodiments, it further includes: a logic judgment circuit. The logic judgment circuit is connected to the RTC battery voltage value acquisition module and is configured to compare the RTC battery voltage value with a reference voltage and output a judgment signal. Based on the logic judgment circuit, the power supply voltage can be automatically detected. Thus, the manual judgment process of the power supply voltage can be omitted, thereby improving the working efficiency.

[0076] In some embodiments, it further includes: an alarm circuit. The alarm circuit is electrically connected to the logic judgment circuit and is configured to receive the judgment signal and issue an alarm signal. The alarm circuit can directly alarm the technical personnel about the judgment signal output by the logic judgment circuit, avoiding the situation of omission and forgetting by the technical personnel, and can detect whether the RTC battery is properly configured promptly and quickly.

[0077] It should be noted that the embodiments of the present invention do not limit the logic judgment circuit and the alarm circuit. It is only required that the logic judgment circuit is used to compare the RTC battery voltage value with the reference voltage and output a judgment signal, and the alarm circuit is used to receive the judgment signal and issue an alarm signal. For example, the logic judgment circuit may include a comparison circuit and a switching module, and the alarm circuit includes a transistor and an LED lamp or a buzzer, etc.

[0078] In some embodiments, it further includes: an adjustment circuit. The adjustment circuit is connected to the switch detection circuit and the RTC battery voltage value acquisition module and is configured to eliminate the error generated by the RTC battery circuit.

[0079] The RTC automatic detection circuit provided by the embodiments of the present invention can automatically detect the RTC battery voltage. The RTC detection circuit can detect the RTC battery voltage, which can reduce a manual inspection station, ensure no missed detection, meet the automation requirements of testing, and greatly save labor and time costs.

[0080] Correspondingly, the embodiments of the present invention further provide an electronic device, including the battery voltage detection circuit described in any one of the above embodiments. Figure 6A schematic structural diagram of an electronic device provided by an embodiment of the present utility model.

[0081] In some embodiments, the electronic device may be an electronic device such as a desktop computer, a laptop computer, a tablet computer, a personal digital assistant, or a smart phone.

[0082] Figure 7 A flowchart of an RTC battery voltage detection method provided by an embodiment of the present utility model.

[0083] Correspondingly, an embodiment of the present utility model further provides an RTC battery voltage detection method. Refer to Figure 7 , the detection method includes: setting an RTC battery voltage detection circuit and an RTC battery circuit; when the controller receives an RTC battery voltage acquisition command, providing an enable signal and transmitting it to the first switching tube; when the first switching tube receives the enable signal, outputting a switch control signal to the second switching tube; when the first switching tube receives the enable signal, outputting a switch control signal to the second switching tube; when the first switching tube receives the enable signal, outputting a switch control signal to the second switching tube; the controller detects the voltage of the output node.

[0084] In some embodiments, after obtaining the RTC battery voltage value, it further includes: obtaining the normal operating voltage and the low voltage alarm threshold of the RTC battery, and determining the value of the reference voltage in the logic judgment circuit according to the normal operating voltage and the low voltage alarm threshold of the RTC battery; the logic judgment circuit receives the RTC battery voltage value, compares the RTC battery voltage value with the reference voltage and outputs a judgment signal; the alarm circuit receives the judgment signal and issues an alarm signal.

[0085] Those of ordinary skill in the art can understand that the above embodiments are specific embodiments for implementing the present utility model. In actual applications, various changes can be made in form and details without departing from the spirit and scope of the present utility model. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present utility model. Therefore, the protection scope of the present utility model should be subject to the scope defined by the claims.

Claims

1. A voltage detection circuit for connecting to an output node of an RTC battery, characterized in that: include: A controller, the controller is used to provide an enable signal, wherein the enable signal is used to control the on or off of the first switch tube; The switch circuit includes the first switch tube and a second switch tube, the first end of the first switch tube is connected to the controller, the second end of the first switch tube is connected to the first end of the second switch tube, the second end of the second switch tube is connected to the controller, the third end of the second switch tube is connected to the output node, and the second switch tube is turned on when the first switch tube is turned off, so that the controller can detect the voltage of the output node.

2. The voltage detection circuit according to claim 1, characterized in that: The first switch tube includes a first MOS tube, the gate of the first MOS tube is the first end of the first MOS tube, the first end of the first MOS tube is connected to the controller, the third end of the first MOS tube is grounded, and the second end of the first MOS tube is connected to the second switch tube.

3. The voltage detection circuit according to claim 2, characterized in that: The second switch tube includes a second MOS tube, a gate of the second MOS tube is connected to a working power supply, the gate of the second MOS tube is the first end of the second MOS tube, and is also connected to the second end of the first MOS tube, the third end of the second MOS tube is connected to the output node, and the second end of the second MOS tube is connected to the controller.

4. The voltage detection circuit according to claim 3, characterized in that: The second end of the first MOS tube is also electrically connected to the working power supply.

5. The voltage detection circuit according to claim 3, characterized in that: The first MOS tube and the second MOS tube are both NMOS tubes.

6. The voltage detection circuit according to claim 3, characterized in that: The first MOS tube and the second MOS tube are both PMOS tubes.

7. The voltage detection circuit according to claim 1, characterized in that: When the first switch tube is turned on, the second switch tube is turned off, so that the output node is disconnected from the controller.

8. The voltage detection circuit according to claim 1, characterized in that: The controller further comprises a digital-to-analog conversion module, and the digital-to-analog conversion module is used to convert the voltage of the output node into a digital signal.

9. The voltage detection circuit according to claim 1, characterized in that: The controller also includes: a comparison module for comparing the received current voltage of the output node with a preset voltage; an alarm module for issuing an alarm prompt message when the comparison signal is abnormal, and the abnormal comparison signal means that the current voltage of the output node of the RTC battery is less than the preset voltage.

10. An electronic device, characterized in that: The invention comprises an RTC battery and a voltage detection circuit as claimed in any one of claims 1 to 9.

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