CN109038487A - A kind of temperature protection circuit and charging base for charging base - Google Patents
A kind of temperature protection circuit and charging base for charging base Download PDFInfo
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- CN109038487A CN109038487A CN201811259963.8A CN201811259963A CN109038487A CN 109038487 A CN109038487 A CN 109038487A CN 201811259963 A CN201811259963 A CN 201811259963A CN 109038487 A CN109038487 A CN 109038487A
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- 238000000034 method Methods 0.000 abstract description 29
- 230000008569 process Effects 0.000 abstract description 27
- 238000013021 overheating Methods 0.000 abstract description 2
- 230000007423 decrease Effects 0.000 description 5
- 238000013461 design Methods 0.000 description 5
- 230000009471 action Effects 0.000 description 3
- 230000009977 dual effect Effects 0.000 description 3
- 238000009529 body temperature measurement Methods 0.000 description 2
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H5/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal non-electric working conditions with or without subsequent reconnection
- H02H5/04—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal non-electric working conditions with or without subsequent reconnection responsive to abnormal temperature
- H02H5/042—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal non-electric working conditions with or without subsequent reconnection responsive to abnormal temperature using temperature dependent resistors
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- H02J7/0088—
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- Charge And Discharge Circuits For Batteries Or The Like (AREA)
Abstract
The invention discloses a kind of temperature protection circuits and charging base for charging base, including temperature sensing circuit, comparison circuit and charge protection chip；The temperature sensing circuit carries out temperature detection to the electronic product of connection charging base, and according to the corresponding detection voltage of temperature rise variation output；The comparison circuit receives the detection voltage and is compared with reference voltage, to generate temperature protection signal when the temperature of the electronic product is more than secure threshold；The charge protection chip connects the comparison circuit, and the voltage output of charging base is turned off when receiving the temperature protection signal of comparison circuit output, carries out overheating protection to electronic product.Charging base of the invention can during the charging process electronic product temperature rise be more than secure threshold when, automatically shut down the voltage output of charging base, and after the temperature of electronic product restores normal, charging process can be restored automatically, so that the charging process of electronic product is more safe and reliable.
Description
Technical Field
The invention belongs to the technical field of charging devices, and particularly relates to a circuit design applied to a charging base.
Background
Along with the rapid development of electronic technology, wearing type electronic equipment is increasingly numerous, for example intelligent wrist-watch, intelligent bracelet etc. have brought very big facility for people's daily life. At present, a rechargeable battery is arranged in wearable electronic equipment to supply power to a system circuit of the equipment, and the rechargeable battery can be charged and stored energy by using an external charger (a plug type or a base type).
Along with the continuous increase of battery capacity in wearable electronic equipment, the charging current also increases, inevitably leads to the continuous rise of temperature of wearable equipment in the charging process. The current charger only detects a charging power supply and charging current and makes corresponding overvoltage and overcurrent protection measures in the charging process of the wearable device, and the charging temperature does not have a corresponding protection function, so that hidden dangers that the wearable device scalds a user due to overhigh charging temperature rise, the device is damaged and even the device is ignited and the like exist, and the use safety of the user is seriously influenced.
Disclosure of Invention
The invention provides a temperature protection circuit suitable for a charging base in order to make up the defect that the conventional charger does not have a charging temperature protection function, and the temperature protection circuit can be used for detecting the temperature rise of an electronic product in the charging process by using the charging base and carrying out overheat protection on the electronic product.
In order to solve the technical problems, the invention adopts the following technical scheme:
in one aspect, the invention provides a temperature protection circuit for a charging base, which comprises a temperature detection circuit, a comparison circuit and a charging protection chip; the temperature detection circuit detects the temperature of the electronic product connected with the charging base and outputs corresponding detection voltage according to the temperature rise change; the comparison circuit receives the detection voltage and compares the detection voltage with a reference voltage so as to generate a temperature protection signal when the temperature of the electronic product exceeds a safety threshold value; the charging protection chip is connected with the comparison circuit, and the voltage output of the charging base is switched off when the temperature protection signal output by the comparison circuit is received, so that the electronic product is subjected to overheat protection.
Preferably, the temperature detection circuit is provided with a thermistor and a voltage dividing resistor, the thermistor and the voltage dividing resistor are connected to form a voltage dividing network, and the detection voltage is output through a voltage dividing node of the voltage dividing network.
Preferably, the voltage dividing network is connected between a charging power supply required by the electronic product generated by converting the charging base and the ground, and the detection voltage is generated by dividing the voltage of the charging power supply.
As a preferred circuit design of the comparison circuit, the comparison circuit is provided with a comparator, the non-inverting input end of the comparator is connected with the charging power supply through the divider resistor and is grounded through the thermistor, the thermistor is a negative temperature coefficient thermistor, and the inverting input end of the comparator is connected with the reference voltage to output a low-level effective temperature protection signal.
As another preferred circuit design of the comparison circuit, the comparison circuit is provided with a comparator, an inverting input end of the comparator is connected with the charging power supply through the voltage dividing resistor and is grounded through the thermistor, the thermistor is a positive temperature coefficient thermistor, and a non-inverting input end of the comparator is connected with the reference voltage to output a low-level effective temperature protection signal.
In order to enable the temperature protection signal output by the comparator to control the charging protection chip to execute an overheat protection action, the input end of the charging protection chip is designed to receive the charging power supply, the output end of the charging protection chip is connected with the charging interface, and the enabling end of the charging protection chip is respectively connected with the charging power supply and the output end of the comparator; the charging protection chip is enabled at a high level, and is controlled by the charging power supply to enter an enabled state when the temperature of the electronic product is lower than a safety threshold, so that the input end and the output end are controlled to be communicated, the charging power supply is transmitted to a charging interface, and the electronic product is charged; when the comparator outputs a low-level effective temperature protection signal, the input end and the output end are controlled to be disconnected, the charging power supply is blocked from conveying to the charging interface, the temperature rise of the electronic product is limited by adopting a charging ending mode, and the temperature protection of the electronic product is realized.
As a preferable generation method of the charging power supply, a rectification circuit and a direct current conversion circuit are provided in the charging base, and the rectification circuit rectifies an alternating current power supply connected to the charging base into a direct current power supply and outputs the direct current power supply to the direct current conversion circuit so as to convert and generate the charging power supply.
In order to further improve the safety of the charging process of the electronic product, the charging protection chip has a current limiting end which is connected with a configuration resistor, and the current threshold of the charging protection chip is adjusted by adjusting the resistance value of the configuration resistor; when the charging protection chip detects that the charging current flowing through the charging protection chip is larger than the current threshold value, the voltage output of the charging base is turned off, the charging process is stopped, the phenomenon that the temperature rise of the electronic product is too high due to the fact that the charging current is too large is avoided, and the charging safety of the electronic product is ensured by adopting a temperature measurement and current limiting dual measure.
In order to avoid frequent starting and stopping in the charging process and damage to electronic products, the output end of the comparison circuit is preferably connected with a delay capacitor, and the delay time of the overheat protection action is adjusted by adjusting the capacitance value of the delay capacitor.
In another aspect, the invention further provides a charging base, which includes a housing and a charging interface arranged on the housing and used for connecting an electronic product, wherein a temperature detection circuit, a comparison circuit and a charging protection chip are packaged in the housing; the temperature detection circuit detects the temperature of the electronic product connected with the charging base and outputs corresponding detection voltage according to the temperature rise change; the comparison circuit receives the detection voltage and compares the detection voltage with a reference voltage so as to generate a temperature protection signal when the temperature of the electronic product exceeds a safety threshold value; the charging protection chip is connected with the comparison circuit, and the voltage output of the charging base is switched off when the temperature protection signal output by the comparison circuit is received, so that the electronic product is subjected to overheat protection.
In order to improve the sensitivity of temperature rise detection of the electronic product, the temperature detection circuit is provided with the thermistor, and the thermistor is preferably arranged on the shell and at a position close to the charging interface, so that when the electronic product is connected to the charging interface of the charging base, the temperature change of the electronic product can be timely and accurately sensed.
Compared with the prior art, the invention has the advantages and positive effects that: the charging base can monitor the temperature change of the electronic product in real time in the charging process, and can automatically turn off the voltage output of the charging base when the temperature rise of the electronic product exceeds a safety threshold, thereby avoiding the potential safety hazard caused by overhigh temperature rise of the electronic product in the heavy-current charging process, enabling the temperature of the electronic product to be always maintained in an acceptable range in the charging process, and remarkably improving the safety and reliability of the charging process of the electronic product. In addition, the charging base can automatically recover the charging process after the temperature of the electronic product is recovered to be normal, the charging power supply is continuously output to charge the electronic product, the intelligent level of the charging base is improved while the temperature protection function is added to the charging base, and the use experience of a user is improved. The temperature protection function of the charging base is realized by adopting a hardware circuit, and the temperature protection circuit does not depend on software control, so that the working reliability of the circuit is higher.
Other features and advantages of the present invention will become more apparent from the detailed description of the embodiments of the present invention when taken in conjunction with the accompanying drawings.
Drawings
FIG. 1 is a schematic block circuit diagram of one embodiment of a temperature protection circuit for a charging base in accordance with the present invention;
FIG. 2 is a detailed circuit schematic of one embodiment of the temperature protection circuit shown in FIG. 1;
fig. 3 is a detailed circuit schematic block diagram of another embodiment of the temperature protection circuit shown in fig. 1.
Detailed Description
The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.
In this embodiment, in order to add a temperature protection function to the charging base, a temperature protection circuit is added to the charging base, and as shown in fig. 1, the temperature protection circuit includes a temperature detection circuit, a comparison circuit, a charging protection chip, and the like. In this embodiment, the charging base may be a charging base for charging the wearable electronic device, or may be a charging base for charging other electronic products such as a mobile phone and a tablet personal computer, which have a built-in rechargeable battery. Wherein the temperature detection circuit is provided with a temperature sensing element, preferably mounted on the charging baseThe shell is just attached to the electronic product or close to the electronic product when the electronic product is placed in the charging base, for example, the position of a charging interface close to the charging base is arranged, so that the temperature sensing element can timely and accurately sense the temperature rise change of the electronic product inserted into the charging base, and the temperature detection circuit can generate a detection voltage Vo corresponding to the temperature detection voltage Vo according to the detected product temperature and output the detection voltage Vo to the comparison circuit. The reference voltage V is determined in advance according to the detection voltage generated by the temperature detection circuit when the temperature of the electronic product reaches the safety threshold valueREFThe comparison circuit is used for comparing the detection voltage Vo and the reference voltage V output by the temperature detection circuit in the actual application processREFA comparison is made to generate an effective temperature protection signal V when the temperature of the electronic product exceeds its safety thresholdENAnd sending the data to the charging protection chip. The charging protection chip is connected in the charging base and used for conveying a charging power supply VCHGIn the power output line of (3), receiving the effective temperature protection signal V output by the comparison circuitENWhen the charging device is used, the power output circuit is automatically cut off to cut off the voltage output of the charging base, and the electronic product is subjected to overheat protection by adopting a charging ending mode, so that the charging safety of the electronic product is ensured.
In the present embodiment, the charging power supply VCHGThe alternating current commercial power can be converted and generated by a rectifying circuit and a voltage stabilizing circuit which are arranged in the charging base. Namely, the charging base is connected with alternating current commercial power, receives 220V alternating current power and transmits the power to the rectifying circuit so as to generate high-voltage direct current power through rectification and transmit the high-voltage direct current power to the direct current conversion circuit. The dc conversion circuit may include a dc voltage processing circuit such as a transformer, a filter circuit, and a regulator circuit, and converts the high-voltage dc power output by the rectifier circuit into a low-voltage dc power required for charging the electronic product, such as a +5V or a +9V or a +12V charging power VCHGAnd the data is transmitted to the charging interface through the charging protection chip. The charging interface is arranged on the shell of the charging base and exposed, when the electronic product is placed in the charging base, the charging interface of the electronic product can be just butted with the charging interface on the charging base to receive the power transmission of the charging baseOutgoing charging power supply VCHGAnd the rechargeable battery in the electronic product is charged to store energy.
In the temperature protection circuit of the present embodiment, the reference voltage VREFThe charging power supply V can be connected with a voltage-dividing resistorCHGPartial pressure is obtained. As shown in fig. 2, voltage dividing resistors R107 and R105 may be disposed on the built-in circuit board of the charging base, one end of the voltage dividing resistor R107 is grounded through the voltage dividing resistor R105, and the other end is directly connected to the charging power supply VCHGOr the charging power supply V is connected through a current-limiting resistor R101CHG. The resistance values of the voltage dividing resistors R107 and R105 are configured such that the voltage at the intermediate node of the voltage dividing resistors R107 and R105 is equal to the reference voltage VREF. The intermediate node of the voltage dividing resistors R107 and R105 is connected to the comparison circuit or is connected to the comparison circuit via a resistor R115, and the reference voltage V is provided for the comparison circuitREF。
In the temperature detection circuit of the present embodiment, it is preferable that a thermistor is used as the temperature sensing element, and a voltage dividing network is formed by matching with the voltage dividing resistors R106 and R110 and connected to the charging power supply VCHGBetween the charging power supply V and the groundCHGAnd voltage division is carried out to generate a detection voltage Vo capable of reflecting the temperature change of the electronic product, and the detection voltage Vo is output to the comparison circuit. As a preferable design of this embodiment, the thermistor may be a thermistor RT101 of a negative temperature system, as shown in fig. 2; a thermistor RT102 of a positive temperature system can also be selected, as shown in FIG. 3.
When the temperature detection circuit is designed using the thermistor RT101 of the negative temperature system, as shown in fig. 2, one end of the thermistor RT101 may be grounded, and the other end may be connected to the charging power source V through the series-connected voltage dividing resistors R106, R110 (or further through the current limiting resistor R101)CHG. One voltage dividing node among the selection resistors RT101, R106 and R110 is connected with the comparison circuit and provides detection voltage Vo for the comparison circuit. In fig. 2, the voltage dividing node between the resistors R106 and R110 is selected to output the detection voltage Vo, which is transmitted to the comparison circuit through the resistor R113 to be compared with the reference voltage VREFA comparison is made.
In this embodiment, the comparison circuit is preferably formed by connecting the comparator U101 with a simple peripheral circuit, as shown in fig. 2. The detection voltage Vo is received by the non-inverting input terminal IN + of the comparator U101, and the reference voltage V is received by the inverting input terminal IN-of the comparator U101REFAnd filter capacitors C109 and C110 may be connected to the non-inverting input terminal IN + and the inverting input terminal IN-of the comparator U101, respectively, to increase the detection voltage Vo and the reference voltage V coupled to the comparator U101REFThe stability of (2) and then the reliability of the temperature protection action of the charging base is improved.
The thermistor RT101 of the negative temperature system decreases in resistance as the temperature of the electronic product increases, thereby causing the detection voltage Vo output through the voltage dividing node of the resistors R106, R110 to decrease as the temperature of the electronic product increases. Vo when the temperature of the electronic product is lower than the safety threshold>VREFThe comparator U101 outputs a high level signal to the enable terminal EN of the charge protection chip U102 because the potential of the non-inverting input terminal IN + is higher than the potential of the inverting input terminal IN-. The charging protection chip U102 of the present embodiment is enabled at a high level, and the enable terminal EN of the charging protection chip U102 may be further connected to the charging power supply V through the pull-up resistor R108CHGAnd connecting the input end IN of the charging protection chip U102 to the charging power supply VCHGAnd the output end OUT is connected to a power pin VBUS of a charging interface of the charging base. When the comparator U101 outputs a high level signal, the charging protection chip U102 enables to operate, controls the input end IN to be communicated with the output end OUT, and enables the charging power supply VCHGAnd the power supply pin VBUS is transmitted to the charging interface to charge the electronic product inserted into the charging base.
The electronic product can be accompanied by the temperature rise phenomenon in the charging process, and along with the temperature rise of the electronic product, the detection voltage Vo is reduced. Vo when the temperature of the electronic product inserted into the charging base exceeds a safety threshold<VREFThe comparator U101 outputs low-level effective temperature protection because the potential of the non-inverting input end IN + is lower than that of the inverting input end IN-Signal VENPulling down the potential of the enable end EN of the charging protection chip U102 to control the charging protection chip U102 to stop running, disconnecting the input end IN from the output end OUT, and cutting off the charging power supply VCHGAnd transmitting the voltage to the charging interface, namely, switching off the voltage output of the charging base, and stopping the charging process of the electronic product, so that the temperature of the electronic product is reduced, and the purpose of overheat protection of the electronic product is realized.
The detection voltage Vo rises along with the temperature reduction of the electronic product, and when the temperature of the electronic product is lower than a safety threshold value, the detection voltage Vo rises and exceeds a reference voltage VREF. At this time, the comparator U101 outputs a high level signal again, controls the charging protection chip U102 to enable operation again, recovers the voltage output of the charging base, and continues to charge the electronic product.
If the thermistor is replaced by a positive temperature coefficient thermistor RT102, as shown in FIG. 3, in order to obtain an effective temperature protection signal V of low levelENThen the detection voltage Vo needs to be transmitted to the inverting input IN-of the comparator U101, and the reference voltage V needs to be transmittedREFThe output terminal VOUT of the comparator U101 is connected to the enable terminal EN of the charge protection chip U102, and is transmitted to the non-inverting input terminal IN + of the comparator U101. Since the resistance of the positive temperature coefficient thermistor RT102 gradually increases with the increase of the temperature, the detection voltage Vo output through the voltage dividing node of the resistors R106 and R110 increases with the increase of the temperature of the electronic product. Vo when the temperature of the electronic product is lower than the safety threshold<VREFThe comparator U101 outputs a high level signal to keep the enabled running state of the charging protection chip U102, and the charging power supply V is connected with the charging protection chip U102CHGAnd the data is output to the electronic product through the charging interface to charge the electronic product. Vo when the temperature of the electronic product is higher than the safety threshold>VREFThe comparator U101 outputs a low-level effective temperature protection signal VENPulling down the potential of an enable end EN of the charging protection chip U102 to stop the charging protection chip U102 from running, controlling the charging protection chip U102 to disconnect an input end IN from an output end OUT, and switching off the voltage output of the charging base to realize temperature protection on the electronic product。
After the electronic product finishes the charging process, the temperature of the electronic product gradually drops, the detection voltage Vo gradually decreases, and when the temperature of the electronic product is lower than the safety threshold value, the Vo is gradually reduced<VREFAt this time, the comparator U101 outputs a high level signal again, controls the charging protection chip U102 to enable operation again, recovers the voltage output of the charging base, and continues to charge the electronic product.
In order to avoid the charging base from frequently performing the overheat protection operation, in the present embodiment, the output terminal VOUT of the comparator U101 is preferably connected to the delay capacitor CT, that is, the output terminal VOUT of the comparator U101 is grounded through the delay capacitor CT, as shown in fig. 2 and fig. 3, and the delay time of the overheat protection operation can be adjusted by adjusting the capacitance value of the delay capacitor CT.
The specific working principle is as follows: when the voltage at the inverting input IN-of the comparator U101 is higher than the voltage at the non-inverting input IN +, the comparator U101 outputs an active low temperature protection signal VENThat is, the output terminal VOUT of the comparator U101 is pulled low internally to ground. At this time, since the delay capacitor CT is fully charged with charges and the capacitor has a characteristic that the voltages at the two ends of the capacitor cannot change suddenly, the enable end EN of the charging protection chip U102 still maintains a high level and continues the current charging process. Then, the delay capacitor CT discharges through the output terminal VOUT of the comparator U101, so that the potential of the enable terminal EN of the charging protection chip U102 gradually decreases until the delay time t1, the potential of the enable terminal EN decreases to a low level, the voltage output of the charging base is turned off, and the charging process of the electronic product is ended. Within the delay time t1, if the temperature of the electronic product drops and falls below the safety threshold, the comparator U101 outputs a high level signal again to charge the delay capacitor CT, and the potential of the enable terminal EN of the charging protection chip U102 is kept high all the time, so that the charging process of the electronic product is continuous, the charging process cannot be frequently started or stopped due to the transient temperature rise of the electronic product, and the electronic product is protected to a certain extent.
Similarly, when the charging base is turned off due to the over-high temperature of the electronic productAfter the voltage is output, if the temperature of the electronic product is reduced and is recovered to be lower than the safety threshold, the comparator U101 outputs the high level again. At this time, due to the existence of the delay capacitor CT, the enable terminal EN of the charging protection chip U102 still maintains a low potential, and the charging power supply V is not output to the electronic productCHGAnd after the delay time t2, the voltage on the delay capacitor CT gradually rises, so that the potential of the enable end EN of the charging protection chip U102 becomes a high level, and the charging process of the electronic product is resumed. Within the delay time t2, if the temperature of the electronic product rises again and exceeds the safety threshold, the output terminal VOUT of the comparator U101 turns to a low level again, the delay capacitor CT is controlled to discharge, the potential of the enable terminal EN of the charging protection chip U102 is kept low all the time, the voltage output of the charging base is continuously turned off, frequent start and stop of the charging process due to short-time temperature drop of the electronic product cannot be caused, and the electronic product is prevented from being damaged due to frequent charging.
In addition, in order to further improve the temperature protection effect, the present embodiment provides a dual measure of temperature measurement and current limiting, which jointly determines the charging process of the charging base. Specifically, a temperature protection circuit is designed by using the charging protection chip U102 with a current limiting function, that is, the charging protection chip U102 has a current limiting end ILIM and is grounded through the configuration resistor R111. The current threshold value of the charging protection chip U102 can be adjusted by adjusting the resistance value of the configuration resistor R111, when the charging protection chip U102 detects that the charging current flowing through the output end OUT of the charging protection chip U is larger than the current threshold value, the input end IN and the output end OUT of the charging protection chip U are controlled to be disconnected no matter whether the temperature of the electronic product exceeds a safety threshold value or not, the voltage output of the charging base is cut off, the charging process of the electronic product is stopped, the phenomenon that the temperature rise of the electronic product is too high due to the fact that the charging current is too large is avoided, and dual.
The input end IN and the output end OUT of the charging protection chip U102 may be further connected with electrostatic protection diodes D107 and D102, respectively, to suppress electrostatic impact and protect the charging base.
According to the invention, a small amount of simple electronic devices are added in the charging base, and the charging base has a temperature protection function by adopting a pure hardware circuit design mode, so that the overheating protection can be performed on the electronic product in the charging process, and the charging base can automatically recover the charging process of the electronic product after the temperature of the electronic product is recovered to be normal, therefore, the intelligent degree is high, and the use is safe and reliable.
It is to be understood that the above description is not intended to limit the present invention, and the present invention is not limited to the above examples, and those skilled in the art may make modifications, alterations, additions or substitutions within the spirit and scope of the present invention.
Claims (10)
1. A temperature protection circuit for a charging base, comprising:
the temperature detection circuit is used for detecting the temperature of the electronic product connected with the charging base and outputting corresponding detection voltage according to the temperature rise change;
the comparison circuit receives the detection voltage and compares the detection voltage with a reference voltage to generate a temperature protection signal when the temperature of the electronic product exceeds a safety threshold value;
and the charging protection chip is connected with the comparison circuit, and is used for switching off the voltage output of the charging base when receiving the temperature protection signal output by the comparison circuit so as to perform overheat protection on the electronic product.
2. The temperature protection circuit for the charging base as claimed in claim 1, wherein a thermistor and a voltage dividing resistor are disposed in the temperature detection circuit, the thermistor and the voltage dividing resistor are connected to form a voltage dividing network, and the detection voltage is output through a voltage dividing node of the voltage dividing network.
3. The temperature protection circuit for the charging base as claimed in claim 2, wherein the voltage dividing network is connected between a charging power source required by the electronic product converted and generated by the charging base and ground, and divides the charging power source to generate the detection voltage.
4. The temperature protection circuit for a charging base according to claim 3, wherein a comparator is provided in the comparison circuit, wherein,
the non-inverting input end of the comparator is connected with the charging power supply through the divider resistor and is grounded through the thermistor, the thermistor is a thermistor with a negative temperature coefficient, and the inverting input end of the comparator is connected with the reference voltage and outputs a low-level effective temperature protection signal;
or,
the inverting input end of the comparator is connected with the charging power supply through the divider resistor and is grounded through the thermistor, the thermistor is a positive temperature coefficient thermistor, and the non-inverting input end of the comparator is connected with the reference voltage and outputs a low-level effective temperature protection signal.
5. The temperature protection circuit for the charging base as claimed in claim 4, wherein the input end of the charging protection chip receives the charging power supply, the output end of the charging protection chip is connected to the charging interface, and the enable end of the charging protection chip is respectively connected to the charging power supply and the output end of the comparator; the charging protection chip is enabled at a high level, and is controlled by the charging power supply to enter an enabled state when the temperature of the electronic product is lower than a safety threshold value, so that the input end and the output end are controlled to be communicated; and when the comparator outputs a low-level effective temperature protection signal, the input end and the output end are controlled to be disconnected.
6. The temperature protection circuit for the charging base as claimed in any one of claims 1 to 5, wherein the charging protection chip has a current-limiting terminal connected to a configuration resistor, and the current threshold of the charging protection chip is adjusted by adjusting the resistance of the configuration resistor; and when the charging protection chip detects that the charging current flowing through the charging protection chip is greater than the current threshold value, the voltage output of the charging base is cut off.
7. The temperature protection circuit for the charging base as claimed in any one of claims 1 to 5, wherein a delay capacitor is connected to an output end of the comparison circuit, and a capacitance value of the delay capacitor is adjusted to adjust a delay time of the overheat protection operation.
8. The temperature protection circuit for the charging base as claimed in any one of claims 3 to 5, wherein a rectification circuit and a DC conversion circuit are provided in the charging base, the rectification circuit rectifies an AC power supply connected to the charging base into a DC power supply and outputs the DC power supply to the DC conversion circuit, and the DC conversion circuit converts the DC power supply to generate the charging power supply.
9. A charging base, comprising a housing and a charging interface arranged on the housing and used for connecting an electronic product, wherein the temperature protection circuit for the charging base as claimed in any one of claims 1 to 8 is packaged in the housing.
10. The charging base of claim 9, wherein the temperature detection circuit comprises a thermistor mounted on the housing at a location adjacent to the charging interface.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811259963.8A CN109038487A (en) | 2018-10-26 | 2018-10-26 | A kind of temperature protection circuit and charging base for charging base |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811259963.8A CN109038487A (en) | 2018-10-26 | 2018-10-26 | A kind of temperature protection circuit and charging base for charging base |
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| CN109038487A true CN109038487A (en) | 2018-12-18 |
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| CN201811259963.8A Withdrawn CN109038487A (en) | 2018-10-26 | 2018-10-26 | A kind of temperature protection circuit and charging base for charging base |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110120691A (en) * | 2019-04-15 | 2019-08-13 | 出门问问信息科技有限公司 | A kind of charging base |
| CN111611130A (en) * | 2020-05-13 | 2020-09-01 | 上海龙旗科技股份有限公司 | Method, system and equipment for preventing burning of target interface |
| CN111614138A (en) * | 2020-05-25 | 2020-09-01 | 维沃移动通信有限公司 | Interface protection circuit and electronic equipment |
| CN111835069A (en) * | 2020-07-24 | 2020-10-27 | 维沃移动通信有限公司 | Charging device |
-
2018
- 2018-10-26 CN CN201811259963.8A patent/CN109038487A/en not_active Withdrawn
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110120691A (en) * | 2019-04-15 | 2019-08-13 | 出门问问信息科技有限公司 | A kind of charging base |
| CN111611130A (en) * | 2020-05-13 | 2020-09-01 | 上海龙旗科技股份有限公司 | Method, system and equipment for preventing burning of target interface |
| CN111611130B (en) * | 2020-05-13 | 2021-11-05 | 上海龙旗科技股份有限公司 | Method, system and equipment for preventing burning of target interface |
| CN111614138A (en) * | 2020-05-25 | 2020-09-01 | 维沃移动通信有限公司 | Interface protection circuit and electronic equipment |
| CN111835069A (en) * | 2020-07-24 | 2020-10-27 | 维沃移动通信有限公司 | Charging device |
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Application publication date: 20181218 |