A battery temperature control circuit, a battery temperature control device and an electric device

Abstract

The application relates to the technical field of battery protection circuits, in particular to a battery temperature control circuit, a battery temperature control device and an electric device. The battery end circuit is connected with the device end circuit through a thermosensitive voltage division circuit. When the temperature of the battery end circuit is normal, the voltage division voltage of the thermosensitive voltage division circuit can reach the conduction voltage of the second control circuit, at this time, the second control circuit and the first control circuit can be short-circuited, the device end power-on key forms a loop, and the device can normally enter a power-on state. When the temperature of the battery end circuit is too high, the voltage division voltage of the thermosensitive voltage division circuit cannot reach the conduction voltage of the second control circuit, at this time, the second control circuit is in an off state, the device end power-on key has no loop, the device is disconnected and cannot enter the power-on state. The application can quickly detect the abnormal condition of the rising battery temperature, and the device can be disconnected in advance to prevent the device from working in an unsafe condition for a long time.

Description

Technical Field

[0001] This application relates to the field of battery protection circuit technology, specifically to a battery temperature control circuit, a battery temperature control device, and an electrical appliance. Background Technology

[0002] For mobile phones and other devices, as functions increase, the integration level is not yet perfect for high-power, cross-industry integration, and cannot keep up with the requirements of multiple functions. Low integration level leads to an increase in discrete circuits, which in turn causes the overall device temperature to rise rapidly. The battery of a mobile device supplies power to the entire device. When the battery overheats abnormally, if the device is not handled promptly, it may cause some safety and regulatory issues. Summary of the Invention

[0003] This application provides a battery temperature control circuit, a battery temperature control device, and an electrical appliance, which effectively solves the safety hazard caused by the continuous heating of the battery during the use of existing equipment.

[0004] According to one aspect of this application, one embodiment provides a battery temperature control circuit, including a device-side circuit and a battery-side circuit. The device-side circuit includes a first spring contact, a second spring contact, a first control circuit, and a second control circuit; the first spring contact is connected to a first high-level signal terminal, and the second spring contact is connected to a first terminal of the first control circuit and a first terminal of the second control circuit, respectively; the second terminal of the first control circuit is connected to a second high-level signal terminal, and the second terminal of the second control circuit is connected to the battery-side circuit. The battery terminal circuit includes a power supply, a low-dropout regulator, and a thermistor voltage divider circuit; the thermistor voltage divider circuit is connected to the power supply through the low-dropout regulator, and the second terminal of the second control circuit is connected to the thermistor voltage divider circuit. When the voltage of the thermistor voltage divider circuit reaches the conduction threshold of the second control circuit, the second control circuit is grounded.

[0005] In one feasible implementation, the first control circuit includes a first N-MOSFET, the gate of the first N-MOSFET is connected to the second high-level signal terminal, the drain of the first N-MOSFET is connected to the second contact spring, and the source of the first N-MOSFET is grounded.

[0006] In one feasible implementation, the second control circuit includes a second N-MOSFET, the gate of which is connected to the thermistor voltage divider circuit via a first communication interface, the drain of which is connected to the second contact spring, and the source of which is grounded.

[0007] In one feasible implementation, the device-side circuit further includes an electrostatic discharge (ESD) protection element, one end of which is connected to the gate of the second N-MOSFET, and the other end of which is grounded.

[0008] In one feasible implementation, the device-side circuit further includes a signal detection terminal, and the battery-side circuit further includes a voltage divider output terminal; the signal detection terminal is used to receive and detect the output voltage of the voltage divider output terminal.

[0009] In one feasible implementation, the thermistor voltage divider circuit includes a fixed resistor and a thermistor; the first end of the fixed resistor is connected to the output terminal of the low dropout regulator, the second end of the fixed resistor is connected to the first end of the thermistor, and the second end of the thermistor is grounded; the gate of the second N-MOSFET is connected to the first end of the thermistor through a first communication interface.

[0010] In one feasible implementation, the battery terminal circuit further includes a first capacitor, a first terminal of which is connected to a first terminal of the fixed resistor, and a second terminal of which is grounded.

[0011] In one feasible implementation, the battery terminal circuit further includes a second capacitor, the first terminal of which is connected to the input terminal of the low dropout regulator, and the second terminal of which is grounded.

[0012] According to one aspect of this application, one embodiment provides a battery temperature control device, including the battery temperature control circuit described above.

[0013] According to one aspect of this application, one embodiment provides an electrical device including a battery temperature control device as described above.

[0014] According to the above embodiments, a battery temperature control circuit, a battery temperature control device, and an electrical device are disclosed. The battery temperature control circuit of this solution includes a device-side circuit and a battery-side circuit. Specifically, the battery-side circuit is connected to the device-side circuit via a thermistor voltage divider circuit. In practical applications, when the temperature of the battery-side circuit is within the normal temperature range, the voltage divided by the thermistor voltage divider circuit can reach the conduction voltage of the second control circuit in the device-side circuit. At this time, the second control circuit and the first control circuit can be short-circuited by pressing a spring, forming a loop with the device-side power button, thus ensuring that the device can normally enter the power-on state. When the temperature of the battery-side circuit is too high, the voltage divided by the thermistor voltage divider circuit cannot reach the conduction voltage of the second control circuit in the device-side circuit. At this time, the second control circuit is in the off state, and the device-side power button has no loop, causing the device to disconnect and unable to enter the power-on state. By adopting the above solution of this application, abnormally high battery temperatures can be detected quickly, thereby preventing abnormal devices from operating under unsafe conditions for extended periods and minimizing or preventing potential losses. Attached Figure Description

[0015] Figure 1 This is a circuit diagram of a battery temperature control circuit provided in this embodiment.

[0016] Figure labels: 10, device-side circuit; 20, battery-side circuit. Detailed Implementation

[0017] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments. Similar elements in different embodiments are referred to by related similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of the present application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to the present application are not shown or described in the specification. This is to avoid obscuring the core parts of the present application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0018] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments, and the operational steps involved in each embodiment can also be rearranged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the specification and drawings are only for clearly describing a particular embodiment and do not imply that they represent the necessary components and / or order.

[0019] The serial numbers assigned to components in this document, such as "first" and "second," are used only to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages).

[0020] like Figure 1 As shown, this embodiment provides a battery temperature control circuit, including a device-side circuit 10 and a battery-side circuit 20. The device-side circuit 10 includes a first spring key1, a second spring key2, a first control circuit, and a second control circuit. The first spring key1 is connected to a first high-level signal terminal a, and the second spring key2 is connected to the first terminal of the first control circuit and the first terminal of the second control circuit, respectively. The second terminal of the first control circuit is connected to a second high-level signal terminal b, and the second terminal of the second control circuit is connected to the battery-side circuit 20. The battery-side circuit 20 includes a power supply VBAT, a low-dropout regulator U1, and a thermistor voltage divider circuit. The thermistor voltage divider circuit is connected to the power supply VBAT through the low-dropout regulator U1, and the second terminal of the second control circuit is connected to the thermistor voltage divider circuit. When the voltage of the thermistor voltage divider circuit reaches the conduction threshold of the second control circuit, the second control circuit is grounded.

[0021] In this embodiment, in practical application, the first spring contact key1 is connected to the first high-level signal terminal a. Before the device is powered on, this signal is high. When the first spring contact key1 connected to the first high-level signal terminal a is normally shorted to the second spring contact key2 connected to the conducting second control circuit, the device can normally enter the power-on state. Specifically, the conducting second control circuit refers to the second spring contact key2 being grounded through the conducting second control circuit. In actual operation, pressing the power button shorts the first spring contact key1 and the second spring contact key2, ensuring a normal circuit at the power button's GND terminal, thus enabling normal power-on. Repeating this action when powering off will enter the power-off state.

[0022] Specifically, to enable the second control circuit, its control terminal is connected to the thermal voltage divider circuit of the battery terminal circuit 20. The second control circuit is turned on or off based on the voltage division of the thermal voltage divider circuit. Specifically, when the surface temperature of the battery terminal is too high, the voltage of the thermal voltage divider circuit changes according to the external temperature. When the temperature is too high, the voltage division decreases, and this decreased voltage cannot reach the turn-on voltage of the second control circuit. Therefore, a normal circuit cannot be formed at the device power button GND terminal, causing the device to disconnect from the battery terminal and preventing the device from working properly. When the surface temperature of the battery terminal is normal, the voltage division increases, reaching the turn-on voltage of the second control circuit. Therefore, a normal circuit can be formed at the device power button GND terminal, allowing the device to enter the power-on state normally.

[0023] Furthermore, after the device is powered on normally, the second high-level signal terminal b will also output a high-level signal. At this time, the control terminal of the first control circuit is connected to the second high-level signal terminal b, so the first control circuit will also be in a conducting state. When the first control circuit is conducting, the device's power button control is taken over by the device itself, and the device can then enter normal working state. After the device is powered on, the power-off operation is taken over by the motherboard CPU circuit, and the battery terminal circuit 20 cannot control the power-on and power-off operations.

[0024] As a further improvement to this embodiment, the device-side circuit 10 also includes a signal detection terminal c, and the battery-side circuit 20 also includes a voltage divider output terminal; the signal detection terminal c is used to receive and detect the output voltage of the voltage divider output terminal.

[0025] Specifically, after the device takes over the power button control, the signal detection terminal c of the device-side circuit 10 detects the voltage divider of the battery-side circuit 20. The motherboard CPU circuit on the device side can analyze and compare the temperature value based on the feedback of this voltage divider. If the analysis shows that the temperature rises after powering on, since the device side has now taken over the power button control, the motherboard CPU circuit can display a prompt message according to the initial software settings to indicate that the battery temperature is too high. Then, manual operation can be performed to decide whether to enter the shutdown or other states.

[0026] In the above embodiments, the first high-level signal terminal a, the second high-level signal terminal b, and the signal detection terminal c are all connected to the motherboard CPU circuit of the device.

[0027] Furthermore, the first control circuit includes a first N-MOSFET Q1, the gate of which is connected to a second high-level signal terminal b, the drain of which is connected to a second contact spring, and the source of which is grounded. The second control circuit includes a second N-MOSFET Q2, the gate of which is connected to a thermistor voltage divider circuit via a first communication interface, the drain of which is connected to the second contact spring, and the source of which is grounded.

[0028] Specifically, after the mobile device is powered on normally, the second high-level signal terminal b outputs a high level, turning on the first N-MOSFET Q1. Once Q1 is on, the device normally takes over the power button control. When the voltage division of the thermal voltage divider circuit meets the conduction condition of the second N-MOSFET Q2, Q2 enters the conduction state, and the power button operates normally. Simultaneously, when the high level of the first high-level signal terminal a is normally pulled low, the device enters the power-on state. When the battery temperature is too high, the voltage division of the thermal voltage divider circuit at the battery end cannot meet the conduction condition of the second N-MOSFET Q2. In this case, because the voltage divider controls the power button circuit at the device end, when the battery temperature is abnormal, the device cannot be powered on normally by pressing the power button or the power button becomes malfunctioning.

[0029] In some embodiments, the device-side circuit 10 further includes an electrostatic discharge (ESD) protection element T, one end of which is connected to the gate of the second N-MOSFET, and the other end of which is grounded. Specifically, the ESD protection element T can effectively release static electricity and prevent damage to the device.

[0030] Furthermore, the thermistor voltage divider circuit includes a fixed resistor and a thermistor; the first end of the fixed resistor is connected to the output terminal of the low dropout voltage regulator, the second end of the fixed resistor is connected to the first end of the thermistor, and the second end of the thermistor is grounded; the gate of the second N-MOSFET is connected to the first end of the thermistor through the first communication interface.

[0031] Specifically, after the low-dropout regulator U1 steps down the power supply VBAT to the set voltage, a voltage divider is formed by a fixed resistor R and a thermistor RT. When the ambient temperature of the thermistor RT is too high, its resistance changes according to the temperature. If the temperature is too high, the resistance of the thermistor RT decreases linearly, resulting in a decrease in the voltage output of the voltage divider (i.e., a decrease in the gate voltage of the second N-MOSFET Q2). Consequently, the second N-MOSFET Q2 is in the off state, and the power button on the device has no circuit, preventing normal power-on. If the temperature is normal, the resistance of the thermistor RT increases, resulting in an increase in the voltage output of the voltage divider (i.e., an increase in the gate voltage of the second N-MOSFET). This satisfies the turn-on voltage of the second N-MOSFET Q2, turning it on. When the power button is pressed at this time, a normal circuit is established at the GND terminal of the power button on the device, allowing the device to power on normally.

[0032] In some embodiments, the battery terminal circuit 20 further includes a first capacitor C1 and a second capacitor C2. The first terminal of the first capacitor C1 is connected to the first terminal of the fixed resistor R, and the second terminal of the first capacitor C1 is grounded. The first terminal of the second capacitor C2 is connected to the input terminal of the low dropout regulator U1, and the second terminal of the second capacitor C2 is grounded.

[0033] Specifically, in this embodiment, the first capacitor C1 and the second capacitor C2 are both filter capacitors used to filter out high-frequency noise in the power supply VBAT, so that the power supply VBAT voltage is output stably.

[0034] also, Figure 1 P1, P3, P5, and P8 are the communication interfaces on the device side, while P2, P4, P6, and P7 are the communication interfaces on the battery side corresponding to the device side.

[0035] This embodiment provides a battery temperature control device, including the battery temperature control circuit described above. Since the battery temperature control circuit has been described in detail in the above embodiments, it will not be repeated here.

[0036] This embodiment provides an electrical device including the battery temperature control device described above. Specifically, the electrical device in this embodiment includes a battery temperature control device and a battery temperature control circuit. Since the battery temperature control device and battery temperature control circuit have been described in the above embodiments, they will not be repeated here.

[0037] The above-described specific examples are for illustrative purposes only and are not intended to limit the scope of this invention. Those skilled in the art to which this invention pertains can make various simple deductions, modifications, or substitutions based on the concept of this invention.

Claims

1. A battery temperature control circuit, characterized in that, This includes both the device-side circuitry and the battery-side circuitry. The device-side circuit includes a first spring contact, a second spring contact, a first control circuit, and a second control circuit; the first spring contact is connected to a first high-level signal terminal, and the second spring contact is connected to a first terminal of the first control circuit and a first terminal of the second control circuit, respectively; the second terminal of the first control circuit is connected to a second high-level signal terminal, and the second terminal of the second control circuit is connected to the battery-side circuit. The battery terminal circuit includes a power supply, a low-dropout regulator, and a thermistor voltage divider circuit; the thermistor voltage divider circuit is connected to the power supply through the low-dropout regulator, and the second terminal of the second control circuit is connected to the thermistor voltage divider circuit. When the voltage of the thermistor voltage divider circuit reaches the conduction threshold of the second control circuit, the second control circuit is grounded.

2. The battery temperature control circuit as described in claim 1, characterized in that, The first control circuit includes a first N-MOSFET, the gate of the first N-MOSFET is connected to the second high-level signal terminal, the drain of the first N-MOSFET is connected to the second contact spring, and the source of the first N-MOSFET is grounded.

3. The battery temperature control circuit as described in claim 1, characterized in that, The second control circuit includes a second N-MOSFET, the gate of which is connected to the thermistor voltage divider circuit through a first communication interface, the drain of which is connected to the second contact spring, and the source of which is grounded.

4. The battery temperature control circuit as described in claim 3, characterized in that, The device-side circuit also includes an electrostatic discharge (ESD) protection element, one end of which is connected to the gate of the second N-MOSFET, and the other end of which is grounded.

5. The battery temperature control circuit as described in claim 1, characterized in that, The device-side circuit also includes a signal detection terminal, and the battery-side circuit also includes a voltage divider output terminal; the signal detection terminal is used to receive and detect the output voltage of the voltage divider output terminal.

6. The battery temperature control circuit as described in claim 3, characterized in that, The thermistor voltage divider circuit includes a fixed resistor and a thermistor; the first end of the fixed resistor is connected to the output terminal of the low dropout voltage regulator, the second end of the fixed resistor is connected to the first end of the thermistor, and the second end of the thermistor is grounded. The gate of the second N-MOSFET is connected to the first terminal of the thermistor through the first communication interface.

7. The battery temperature control circuit as described in claim 6, characterized in that, The battery terminal circuit also includes a first capacitor, the first end of which is connected to the first end of the fixed resistor, and the second end of the first capacitor is grounded.

8. The battery temperature control circuit as described in claim 1, characterized in that, The battery terminal circuit also includes a second capacitor, the first end of which is connected to the input terminal of the low dropout regulator, and the second end of which is grounded.

9. A battery temperature control device, characterized in that, Includes a battery temperature control circuit as described in any one of claims 1-8.

10. An electrical appliance, characterized in that, Includes the battery temperature control device as described in claim 9.

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