CN220382759U - Surge protection circuit of low-cost vehicle-mounted power supply and signal line - Google Patents
Surge protection circuit of low-cost vehicle-mounted power supply and signal line Download PDFInfo
- Publication number
- CN220382759U CN220382759U CN202320576009.1U CN202320576009U CN220382759U CN 220382759 U CN220382759 U CN 220382759U CN 202320576009 U CN202320576009 U CN 202320576009U CN 220382759 U CN220382759 U CN 220382759U
- Authority
- CN
- China
- Prior art keywords
- power supply
- surge
- surge protection
- capacitor
- protection
- 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
- 239000003990 capacitor Substances 0.000 claims description 49
- 230000001052 transient effect Effects 0.000 abstract description 8
- 230000001629 suppression Effects 0.000 description 26
- 238000010521 absorption reaction Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 5
- 238000011084 recovery Methods 0.000 description 3
- 238000001914 filtration Methods 0.000 description 2
- 230000001939 inductive effect Effects 0.000 description 2
- 230000003071 parasitic effect Effects 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 206010063385 Intellectualisation Diseases 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000002146 bilateral effect Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 239000003985 ceramic capacitor Substances 0.000 description 1
- 230000000593 degrading effect Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- APTZNLHMIGJTEW-UHFFFAOYSA-N pyraflufen-ethyl Chemical compound C1=C(Cl)C(OCC(=O)OCC)=CC(C=2C(=C(OC(F)F)N(C)N=2)Cl)=C1F APTZNLHMIGJTEW-UHFFFAOYSA-N 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The utility model discloses a low-cost vehicle-mounted power supply surge protection circuit which is connected between a vehicle-mounted power supply and a rear-end load by adopting a TVS (transient voltage suppressor) tube, so that the surge protection function is realized, and the protection of the rear-end load is improved. The utility model also discloses a low-cost signal line surge protection circuit, which is connected between the microcontroller and the in-vehicle CAN bus by adopting TSS, thereby realizing the surge protection function and improving the protection of the rear-end load. The technical scheme adopts the TVS or TSS with surge protection to carry out surge protection, and has the advantages of simple circuit, low cost, strong protection capability and the like.
Description
Technical Field
The utility model belongs to the technical field of Internet of vehicles, and particularly relates to a surge protection circuit of a low-cost vehicle-mounted power supply and a signal line.
Background
With the continuous development of automobile intellectualization, more and more electronic devices on the automobile are provided with an entertainment multimedia host, an automobile body control terminal, a remote control terminal, 360-degree looking around and the like. The need to protect the interfaces of these electronic devices, surging is one of the common phenomena that cause damage to the electronic device components. The surge phenomenon in automotive circuits mainly comes from two sources: firstly, strong lightning surge is formed from external environment such as strong lightning weather; the other is an inductive load from the inside of the car, such as a motor, a relay, etc. The switching on and off of the inductive load will inevitably generate a larger overvoltage in the circuit, and the value of the induced voltage often reaches several times of the power supply voltage, which causes damage to the electronic components. The surge in the circuit is transmitted to the electronic device through the wire harness, resulting in damage to the components, and serious possibility of causing short circuit of the line, causing fire.
Fig. 3 is a diagram of a conventional power protection circuit, and chinese patent application No. 202222453747.5 discloses a power protection circuit for a motion control board card, wherein an input end of the power protection circuit is connected to a power supply, an output end of the power protection circuit is connected to a post-stage circuit, and the power protection circuit comprises an input surge protection module, a high-frequency interference signal suppression module, a surge interference signal suppression module, a filter module and a post-stage circuit protection module which are sequentially connected;
the input surge protection module is connected with the power supply and the surge interference signal suppression module, and is used for absorbing abnormal surge signals in initial power supply signals received from the power supply to obtain first power supply signals and transmitting the first power supply signals to the high-frequency interference signal suppression module;
the high-frequency interference signal suppression module is connected with the input surge protection module and the surge interference signal suppression module, and is used for absorbing the high-frequency interference signal in the first power supply signal received from the input surge protection module, obtaining a second power supply signal and transmitting the second power supply signal to the surge interference signal suppression module;
the surge interference signal suppression module is connected with the high-frequency interference signal suppression module and the filter module, and is used for absorbing the surge interference signal in the second power supply signal received from the high-frequency interference signal suppression module to obtain a third power supply signal and transmitting the third power supply signal to the filter module;
the filter module is connected with the surge interference signal suppression module and the rear-stage circuit protection module, and is used for filtering transient current in the third power supply signal received from the surge interference signal suppression module, obtaining a fourth power supply signal and transmitting the fourth power supply signal to the rear-stage circuit protection module;
the rear-stage circuit protection module is connected with the filter module and the rear-stage circuit and is used for absorbing the differential mode interference signals received from the filter module to obtain a fifth power supply signal and transmitting the fifth power supply signal to the rear-stage circuit.
The input surge protection module comprises a common mode surge interference signal absorption module and a differential mode surge interference signal absorption module; the common mode surge interference signal absorption module comprises a TVS tube D1 and a TVS tube D3; the differential mode surge interference signal absorption module comprises a TVS tube D2; one end of the IVS pipe D1 is lapped between the first output end of the power supply and the input end of the high-frequency interference signal suppression module, and the other end of the IVS pipe D1 is lapped between the third output end of the power supply and the input end of the high-frequency interference signal suppression module; one end of the TVS tube D2 is lapped between the first output end of the power supply and the input end of the high-frequency interference signal suppression module, and the other end of the TVS tube D2 is lapped between the second output end of the power supply and the input end of the high-frequency interference signal suppression module; one end of the TVS tube D3 is lapped between the second output end of the power supply and the input end of the high-frequency interference signal suppression module, and the other end of the TVS tube D3 is lapped between the third output end of the power supply and the input end of the high-frequency interference signal suppression module.
The high-frequency interference suppression module comprises a capacitor C4 and a capacitor C6; one end of the capacitor C6 is connected with one end of the TVS tube D2 connected with the first output end of the power supply and the input end of the surge interference signal suppression module respectively, and the other end of the capacitor C is connected with the ground; one end of the capacitor C4 is respectively connected with one end of the TVS tube D1 connected with the third output end of the power supply and one end of the TVS tube D3 connected with the third output end of the power supply, the other end is respectively connected with one end of the TVS tube D2 connected with the second output end of the power supply, one end of the TVS tube D3 connected with the second output end of the power supply and the input end of the surge interference signal suppression module.
The surge interference signal suppression module comprises a differential mode surge interference suppression signal module and a common mode surge interference signal suppression module; the differential mode surge interference signal suppression module capacitor C5 and the capacitor C7; the common mode surge interference signal suppression module comprises an inductor L1; one end of the capacitor C5 is connected with the capacitor C4, one end of the TVS tube D2 connected with the second output end of the power supply, one end of the TVS tube D3 connected with the second output end of the power supply, a third connection end of the inductor L1 and the ground end, and the other end of the capacitor C5 is connected with one end of the capacitor C6 which is not connected with the ground end, one end of the TVS tube D2 connected with the first output end of the power supply and the second connection end of the inductor L1; one end of the capacitor C7 is connected with the first connecting end of the inductor L1 and the input end of the filter module, and the other end of the capacitor C is connected with the fourth connecting end of the inductor L1 and the input end of the filter module.
The filter module comprises a capacitor C8, a capacitor C9 and an inductor L2; one end of the capacitor C8 is connected with one end of the capacitor C7 connected with the first connecting end of the inductor L1 and the input end of the inductor L3; the other end is connected with a positive end of the capacitor C7 connected with the fourth connecting end of the inductor I1; the output end of the inductor L3 at one end of the capacitor C9 and the input end of the post-stage circuit protection module are connected, and the other end of the capacitor C9 is connected with one end of the capacitor C8, which is not connected with the inductor L3, and the output end and the ground end of the post-stage circuit protection module.
The rear-stage circuit protection module comprises a TVS tube D8; one end of the TVS tube D8 is connected with one end of the capacitor C9 connected with the inductor L3, the input end of the post-stage circuit and the power supply, and the other end of the TVS tube D8 is connected with one end of the capacitor C9 not connected with the inductor L3, the ground end and the input end of the post-stage circuit.
The motion control board power supply protection circuit also comprises a self-recovery fuse F1; the input end of the self-recovery fuse F1 is connected with one end of the TVS tube D2 connected with the first output end of the power supply, the output end is connected with the second connection end of the inductor L1, one end of the capacitor C6 not connected with the ground end, and one end of the capacitor C5 connected with the second connection end of the inductor L1.
The power supply protection circuit of the motion control board card further comprises a power supply reverse connection protection module; the power supply reverse connection protection module comprises a diode D4; the input end of the diode D4 is connected with one end of the TVS tube D2 connected with the first output end of the power supply, and the output end of the diode D4 is connected with the input end of the self-recovery fuse F1.
Chinese patent application number 202210692051X discloses a RS485 interface thunderbolt surge protection circuit, including RS485 interface and RS485 chip, the circuit still includes:
the first protection device is arranged between the positive end and the negative end of the differential signal of the RS485 interface and the PE, and is used for executing first-stage lightning surge protection on the positive end and the negative end of the differential signal of the RS485 chip;
the second protection device is arranged between the positive end and the negative end of the differential signal of the RS485 interface and the positive end and the negative end of the differential signal of the RS485 chip and is used for executing second-stage lightning surge protection on the positive end and the negative end of the differential signal of the RS485 chip;
and the third protection device is arranged between the second protection device and the internal protected ground and is used for executing third-stage lightning surge protection on the positive and negative ends of the differential signal of the RS485 chip.
The first protection device is a tripolar gas discharge tube, the second protection device is a transient blocking unit, and the third protection device is a three-terminal transient diode.
The grounding end of the RS485 interface is directly connected with PE, or the grounding end of the RS485 interface is connected with PE in parallel with a 4KV1nF capacitor through a 1M resistor, wherein the 4KV1nF capacitor is used for establishing a path for passing high frequency resistance and low frequency, and the 1M resistor is used for discharging static electricity.
Traditional approaches, either as shown in the foregoing schemes, use complex protection circuit schemes, which are relatively costly; or the protection capability is weak, and the requirements cannot be met. There is thus a need for improvement in the present case.
Disclosure of Invention
The utility model aims to provide a surge protection circuit for a low-cost vehicle-mounted power supply and a signal wire, which has the advantages of simple circuit, low cost and strong protection capability.
In order to achieve the above object, the solution of the present utility model is:
the low-cost vehicle-mounted power supply surge protection circuit comprises a fuse F1, a Schottky diode D1, a TVS tube D2 and a filter capacitor C1, wherein one end of the fuse F1 is connected with the positive electrode of a vehicle-mounted power supply, the other end of the fuse F1 is connected with the positive electrode of the Schottky diode D1, the negative electrode of the Schottky diode D1 is respectively connected with the negative electrode of the TVS tube D2 and one end of the filter capacitor C1, and the negative electrode of the vehicle-mounted power supply is respectively connected with the positive electrode of the TVS tube D2 and the other end of the filter capacitor C1 and is commonly grounded; and two ends of the filter capacitor C1 are respectively used as output ends of the surge protection circuit and are connected with a rear-end load.
The low-cost signal line surge protection circuit comprises a CAN transceiver U2, a resistor R1, a resistor R2, a capacitor C2, a TSSD3 and an ESDD4, wherein an STB pin of the CAN transceiver U2 is connected with an output pin of an MCUU1, a CANH pin of the CAN transceiver U2 is respectively connected with one end of the resistor R1, one end of the TSSD3 and one end of the ESDD4, a CANL pin of the CAN transceiver U2 is respectively connected with one end of the resistor R2, the other end of the TSSD3 and the other end of the ESDD4, the other end of the resistor R1 is connected with the other end of the resistor R2 and is commonly connected with one end of the capacitor C2, and the other end of the capacitor C2 is grounded; and two ends of the ESDD4 are respectively used as output ends of the surge protection circuit and are connected with an external CAN bus.
After the scheme is adopted, the TVS (TransientVoltage Suppressors transient voltage suppressor) or TSS (thyristor Supervisors thyristor surge suppressor) with surge protection is adopted for surge protection, and the surge protection circuit has the advantages of being simple in circuit, low in cost, strong in protection capability and the like.
Drawings
FIG. 1 is a circuit diagram of the power line surge protection circuit of the present utility model;
FIG. 2 is a circuit diagram of the signal line surge protection circuit of the present utility model;
FIG. 3 is a diagram of a prior art motion control board card power protection circuit;
fig. 4 is a diagram of a lightning surge protection circuit of an existing RS485 interface.
Detailed Description
The technical scheme and beneficial effects of the present utility model will be described in detail below with reference to the accompanying drawings.
As shown in fig. 1, the utility model provides a low-cost vehicle-mounted power supply surge protection circuit which is connected between a vehicle-mounted power supply and a rear-end load to realize a surge protection function and improve the protection of the rear-end load; the surge protection circuit comprises a fuse F1, a Schottky diode D1, a TVS tube D2 and a filter capacitor C1, wherein one end of the fuse F1 is connected with the positive electrode of a vehicle-mounted power supply, the other end of the fuse F1 is connected with the positive electrode of the Schottky diode D1, the negative electrode of the Schottky diode D1 is respectively connected with the negative electrode of the TVS tube D2 and one end of the filter capacitor C1, and the negative electrode of the vehicle-mounted power supply is respectively connected with the positive electrode of the TVS tube D2 and the other end of the filter capacitor C1 and is commonly grounded; and two ends of the filter capacitor C1 are respectively used as output ends of the surge protection circuit and are connected with a rear-end load.
In this embodiment, the fuse F1 is a polymer self-restoring fuse, which is a positive temperature coefficient polymer thermistor for overcurrent protection. When the circuit works normally, the resistance value is very small, when the circuit is over-current, the temperature of the circuit rises, the resistance value increases rapidly by several orders of magnitude, and the current in the circuit is reduced below a safety value, so that the following circuit is protected, and the circuit automatically recovers to a low resistance value after the over-current disappears.
The schottky diode D1 is fabricated using a metal-semiconductor junction principle formed by metal-semiconductor contact, which is a hot carrier diode.
TVS (TransientVoltageSupmpressors transient voltage suppressor) tube D2 is an avalanche diode which is specially designed for clamping voltage and dissipating high transient surges, and has high parasitic capacitance, and is used for overvoltage and surge protection of a power supply port.
The filter capacitor C1 adopts a multilayer ceramic capacitor, and is used for power supply filtering and decoupling.
When the power supply works, the input of the vehicle-mounted power supply firstly passes through the fuse F1 and the Schottky diode D1, then passes through the TVS tube D2 which is connected in parallel and the filter capacitor C1 at the rear end, and then supplies power to the rear end load. When the power input suffers from surge interference, a surge signal passes through the fuse F1 and the Schottky diode D1 to trigger the TVS tube D2 to act, the surge signal is from the TVS tube D2 to the ground to absorb the surge interference, and the voltage of the rear-end load is clamped in a safe voltage range, so that the rear-end load is protected from the surge interference.
As shown in fig. 2, the utility model provides a low-cost signal line surge protection circuit which is connected between a microcontroller U1 and an off-vehicle CAN bus to realize a surge protection function and improve the protection of a rear end load; the surge protection circuit comprises a CAN transceiver U2, a resistor R1, a resistor R2, a capacitor C2, a TSSD3 and an ESDD4, wherein an STB pin of the CAN transceiver U2 is connected with an output pin of the MCUU1, a CANH pin of the CAN transceiver U2 is respectively connected with one end of the resistor R1, one end of the TSSD3 and one end of the ESDD4, a CANL pin of the CAN transceiver U2 is respectively connected with one end of the resistor R2, the other end of the TSSD3 and the other end of the ESDD4, the other end of the resistor R1 is connected with the other end of the resistor R2 and is commonly connected with one end of the capacitor C2, and the other end of the capacitor C2 is grounded; and two ends of the ESDD4 are respectively used as output ends of the surge protection circuit and are connected with the CAN bus in the vehicle.
MCU (microcontroller Unit microcontroller) U1 adopts high-performance automobile-level microcontroller to realize management and control of each functional module in the Internet of vehicles terminal, and comprises CAN controller.
The CAN transceiver U2 adopts a high-speed CAN transceiver facing the automobile application and is used for connecting the MCU and the in-car CAN bus.
And the resistor R1 and the resistor R2 are patch resistors and are terminal matching resistors of the CAN bus.
The capacitor C2 adopts a patch capacitor, and is a terminal matching capacitor of the CAN bus.
The TSS (Thyrristor Supervisors thyristor surge suppressor) D3 has the characteristics of quick response (response time ns level), strong surge absorption capacity, bilateral symmetry, high reliability and the like. But its conduction characteristic is close to short circuit, and can not be directly used in active circuit, and because of low parasitic capacitance, it is used for protecting signal interface.
ESDD4 is a protection device that protects CAN interface circuitry from pulse, electrostatic damage, thereby failing or degrading performance.
In operation, when the CAN interfaces (CANH and CAN_L) are subjected to surge interference, the D3 (TSS) pipe is triggered to act, and a surge signal flows out of the CAN_L from the CAN_H through the D3 (TSS). The surge interference is absorbed, and the voltage of the rear-end load is clamped in a safe voltage range, so that the rear-end load is protected from the surge interference.
In summary, the TVS (transient voltage suppressors) or TSS (thyristor suppresives thyristor surge suppressors) with surge protection can be selected for surge protection, and the circuit is simple, the cost is low, and the protection capability is strong.
The above embodiments are only for illustrating the technical idea of the present utility model, and the protection scope of the present utility model is not limited thereto, and any modification made on the basis of the technical scheme according to the technical idea of the present utility model falls within the protection scope of the present utility model.
Claims (1)
1. A low cost signal line surge protection circuit, characterized by: the capacitive touch screen comprises a CAN transceiver U2, a first resistor (R1), a second resistor (R2), a capacitor (C2), a TSS (D3) and an ESD (D4), wherein a STB pin of the CAN transceiver (U2) is connected with an output pin of the MCU (U1), a CANH pin of the CAN transceiver (U2) is respectively connected with one end of the first resistor (R1), one end of the TSS (D3) and one end of the ESD (D4), a CANL pin of the CAN transceiver (U2) is respectively connected with one end of the second resistor (R2), the other end of the TSS (D3) and the other end of the ESD (D4), the other end of the first resistor (R1) is connected with the other end of the second resistor (R2) and is commonly connected with one end of the capacitor (C2), and the other end of the capacitor (C2) is grounded; and two ends of the ESD (D4) are respectively used as output ends of the surge protection circuit and are connected with an external CAN bus.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202320576009.1U CN220382759U (en) | 2023-03-22 | 2023-03-22 | Surge protection circuit of low-cost vehicle-mounted power supply and signal line |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202320576009.1U CN220382759U (en) | 2023-03-22 | 2023-03-22 | Surge protection circuit of low-cost vehicle-mounted power supply and signal line |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220382759U true CN220382759U (en) | 2024-01-23 |
Family
ID=89568943
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202320576009.1U Active CN220382759U (en) | 2023-03-22 | 2023-03-22 | Surge protection circuit of low-cost vehicle-mounted power supply and signal line |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN220382759U (en) |
-
2023
- 2023-03-22 CN CN202320576009.1U patent/CN220382759U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103515942A (en) | Protection circuit of communication interface | |
| CN113726626B (en) | Filter protection circuit based on CAN bus driver chip | |
| CN101162840A (en) | Interface protective circuit | |
| CN220382759U (en) | Surge protection circuit of low-cost vehicle-mounted power supply and signal line | |
| CN204578080U (en) | A kind of surge protection circuit | |
| CN209282829U (en) | A kind of circuit inhibiting inrush current using thermistor | |
| CN211018264U (en) | CAN communication circuit with high anti-interference characteristic | |
| CN219513785U (en) | Surge protection device and charging system | |
| CN207388881U (en) | A kind of battery management system CAN communication circuit | |
| CN207835483U (en) | A kind of CAN interface circuit | |
| CN200994064Y (en) | Power supply protection circuit for automobile charger | |
| CN116979495A (en) | Circuit capable of optimizing withstand voltage and lightning stroke | |
| CN210258300U (en) | Input protection circuit of electronic equipment of vehicle and vehicle | |
| CN112838574A (en) | Anti-electromagnetic interference vehicle-mounted controller circuit | |
| CN110445142B (en) | Strong electromagnetic pulse multi-stage protection device with detection and display functions | |
| Lepkowski et al. | EMI/ESD solutions for the CAN network | |
| CN220139569U (en) | CAN communication protection circuit | |
| CN211043483U (en) | Hall current sampling circuit | |
| CN204314464U (en) | Peculiar to vessel, Vehicular comprehensive Beidou satellite navigation Integrated Receiver | |
| CN113904315A (en) | Method for protecting serial port of data communication gateway machine of transformer substation | |
| CN214278699U (en) | RS485 communication circuit and electrical apparatus | |
| CN219999032U (en) | Protection circuit of vehicle-mounted video port and vehicle | |
| CN217406187U (en) | Surge lightning protection filter integrated circuit based on direct current power supply | |
| CN219535631U (en) | Multistage lightning protection filter circuit | |
| CN203553929U (en) | Electrostatic protection circuit of CAN bus |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CP03 | Change of name, title or address |
Address after: Building 1, 5th Floor, No. 116 Jiangbin East Avenue, Mawei District, Fuzhou City, Fujian Province, China Patentee after: FLAIRCOMM MICROELECTRONICS, Inc. Country or region after: China Address before: Building 1, 7th Floor, No.116 Jiangbin East Avenue, Mawei District, Fuzhou City, Fujian Province, China 351000 Patentee before: FLAIRCOMM MICROELECTRONICS, Inc. Country or region before: China |
|
| CP03 | Change of name, title or address |