CN110299949A - A kind of vehicle-mounted tuning system and USB data transmission codan - Google Patents
A kind of vehicle-mounted tuning system and USB data transmission codan Download PDFInfo
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- CN110299949A CN110299949A CN201810245072.0A CN201810245072A CN110299949A CN 110299949 A CN110299949 A CN 110299949A CN 201810245072 A CN201810245072 A CN 201810245072A CN 110299949 A CN110299949 A CN 110299949A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B15/00—Suppression or limitation of noise or interference
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B15/00—Suppression or limitation of noise or interference
- H04B15/02—Reducing interference from electric apparatus by means located at or near the interfering apparatus
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- Computer Networks & Wireless Communication (AREA)
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- Emergency Protection Circuit Devices (AREA)
Abstract
The present invention relates to vehicle electric field, a kind of vehicle-mounted tuning system and USB data transmission codan are disclosed.Circuit includes: the first pressure-sensitive impedance circuit, it is connected electrically between the data-interface of USB interface and ground, when the voltage of pressure-sensitive impedance circuit is more than predetermined value, the impedance of pressure-sensitive impedance circuit changes with the non-linear to voltage at pressure-sensitive impedance circuit both ends, by the voltage clamping of pressure-sensitive impedance circuit in a scheduled constant voltage；ESD protection circuit; Data Input Interface, data output interface including the conducting of mutual circuit; surge protection circuit is provided between Data Input Interface, data output interface; surge protection circuit is used for; when the absolute value of Data Input Interface, and/or the voltage of data output interface is greater than scheduled voltage value, surge energy is released to ground.
Description
Technical field
The present invention relates to vehicle electric field, especially vehicle-mounted tuning system field discloses a kind of vehicle-mounted tuning system
And USB data transmission codan.
Background technique
There is a system to be called vehicle-mounted DSP tuning system in Market for refitting after automobile audio, vehicle-mounted DSP audio frequency apparatus passes through
USB interface connects PC tuning software and solves that former vehicle audible sound orientation problem, sound field level fuzzy, high pitch be penetrating, voice
The problems such as fuzzy not full, the thin bass of intermediate frequency is powerless, these data are all to be transferred to vehicle-mounted DSP audio by USB interface to set
It is standby to adjust former vehicle audio.
But in the electronics of Automobile Complex, power-supply system, whens USB transmission data, suffers from various different degrees of electromagnetism
Interference leads to the electronic device inside corrupted data, loss or breakdown DSP audio frequency apparatus, therefore it is simple to design a kind of structure, reliably
Property is strong, can effectively improve the stability of system, prevent the USB data transmission codan of external interference.
Summary of the invention
The first purpose of the embodiment of the present invention is to provide a kind of USB data transmission codan and with the circuit
Vehicle-mounted tuning system improves the anti-interference ability of vehicle-mounted tuning system.
In a first aspect, the embodiment of the present invention provides a kind of USB data transmission codan, characterized in that include:
First pressure-sensitive impedance circuit, is connected electrically between the data-interface of USB interface and ground, when the described first pressure-sensitive impedance
When the voltage of circuit is more than predetermined value, the impedance of the first pressure-sensitive impedance circuit is with the described first pressure-sensitive impedance circuit both ends
Non-linear to voltage variation, by the voltage clamping of the described first pressure-sensitive impedance circuit in a scheduled constant voltage；
ESD protection circuit, Data Input Interface, data output interface including the conducting of mutual circuit, wherein described
After Data Input Interface is connected electrically in the data-interface of the USB interface,
It is additionally provided with surge protection circuit between the Data Input Interface, data output interface,
The surge protection circuit is used for, absolute when the voltage of the Data Input Interface, and/or data output interface
When value is greater than scheduled voltage value, surge energy bypass is released to ground.
Optionally, further includes:
First filter circuit is connected electrically between the data-interface and ground of the USB interface.
Optionally, first filter circuit includes:
First filter capacitor, is connected electrically between the anode and ground of the data-interface；
Second filter capacitor, is connected electrically between the cathode and ground of the data-interface.
Optionally, further includes:
Third filter capacitor is connected electrically between the power interface and ground of the USB interface.
Optionally, further includes:
LC filter circuit is connected electrically in the power interface of the USB interface and the power supply of the ESD protection circuit
Between incoming end, operating voltage is provided for the ESD protection circuit.
Optionally, the described first pressure-sensitive impedance circuit includes:
First varistor is connected electrically between the anode and ground of the data-interface of the USB interface；
Second varistor is connected electrically between the cathode and ground of the data-interface of the USB interface.
Optionally, first varistor, the varistor that the second varistor is model AVRL161A3R3GTA.
Optionally, the second pressure-sensitive impedance circuit is connected electrically between the power interface and ground of the USB interface.
Optionally, the described second pressure-sensitive impedance circuit is the varistor of model AVRL161A3R3GTA.
Optionally, the surge protection circuit includes:
The surge protection circuit includes:
First surge circuit is provided with first switch circuit, second switch circuit, is respectively electrically connected to the data
Between the positive voltage data-interface and ground of input interface,
When the voltage for being input to the positive voltage data-interface is forward voltage and is greater than leading for the first switch circuit
When the pressure that is powered, the first switch circuit conducting, the energy more than or equal to the conducting voltage of the first switch circuit passes through
The first switch circuit is released to ground,
The voltage for being input to the positive voltage data-interface is negative voltage and the conducting for being greater than the second switch circuit
When voltage, the second switch circuit conducting, the energy more than or equal to the conducting voltage of the second switch circuit passes through institute
Second switch circuit is stated to release to ground；
Second surge circuit is provided with third switching circuit, the 4th switching circuit, is respectively electrically connected to the data
Between the negative voltage data interface and ground of input interface,
When the voltage for being input to the negative voltage data interface is forward voltage and the electric conduction for being greater than third switching circuit
When pressure, the third switching circuit conducting passes through described more than or equal to the energy of the conducting voltage of the third switching circuit
Third switching circuit is released to ground,
When being input to, the voltage of negative voltage data interface is negative voltage and the conducting for being greater than the 4th switching circuit
When voltage, the 4th switching circuit conducting, the energy more than or equal to the conducting voltage of the 4th switching circuit passes through institute
The 4th switching circuit is stated to release to ground.
Optionally, the ESD protection circuit selects the chip of model USBLC6-2 to realize.
Second aspect, vehicle-mounted tuning system provided in an embodiment of the present invention, comprising:
USB interface and it is connected electrically in above-mentioned any USB data transmission codan.
11, USB data transmission codan according to claim 10, characterized in that
The ESD protection circuit selects the chip of model USBLC6-2 to realize.
12, a kind of vehicle-mounted tuning system, comprising:
Any USB data transmission of USB interface and the claims 1 to 10 being connected electrically on the USB interface
Codan.
Therefore under in-vehicle electronic system environment, electrostatic has concealment in a device, potentiality, randomness, answers
Polygamy, such as step on the gas, open car light, lifting window movement all and can bring the generation and interference of electrostatic, and if in vehicle-mounted DSP
This reality is electrically connected between the USB interface of the related to USB data transmission of audio frequency apparatus product and core devices MCU (and/or DSP)
The USB data transmission codan for applying example, can effectively inhibit surge voltage and electrostatic interference, protect the core of mobile unit
Device MCU and DSP, improve the quality of data of USB transmission data, so that the interference rejection capability of mobile unit product is improved, than
Such as when current mobile unit is vehicle-mounted audio device, its sound quality can be greatly improved, reduces noise.
Detailed description of the invention
Fig. 1 is the USB data transmission codan schematic illustration that the embodiment of the present invention 1 provides；
Fig. 2 is the inside schematic illustration for the ESD protection circuit that the embodiment of the present invention 1 provides.
Specific embodiment
Below in conjunction with attached drawing and specific embodiment, the present invention will be described in detail, herein illustrative examples of the invention
And explanation is used to explain the present invention, but not as a limitation of the invention.
Embodiment 1:
It is shown in Figure 1, present embodiments provide a kind of USB data transmission interference suppression for being connected to 00 rear end of usb 1
Circuit processed, codan mainly include the first pressure-sensitive impedance circuit 101 and ESD protection circuit 102.
Wherein, the first pressure-sensitive impedance circuit 101, is connected electrically between data-interface DM, DP of USB interface and ground, works as pressure
When the voltage at quick impedance circuit both ends is more than predetermined value, the general predetermined value is set by the user, for example is set to certain big
It is small, surge (i.e. transient state input energy rises sharply, and transient voltage value becomes very big), the first pressure-sensitive impedance occurs to identify current circuit
The impedance of circuit 101 changes with the non-linear to voltage at pressure-sensitive impedance circuit both ends, by the electricity at the first pressure-sensitive impedance circuit both ends
Pressing tongs position, to carry out surge protection in the front end of ESD protection circuit 102, avoids wave in a scheduled constant voltage
Data Input Interface DP1, DM1 that energy enters ESD protection circuit 102 by data line are gushed, electrostatic discharge (ESD) protection is caused
Circuit 102 is burnt out.
ESD protection circuit 102 include circuit conducting Data Input Interface DP1, DM1, data output interface D+,
D- (i.e. by Fig. 1,2 as it can be seen that Data Input Interface DP1 is connected with data output interface D+ circuit, Data Input Interface DM1, with number
It is connected according to output interface D- circuit).
Surge protection circuit is additionally provided between Data Input Interface DM1, DP1, data output interface D+, D-, it will
Surge energy is bypassed by surge protection circuit to ground, and the working principle of the surge protection circuit is inputted when being input to data
When the absolute value of the voltage of interface is greater than scheduled voltage value, surge energy is released to ground, surge is avoided to flow to data output
Interface reduces the signal of data output interface.Generally, which is set by the user, for example is set to certain big
It is small, surge (i.e. transient state input energy rises sharply, and transient voltage value becomes very big) occurs to identify current circuit.
In practice, under in-vehicle electronic system environment, electrostatic has concealment in a device, potentiality, randomness, answers
Polygamy, such as step on the gas, open car light, lifting window movement all and can bring the generation and interference of electrostatic, and if in vehicle-mounted DSP
This reality is electrically connected between the USB interface of the related to USB data transmission of audio frequency apparatus product and core devices MCU (and/or DSP)
The USB data transmission codan for applying example, can effectively inhibit surge voltage and electrostatic interference, protect the core of mobile unit
Device MCU and DSP, improve the quality of data of USB transmission data, so that the interference rejection capability of mobile unit product is improved, than
Such as when current mobile unit is vehicle-mounted audio device, its sound quality can be greatly improved, reduces noise.
As the signal of the present embodiment, this circuit further includes the first filter circuit 103, is connected electrically in usb 1 00
Between data-interface DM, DP and ground.To carry out low-pass filtering to the electric signal accessed from usb 1 00, lowpass noise is interfered
Inhibited.
Wherein, the first above-mentioned filter circuit 103 is by being respectively electrically connected between the positive DP of data-interface and ground, being electrically connected
The first filter capacitor C1, the second filter capacitor C2 connect between the cathode DM and ground of data-interface is realized.
As the signal of the present embodiment, the present embodiment circuit, further includes: be connected electrically in the power interface of usb 1 00
Third filter capacitor C3 between VDD and ground.In the present embodiment, can from 100 power interface VDD to electrostatic discharge (ESD) protection
Circuit 102 offer+5V operating voltage Vdd, the third filter capacitor C3 are for the electricity for being input to ESD protection circuit 102
Pressure carries out low-pass filtering.
In order to further increase the working robust of ESD protection circuit 102, can with but be not limited to further set
LC filter circuit 104 is set, input terminal is connected electrically between the power interface of USB interface and ground, output end and electrostatic discharge (ESD) protection
Circuit 102 is electrically connected, and further increases the stability of the operating voltage of ESD protection circuit 102, it is ensured that circuit stability work
Make.
As the signal of the present embodiment, the pressure-sensitive impedance circuit 101 of the first of the present embodiment can be connect using USB is connected electrically in
The first varistor AVR1 between the positive DP and ground of mouthfuls 100 data-interface and the number for being connected electrically in usb 1 00
According to the second varistor AVR2 between the cathode DM and ground of interface.
Wherein, when the voltage of the first varistor AVR1, the second varistor AVR2 be greater than predetermined value when, resistance value with
The non-linear decline of the rising of voltage exists the voltage clamping at its both ends to releasing portion of energy (i.e. surge energy) to ground
On certain voltage, the transmission interference for realizing usb data inhibits.
Furthermore it is also possible to further be electrically connected the second pressure-sensitive impedance circuit of step between the power interface of USB interface and ground
105, and similarly, which can also but be not limited to realize using third varistor AVR3, from
And AF panel is carried out to the supply voltage of ESD protection circuit 102.
As the present embodiment signal rather than limit, the first varistor AVR1, the second varistor of the present embodiment
AVR2, third varistor AVR3 can be, but not limited to select respectively the varistor of model AVRL161A3R3GTA to realize.
Its specific application principle is detailed in the device introduction.
It is shown in Figure 2, as the present embodiment signal rather than limit, the surge protection circuit of the present embodiment includes:
First surge circuit is provided with first switch circuit, second switch circuit, is respectively electrically connected to data input
Between the positive voltage data-interface DM1 and ground of interface, its working principle is that:
When the voltage for being input to positive voltage data-interface DP1 is forward voltage and the electric conduction for being greater than first switch circuit
Pressure, the conducting of first switch circuit are input to the voltage value of positive voltage data-interface DP1 at or above conducting voltage at this time
Energy first switch circuit is released to ground, is realized surge energy and is released.
Wherein, referring to fig. 2, first switch circuit is realized by diode D1, at this point, first switch circuit arrives conducting voltage
For the breakdown voltage of diode D1, surge energy is released by diode D1, zener diode Dz to ground, it should be noted that
Fig. 2 is signal using diode D2 as first switch circuit, but is actually not limited to that, is such as but not limited to use
Transistor or other equivalent circuits are realized.
When the DP1 voltage for being input to positive voltage data-interface is negative voltage and the conducting voltage for being greater than second switch circuit
When, the conducting of second switch circuit is input to the voltage value of positive voltage data-interface DP1 at or above the conducting voltage at this time
Energy release to ground by second switch circuit, realize surge energy and release, for example, referring to fig. 2, second switch circuit can
To be realized by diode D4, at this point, the conducting voltage of second switch circuit is the breakdown voltage of diode D4, need to illustrate
It is that Fig. 2 is signal using diode D4 as second switch circuit, but is actually not limited to that, being such as but not limited to can be with
It is realized using transistor or other equivalent circuits；
Second surge circuit is provided with third switching circuit, the 4th switching circuit, is respectively electrically connected to data input
Between the negative voltage data interface DM1 and ground of interface, its working principle is that:
When the voltage for being input to negative voltage data interface DM1 is forward voltage and the conducting voltage for being greater than third switching circuit
When value, the conducting of third switching circuit is input to the voltage value of negative voltage data interface DM1 at or above the electric conduction at this time
The energy of pressure is released by third switching circuit to ground, is realized surge energy and is released.Wherein, referring to fig. 2, third switching circuit
It is embodied as illustrating by diode D3, at this point, the breakdown voltage for being diode D4 to conducting voltage of third switching circuit, energy warp
Cross diode D3, zener diode Dz releases surge energy to ground.It should be noted that Fig. 2 is using diode D3 as third
Switching circuit is signal, but is actually not limited to that, is such as but not limited to that transistor or other equivalent electricity can also be used
It realizes on road；
When being input to, the voltage of negative voltage data interface DM1 is negative voltage and the electric conduction for being greater than the 4th switching circuit
When pressure, the 4th switching circuit conducting, the energy for being input to negative voltage data interface DM1 at this time passes through the 4th switching circuit for voltage
Energy at or above the conducting voltage of the 4th switching circuit is released to ground, is realized surge energy and is released.Wherein, referring to
Fig. 2, the 4th switching circuit can be realized that the conducting voltage of the 4th switching circuit is the breakdown potential of diode D2 by diode D2
Pressure, surge energy is released by diode D2 to ground at this time；It should be noted that Fig. 2 is using diode D2 as the 4th switch electricity
Road, but be actually not limited to that, it is such as but not limited to realize using transistor or other equivalent circuits.
It is shown in Figure 2, in the pressure stabilizing two that the power supply incoming end electrical connection one of ESD protection circuit 102 is reversely grounded
Pole pipe Dz may insure the voltage stability of ESD protection circuit 102, improve the robustness of circuit.
As the signal of the present embodiment, the ESD protection circuit 102 of the present embodiment can select model USBLC6-
2 chip is realized.
Embodiments described above does not constitute the restriction to the technical solution protection scope.It is any in above-mentioned implementation
Made modifications, equivalent substitutions and improvements etc., should be included in the protection model of the technical solution within the spirit and principle of mode
Within enclosing.
Claims (10)
1. a kind of USB data transmission codan, characterized in that include:
First pressure-sensitive impedance circuit, is connected electrically between the data-interface of USB interface and ground, when the described first pressure-sensitive impedance circuit
Voltage when being more than predetermined value, the impedance of the first pressure-sensitive impedance circuit with the described first pressure-sensitive impedance circuit both ends voltage
Nonlinear change, by the voltage clamping of the described first pressure-sensitive impedance circuit in a scheduled constant voltage；
ESD protection circuit, Data Input Interface, data output interface including the conducting of mutual circuit, wherein the data
After input interface is connected electrically in the data-interface of the USB interface,
It is additionally provided with surge protection circuit between the Data Input Interface, data output interface,
The surge protection circuit is used for, when the absolute value of the Data Input Interface, and/or the voltage of data output interface is big
When scheduled voltage value, surge energy bypass is released to ground.
2. USB data transmission codan according to claim 1, characterized in that further include:
First filter circuit is connected electrically between the data-interface and ground of the USB interface.
3. USB data transmission codan according to claim 2, characterized in that
First filter circuit includes:
First filter capacitor, is connected electrically between the anode and ground of the data-interface；
Second filter capacitor, is connected electrically between the cathode and ground of the data-interface.
4. USB data transmission codan according to claim 1, characterized in that further include:
Third filter capacitor is connected electrically between the power interface and ground of the USB interface.
5. USB data transmission codan according to claim 1, characterized in that further include:
The confession of LC filter circuit, the power interface and the ESD protection circuit that are connected electrically in the USB interface is electrically accessed
Between end, operating voltage is provided for the ESD protection circuit.
6. USB data transmission codan according to claim 1, characterized in that
The first pressure-sensitive impedance circuit includes:
First varistor is connected electrically between the anode and ground of the data-interface of the USB interface；
Second varistor is connected electrically between the cathode and ground of the data-interface of the USB interface.
7. USB data transmission codan according to claim 6, characterized in that
The varistor that first varistor, and/or the second varistor are model AVRL161A3R3GTA.
8. USB data transmission codan according to claim 1, characterized in that further include:
Second pressure-sensitive impedance circuit, is connected electrically between the power interface and ground of the USB interface.
9. USB data transmission codan according to claim 8, characterized in that
The second pressure-sensitive impedance circuit is the varistor of model AVRL161A3R3GTA.
10. USB data transmission codan according to claim 1, characterized in that
The surge protection circuit includes:
First surge circuit is provided with first switch circuit, second switch circuit, is respectively electrically connected to the data input
Between the positive voltage data-interface and ground of interface,
When the voltage for being input to the positive voltage data-interface is forward voltage and the electric conduction for being greater than the first switch circuit
When pressure, the first switch circuit conducting passes through described more than or equal to the energy of the conducting voltage of the first switch circuit
First switch circuit is released to ground,
The voltage for being input to the positive voltage data-interface is negative voltage and the conducting voltage for being greater than the second switch circuit
When, second switch circuit conducting passes through described the more than or equal to the energy of the conducting voltage of the second switch circuit
Two switching circuits are released to ground；
Second surge circuit is provided with third switching circuit, the 4th switching circuit, is respectively electrically connected to the data input
Between the negative voltage data interface and ground of interface,
When the voltage for being input to the negative voltage data interface is forward voltage and is greater than the conducting voltage of third switching circuit,
The third switching circuit conducting, the energy more than or equal to the conducting voltage of the third switching circuit are opened by the third
Powered-down road is released to ground,
When being input to, the voltage of negative voltage data interface is negative voltage and the conducting voltage for being greater than the 4th switching circuit
When, the 4th switching circuit conducting passes through described the more than or equal to the energy of the conducting voltage of the 4th switching circuit
Four switching circuits are released to ground.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810245072.0A CN110299949A (en) | 2018-03-23 | 2018-03-23 | A kind of vehicle-mounted tuning system and USB data transmission codan |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810245072.0A CN110299949A (en) | 2018-03-23 | 2018-03-23 | A kind of vehicle-mounted tuning system and USB data transmission codan |
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| Publication Number | Publication Date |
|---|---|
| CN110299949A true CN110299949A (en) | 2019-10-01 |
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ID=68025904
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810245072.0A Pending CN110299949A (en) | 2018-03-23 | 2018-03-23 | A kind of vehicle-mounted tuning system and USB data transmission codan |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110716474A (en) * | 2019-11-07 | 2020-01-21 | 上海庆科信息技术有限公司 | Voice development kit and simulator circuit thereof |
-
2018
- 2018-03-23 CN CN201810245072.0A patent/CN110299949A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110716474A (en) * | 2019-11-07 | 2020-01-21 | 上海庆科信息技术有限公司 | Voice development kit and simulator circuit thereof |
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Application publication date: 20191001 |
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