CN208955345U - A kind of USB interface with overheat protector - Google Patents
A kind of USB interface with overheat protector Download PDFInfo
- Publication number
- CN208955345U CN208955345U CN201821674172.7U CN201821674172U CN208955345U CN 208955345 U CN208955345 U CN 208955345U CN 201821674172 U CN201821674172 U CN 201821674172U CN 208955345 U CN208955345 U CN 208955345U
- Authority
- CN
- China
- Prior art keywords
- connect
- usb interface
- resistor
- input terminal
- npn triode
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Abstract
The utility model discloses a kind of USB interfaces with overheat protector, thermal-shutdown circuit is provided at USB interface, thermal-shutdown circuit includes signal acquisition unit and signaling control unit, first resistor one end is connect with power supply, the first resistor other end and the thermistor series voltage comparator non-inverting input terminal and first resistor, the common end of thermistor connects, voltage comparator output end is connect with NPN transistor base, NPN triode emitter ground connection, NPN triode collector is connect with PNP triode base stage, PNP triode collector connects NPN transistor base, NPN triode collector is connect with processor, the charging circuit input terminal for the electronic equipment that processor is connect with USB interface connects.The utility model has the beneficial effects that the circuit is simple, stability is high, if USB interface is once occur excess temperature failure, NPN triode constant conduction, processor persistently exports low level to charging circuit, ends NMOS tube, protects electronic equipment and its load.
Description
Technical field
The utility model belongs to USB interface protection technique field, and in particular to a kind of USB interface with overheat protector.
Background technique
USB is English Universal Serial Bus(universal serial bus) abbreviation, be an external bus mark
Standard, for being connected and communicate with for specification computer and external equipment.It is mainly used in the interfacing in the field PC, USB interface is supported
The plug and play and warm connection function of equipment.
The electronic equipments such as current each mobile terminal, such as mobile phone, the digital products such as plate are both provided with USB charging function
Energy.However charger brand on the market and many kinds of, quality is irregular.As battery of mobile terminal capacity constantly increases
Add, in order to not influence user experience, the output electric current of charger is constantly enhanced, from initial several hundred milliamperes by now 3 peace
Even 5 amperes of training, during large current charge, the safety problem that USB interface is burned out since temperature is excessively high is annoying always
Mobile terminal manufacturer, i.e., it is excessively high to occur USB interface temperature during the charging process, and USB is easily caused to damage or burn out.
Utility model content
To overcome technological deficiency of the existing technology, the utility model discloses the circuit is simple, security performance is high, protects
It protects USB interface excess temperature and influences other circuits.
Technical solution adopted by the utility model to solve its technical problems is a kind of USB interface with overheat protector,
Thermal-shutdown circuit is provided at the USB interface, the thermal-shutdown circuit includes that signal acquisition unit and signal control are single
Member, the signal acquisition unit include thermistor, first resistor and voltage-stabiliser tube, and first resistor one end is connect with power supply,
The first resistor other end is connected with the thermistor, and the first resistor other end is also connect with regulator tube negative, voltage-stabiliser tube anode
Ground connection；
The signaling control unit includes voltage comparator, NPN triode, PNP triode and second resistance, and voltage compares
Device non-inverting input terminal is connect as signaling control unit input terminal with the common end of first resistor, thermistor, voltage comparator
The external threshold voltage of inverting input terminal, voltage comparator output end are connect with NPN transistor base, and NPN triode emitter connects
Ground, NPN triode collector are connect with PNP triode base stage, and PNP triode emitter is connect with power supply, PNP triode
Collector connects NPN transistor base, and PNP triode collector is also grounded by second resistance, NPN triode collector and place
Manage device connection, the charging circuit input terminal connection for the electronic equipment that processor is connect with USB interface.
Preferably, the charging circuit includes pond, 3rd resistor, the 4th resistance and NMOS tube to be charged, 3rd resistor one
End is connected as charging circuit input terminal and processor control, and the 3rd resistor other end is connect with NMOS tube grid, NMOS tube leakage
Pole is connect by the 4th resistance with power supply, NMOS tube source electrode ground connection.
Preferably, the thermal-shutdown circuit further includes the 5th resistance, and the 5th resistance is connected serially to power supply and electricity
It presses between comparator output terminal.
Preferably, the thermal-shutdown circuit further includes optical coupling isolator, and 1 foot of optical coupling isolator and regulator tube negative connect
It connects, 3 foot of optical coupling isolator is connect with power supply, and 4 foot of optical coupling isolator is connect with signaling control unit input terminal, light-coupled isolation
2 foot of device ground connection.
Preferably, the thermal-shutdown circuit further includes capacitor, and capacitor is connected in parallel to the both ends of the voltage-stabiliser tube.
Preferably, the model LM339 of the voltage comparator.
The beneficial effects of the utility model circuit is simple, and security performance is high, if excess temperature failure once occurs for USB interface,
NPN triode constant conduction, processor persistently export low level to charging circuit, end NMOS tube, protect electronic equipment and
It is loaded；Voltage-stabiliser tube prevents circuit breakdown, improves the safety of entire circuit；Optical coupling isolator all plays circuit buffer action,
Reduce the electrical connection interference between signal acquisition unit and signaling control unit.
Detailed description of the invention
Fig. 1 is a kind of circuit theory schematic diagram of thermal-shutdown circuit described in the utility model.
Fig. 2 is a kind of circuit theory schematic diagram of charging circuit described in the utility model.
Appended drawing reference: VCC- power supply, R1- first resistor, R2- second resistance, R3- 3rd resistor, the 4th electricity of R4-
Resistance, the 5th resistance of R5-, PTC- thermistor, D- voltage-stabiliser tube, C- capacitor, OC- optical coupling isolator, REF- threshold voltage, U1- electricity
Pressure comparator, Q1-NPN triode, Q2-PNP triode, Q3-NMOS pipe, E- battery, A1- signaling control unit output end,
A2- charging circuit input terminal.
Specific embodiment
More detailed description is done to the embodiments of the present invention below in conjunction with attached drawing and appended drawing reference, makes to be familiar with ability
The technology people in domain can implement accordingly after studying this specification carefully.It should be appreciated that specific embodiment described herein is only to solve
The utility model is released, is not used to limit the utility model.
In the description of the present invention, it should be noted that the orientation of the instructions such as term " on ", "horizontal", "inner" or
Positional relationship is to be based on the orientation or positional relationship shown in the drawings, and is merely for convenience of describing the present invention and simplifying the description,
Rather than the device or element of indication or suggestion meaning must have a particular orientation, be constructed and operated in a specific orientation, because
This should not be understood as limiting the present invention.
In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, term " is pacified
Dress ", " connection " shall be understood in a broad sense, for example, it may be being fixedly connected, may be a detachable connection, or be integrally connected；It can
To be mechanical connection, it is also possible to be electrically connected；It can be directly connected, can also can be indirectly connected through an intermediary
Connection inside two elements.For the ordinary skill in the art, above-mentioned term can be understood at this with concrete condition
Concrete meaning in utility model.
Embodiment: referring to attached drawing 1, a kind of attached USB interface with overheat protector shown in Fig. 2 is set at the USB interface
It is equipped with thermal-shutdown circuit, the thermal-shutdown circuit includes signal acquisition unit and signaling control unit, the signal acquisition
Unit includes thermistor PTC, first resistor R1 and voltage-stabiliser tube D, and the one end first resistor R1 is connect with power supply VCC, and first
The resistance R1 other end is connected with the thermistor PTC, and the first resistor R1 other end is also connect with voltage-stabiliser tube D cathode, voltage-stabiliser tube D
Plus earth；
The signaling control unit includes voltage comparator U1, NPN triode Q1, PNP triode Q2 and second resistance R2,
Common end of the voltage comparator U1 non-inverting input terminal as signaling control unit input terminal and first resistor R1, thermistor PTC
Connection, the external threshold voltage REF of voltage comparator U1 inverting input terminal, voltage comparator U1 output end and NPN triode Q1 base
Pole connection, NPN triode Q1 emitter ground connection, NPN triode Q1 collector are connect with PNP triode Q2 base stage, PNP triode
Q2 emitter is connect with power supply VCC, and PNP triode Q2 collector connects NPN triode Q1 base stage, PNP triode Q2 collection
Electrode also passes through second resistance R2 and is grounded, and NPN triode Q1 collector is connect with processor, and processor is connect with USB interface
The charging circuit input terminal A2 connection of electronic equipment.
In the present embodiment, the circuit is simple, and security performance is high, protects USB interface excess temperature and influences other circuits.
Specifically, thermistor PTC experiences the temperature at USB interface, thermistor PTC is positive temperature coefficient thermal electricity
Resistance, resistance value are increased with temperature and are increased.The partial pressure value at the both ends thermistor PTC transports to voltage comparator U1 non-inverting input terminal,
Voltage comparator U1 inverting input terminal external threshold voltage REF, threshold voltage REF characterize the excessively high minimum of USB interface temperature
Value, if the voltage value of voltage comparator U1 non-inverting input terminal is greater than threshold voltage REF, then it represents that USB interface temperature is excessively high, voltage
Comparator U1 output end exports high level to NPN triode Q1 base stage, NPN triode Q1 conducting, the drawing of NPN triode Q1 collector
Down to low level, PNP triode Q2 base stage is made to be pulled low to low level, PNP triode Q2 conducting, due to PNP triode Q2 collection
Electrode is connect with NPN triode Q1 base stage, then NPN triode Q1 persistently receives high level and makes itself to be connected, so signal controls
Unit output terminals A 1 persistently exports low level to processor, and processor receives the low electricity from signaling control unit output terminals A 1
It is flat, so that processor is exported low level to charging circuit, charging circuit power supply VCC is made to disconnect the company with electronic equipment power source
It connects, protects electronic equipment and other loads.
If the voltage value of voltage comparator U1 non-inverting input terminal is lower than threshold voltage REF, then it represents that USB interface temperature is in
In normal range (NR), voltage comparator U1 output end exports low level, and NPN triode Q1 and PNP triode Q2 are turned off, processor
Not will receive low level enable signal disconnects charging circuit, and charging circuit is connected to electronic equipment power source.
Wherein, thermal-shutdown circuit further includes capacitor C, and capacitor C is connected in parallel to the both ends of the voltage-stabiliser tube D, and capacitor C increases
The anti-interference ability of the thermal-shutdown circuit；5th resistance R5 be connected serially to power supply VCC and voltage comparator U1 output end it
Between, the driving capability of voltage comparator U1 output end can be improved in the 5th resistance R5, and voltage comparator U1 is enable normally to export height
Level, and voltage comparator U1 uses common model LM339 voltage comparator.
Preferably, the charging circuit includes pond E, 3rd resistor R3, the 4th resistance R4 and NMOS tube Q3 to be charged, third
The one end resistance R3 is connected as charging circuit input terminal A2 and processor control, the 3rd resistor R3 other end and NMOS tube Q3 grid
Connection, NMOS tube Q3 drain electrode are connect by the 4th resistance R4 with power supply VCC, NMOS tube Q3 source electrode ground connection.
Present embodiment is a kind of mode of charging circuit, and charging circuit input terminal A2 receives the enabled letter from processor
Number, under normal circumstances, charging circuit input terminal A2 is high level signal to USB interface temperature, and it is logical that NMOS tube leads Q3, power supply
VCC, battery E forming circuit, electric device battery E are charged normal；When USB interface when the temperature is excessively high, charging circuit input terminal
A2 is low level signal, and NMOS tube Q3 cut-off, power supply VCC and battery are formed into a loop without E method.4th resistance R4 is limited galvanic electricity
Resistance protects NMOS tube Q3, prevents NMOS tube Q3 breakdown.
Preferably, the thermal-shutdown circuit further includes optical coupling isolator OC, and optical coupling isolator OC1 foot and voltage-stabiliser tube D are negative
Pole connection, optical coupling isolator OC3 foot are connect with power supply VCC, and optical coupling isolator OC4 foot and signaling control unit input terminal connect
It connects, optical coupling isolator OC2 foot ground connection.
In the present embodiment, optocoupler sensor OC can be reduced to be electrically connected between signal acquisition unit and signaling control unit and be done
It disturbs.
The above content is the further descriptions made in conjunction with specific preferred embodiment to the utility model, cannot recognize
Determine specific embodiment of the present utility model to be only limited to these instructions.For the common skill of the utility model technical field
For art personnel, the other embodiments obtained in the case where not departing from the technical solution of the utility model be should be included in practical
In novel protection scope.
Claims (6)
1. a kind of USB interface with overheat protector, it is characterised in that: be provided with thermal-shutdown circuit, institute at the USB interface
Stating thermal-shutdown circuit includes signal acquisition unit and signaling control unit, and the signal acquisition unit includes thermistor
(PTC), first resistor (R1) and voltage-stabiliser tube (D), first resistor one end (R1) are connect with power supply (VCC), first resistor
(R1) other end is connected with the thermistor (PTC), and first resistor (R1) other end is also connect with voltage-stabiliser tube (D) cathode, surely
Pressure pipe (D) plus earth；
The signaling control unit includes voltage comparator (U1), NPN triode (Q1), PNP triode (Q2) and second resistance
(R2), voltage comparator (U1) non-inverting input terminal is as signaling control unit input terminal and first resistor (R1), thermistor
(PTC) common end connection, the external threshold voltage of voltage comparator (U1) inverting input terminal (REF), voltage comparator (U1) are defeated
Outlet is connect with NPN triode (Q1) base stage, NPN triode (Q1) emitter ground connection, NPN triode (Q1) collector and PNP
The connection of triode (Q2) base stage, PNP triode (Q2) emitter are connect with power supply (VCC), PNP triode (Q2) collector
NPN triode (Q1) base stage is connected, PNP triode (Q2) collector also passes through second resistance (R2) ground connection, NPN triode (Q1)
Collector is connect with processor, charging circuit input terminal (A2) connection for the electronic equipment that processor is connect with USB interface.
2. as described in claim 1 with the USB interface of overheat protector, it is characterised in that: the charging circuit includes wait fill
Battery (E), 3rd resistor (R3), the 4th resistance (R4) and NMOS tube (Q3), the one end 3rd resistor (R3) are defeated as charging circuit
Enter end (A2) and processor control connects, 3rd resistor (R3) other end is connect with NMOS tube (Q3) grid, NMOS tube (Q3) leakage
Pole is connect by the 4th resistance (R4) with power supply (VCC), NMOS tube (Q3) source electrode ground connection.
3. as described in claim 1 with the USB interface of overheat protector, it is characterised in that: the thermal-shutdown circuit also wraps
The 5th resistance (R5) is included, the 5th resistance (R5) is connected serially between power supply (VCC) and voltage comparator (U1) output end.
4. as described in claim 1 with the USB interface of overheat protector, it is characterised in that: the thermal-shutdown circuit also wraps
It includes optical coupling isolator (OC), 1 foot of optical coupling isolator (OC) is connect with voltage-stabiliser tube (D) cathode, 3 foot of optical coupling isolator (OC) and power supply
Power supply (VCC) connection, 4 foot of optical coupling isolator (OC) are connect with signaling control unit input terminal, and 2 foot of optical coupling isolator (OC) connects
Ground.
5. as described in claim 1 with the USB interface of overheat protector, it is characterised in that: the thermal-shutdown circuit also wraps
It includes capacitor (C), capacitor (C) is connected in parallel to the both ends of the voltage-stabiliser tube (D).
6. as described in claim 1 with the USB interface of overheat protector, it is characterised in that: the voltage comparator (U1)
Model LM339.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201821674172.7U CN208955345U (en) | 2018-10-16 | 2018-10-16 | A kind of USB interface with overheat protector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201821674172.7U CN208955345U (en) | 2018-10-16 | 2018-10-16 | A kind of USB interface with overheat protector |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN208955345U true CN208955345U (en) | 2019-06-07 |
Family
ID=66741615
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201821674172.7U Active CN208955345U (en) | 2018-10-16 | 2018-10-16 | A kind of USB interface with overheat protector |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN208955345U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113949129A (en) * | 2021-10-20 | 2022-01-18 | 安徽淘云科技股份有限公司 | Charging interface protection device of electronic equipment and electronic equipment |
-
2018
- 2018-10-16 CN CN201821674172.7U patent/CN208955345U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113949129A (en) * | 2021-10-20 | 2022-01-18 | 安徽淘云科技股份有限公司 | Charging interface protection device of electronic equipment and electronic equipment |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105322397B (en) | USB port connector and its implementation with charging protection function | |
| CN101373893B (en) | Over temperature protection circuit for battery | |
| US7924019B2 (en) | System and method for fault isolation and leakage current detection | |
| CN207200350U (en) | A kind of excess temperature overvoltage crowbar and intelligent terminal | |
| CN103545889A (en) | USB charging system, charger, mobile terminal and charging control method | |
| CN209880993U (en) | Electric connecting device | |
| CN208955345U (en) | A kind of USB interface with overheat protector | |
| CN111835074A (en) | Multi-output charging head | |
| CN217307255U (en) | Over-temperature protection circuit and switching power supply circuit | |
| CN203859538U (en) | Charging protection circuit and bluetooth loudspeaker box | |
| CN110120691A (en) | A kind of charging base | |
| CN216564541U (en) | Lightning joint and data line based on integrated overvoltage protection chip | |
| CN109391010A (en) | A kind of lithium battery high temperature automatic protection plate | |
| CN212811309U (en) | Automatic power-off protection circuit and charging protection data line | |
| CN208955692U (en) | It is a kind of with the USB interface for overcharging protection | |
| CN212965358U (en) | Broken line detection circuit with load access automatic wake-up function and power bank | |
| CN112060942A (en) | Prevent regularly charging system of electric motor car charging mouth short circuit | |
| CN101640404A (en) | Mobile phone charging protection circuit | |
| CN111509504A (en) | Method for improving data line protection function | |
| CN110416849A (en) | A kind of data line with temperature overheat protector function | |
| CN209151164U (en) | A kind of bluetooth equipment | |
| CN219394443U (en) | Charging protection circuit and electric equipment | |
| CN205536569U (en) | Fragmentary live wire of water heater detects auto -change over device | |
| CN219304507U (en) | Simplified anti-misoperation circuit | |
| CN214041535U (en) | Effective isolation voltage detection circuit in voltage range |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |