CN202383233U - Diagnosis circuit for low-voltage differential signal cable of automobile - Google Patents
Diagnosis circuit for low-voltage differential signal cable of automobile Download PDFInfo
- Publication number
- CN202383233U CN202383233U CN2011205662397U CN201120566239U CN202383233U CN 202383233 U CN202383233 U CN 202383233U CN 2011205662397 U CN2011205662397 U CN 2011205662397U CN 201120566239 U CN201120566239 U CN 201120566239U CN 202383233 U CN202383233 U CN 202383233U
- Authority
- CN
- China
- Prior art keywords
- differential signal
- voltage differential
- low voltage
- resistance
- lvds
- 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.)
- Expired - Lifetime
Links
Images
Landscapes
- Dc Digital Transmission (AREA)
Abstract
The utility model provides a diagnosis circuit for a low-voltage differential signal cable of an automobile. The diagnosis circuit comprises an LVDS (low voltage differential signaling) encoder, an LVDS decoder, a first resistor, a second resistor, a pull-down resistor network and a voltage detector, wherein an output end of the LVDS encoder is connected with an input end of the LVDS decoder by an LVDS cable; a first end of the first resistor is connected with a power supply and a second end of the first resistor is connected with a normal phase output end of the LVDS encoder by a third resistor; a first end of the second resistor is connected with the power supply and a second end of the second resistor is connected with a negative phase output end of the LVDS encoder by a fourth resistor; the pull-down resistor network is used for pulling down and ground the normal phase input end and the negative phase input end of the LVDS encoder; and the voltage detector is connected with the second end of the first resistor and the second end of the second resistor. Due to the diagnosis circuit, the LVDS cable fault can be timely detected out.
Description
Technical field
The utility model relates to mobile unit, relates in particular to a kind of diagnostic circuit of automobile Low Voltage Differential Signal cable.
Background technology
Along with the high speed development of mobile unit, its performance receives more and more users' concern.Often include Low Voltage Differential Signal (LVDS, Low-Voltage Differential Signaling) cable in the mobile unit, for example connect the LVDS cable of main frame and display screen.LVDS cable unusual will cause the forfeiture of corresponding function, influence the use or even the traffic safety of mobile unit.
The utility model content
The technical matters that the utility model will solve provides a kind of diagnostic circuit of automobile Low Voltage Differential Signal cable, can in time find the LVDS cable fault.
For solving the problems of the technologies described above, the utility model provides a kind of diagnostic circuit of automobile Low Voltage Differential Signal cable, comprising:
Low Voltage Differential Signal scrambler and Low Voltage Differential Signal demoder, the output terminal of said Low Voltage Differential Signal scrambler is connected through the Low Voltage Differential Signal cable with the input end of said Low Voltage Differential Signal demoder;
First resistance, its first end is connected to power supply, and second end is connected to the positive output end of said Low Voltage Differential Signal scrambler through the 3rd resistance;
Second resistance, its first end is connected to power supply, and second end is connected to the negative sense output terminal of said Low Voltage Differential Signal scrambler through the 4th resistance;
The pull down resistor network is with the normal phase input end and the drop-down ground connection of negative input of said Low Voltage Differential Signal demoder;
Voltage-level detector is connected to second end of said first resistance and second end of second resistance.
Alternatively, said Low Voltage Differential Signal scrambler, voltage-level detector, first resistance, second resistance, the 3rd resistance and the 4th resistance are integrated in the main frame of mobile unit; Said Low Voltage Differential Signal demoder and pull down resistor network integration are in the display screen of said mobile unit.
Alternatively, said voltage-level detector is the microcontroller that is integrated in the said main frame, and second end of said first resistance and second end of second resistance are connected to the analog to digital conversion port of said microcontroller.
Alternatively, said pull down resistor network comprises:
The 5th resistance, its first end connects the normal phase input end of said Low Voltage Differential Signal demoder, the second end ground connection;
The 6th resistance, its first end connects the negative-phase input of said Low Voltage Differential Signal demoder, the second end ground connection.
Alternatively; The positive output end of said Low Voltage Differential Signal scrambler is connected with said Low Voltage Differential Signal cable with second electric capacity through first electric capacity respectively with the negative output terminal; Said the 3rd resistance is connected to the link of said first electric capacity and said Low Voltage Differential Signal cable, and said the 4th resistance is connected to the link of said second electric capacity and said Low Voltage Differential Signal cable.
Alternatively; The normal phase input end of said Low Voltage Differential Signal demoder is connected with said Low Voltage Differential Signal cable with the 4th electric capacity through the 3rd electric capacity respectively with negative-phase input, and said pull down resistor network is connected to the link of said the 3rd electric capacity and said Low Voltage Differential Signal cable and the link of said the 4th electric capacity and said Low Voltage Differential Signal cable.
Compared with prior art, the utlity model has following advantage:
In the diagnostic circuit of the automobile Low Voltage Differential Signal cable of the utility model embodiment; Through first resistance, the 3rd resistance the positive terminal of Low Voltage Differential Signal scrambler is pulled to power supply; Through second resistance, the 4th resistance the negative phase end of Low Voltage Differential Signal scrambler is pulled to power supply; And adopt the pull down resistor network that the normal phase input end and the negative-phase input of Low Voltage Differential Signal demoder are pulled down to ground connection; The working voltage detecting device is measured the voltage at first resistance and the second resistance place, judges the LVDS cable current states according to the magnitude of voltage that measures, and can in time find the LVDS cable fault.
Description of drawings
Fig. 1 is the circuit structure diagram of diagnostic circuit of the automobile Low Voltage Differential Signal cable of the utility model embodiment.
Embodiment
The mobile unit of prior art can't in time be found the LVDS cable fault, may influence user's normal use even cause traffic safety hidden danger.
In the diagnostic circuit of the automobile Low Voltage Differential Signal cable of the utility model embodiment; Through first resistance, the 3rd resistance the positive terminal of Low Voltage Differential Signal scrambler is pulled to power supply; Through second resistance, the 4th resistance the negative phase end of Low Voltage Differential Signal scrambler is pulled to power supply; And adopt the pull down resistor network that the normal phase input end and the negative-phase input of Low Voltage Differential Signal demoder are pulled down to ground connection; The working voltage detecting device is measured the voltage at first resistance and the second resistance place, judges the LVDS cable current states according to the magnitude of voltage that measures, and can in time find the LVDS cable fault.
Below in conjunction with specific embodiment and accompanying drawing the utility model is described further, but should limit the protection domain of the utility model with this.
Fig. 1 shows the circuit structure diagram of diagnostic circuit of the automobile Low Voltage Differential Signal cable of present embodiment; Comprise: LVDS scrambler 111 and LVDS demoder 121, the output terminal of LVDS scrambler 111 is connected through LVDS cable 13 with the input end of LVDS demoder 121; First resistance R 1, its first end is connected to power supply VCC, and second end is connected to the positive output end of LVDS scrambler through the 3rd resistance R 3; Second resistance R 2, its first end is connected to power supply VCC, and second end is connected to the negative sense output terminal of LVDS scrambler through the 4th resistance R 4; The pull down resistor network is with the normal phase input end and the drop-down ground connection GND of negative input of LVDS demoder 121; Voltage-level detector 112 is connected to the second end DET1 (i.e. the link of first resistance R 1 and the 3rd resistance R 3) of first resistance R 1 and the second end DET2 (i.e. second end of second resistance R 2 and the 4th resistance R 4) of second resistance R 2.
In the present embodiment; LVDS scrambler 111, voltage detection unit 112, first resistance R 1, second resistance R 2, the 3rd resistance R 3 and the 4th resistance R 4 specifically are to be integrated in the main frame 11 of mobile unit, and LVDS demoder 121 and pull down resistor network are to be integrated in the display screen 12 of mobile unit.
Wherein, Voltage detection unit 112 can adopt the microcontroller (MCU) in the mobile unit main frame to realize; Particularly; Second end DET1 of first resistance R 1 and the second end DET2 of second resistance R 2 are connected to modulus (A/D) conversion port of microcontroller, thereby can obtain current detection voltage in time.
The pull down resistor networking specifically can comprise: the 5th resistance R 5, and its first end connects the normal phase input end of LVDS demoder 121, the second end ground connection GND; The 6th resistance R 6, its first end connects the negative-phase input of LVDS demoder 121, the second end ground connection GND.
In the present embodiment, the input end of the output terminal of LVDS scrambler 111 and LVDS demoder 121 also is connected with electric capacity.Particularly; The positive output end of LVDS scrambler 111 is connected to LVDS cable 13 through first capacitor C 1; The negative output terminal of LVDS scrambler 111 is connected to LVDS cable 13 through second capacitor C 2; And the 3rd resistance R 3 specifically is to be connected on the link of first capacitor C 1 and LVDS cable 13, and the 4th resistance R 4 specifically is to be connected on the link of second capacitor C 2 and LVDS cable 13.
The normal phase input end of LVDS demoder 121 is connected to LVDS cable 13 through the 3rd capacitor C 3; The negative-phase input of LVDS demoder 121 is through the 4th capacitor C 4 connexon LVDS cables 13; The 5th resistance R 5 specifically is to be connected on the link of the 3rd capacitor C 3 and LVDS cable 13, and the 6th resistance R 6 specifically is to be connected on the link of the 4th capacitor C 4 and LVDS cable 13.
When LVDS cable 13 operate as normal, the magnitude of voltage DET1=VCC* (R3+R5)/(R1+R3+R5) at the second end DET1 place of first resistance R 1, the magnitude of voltage DET2=VCC* (R4+R6)/(R2+R4+R6) at the second end DET2 place of second resistance R 2; Wherein, VCC representes the magnitude of voltage of power supply VCC, and R1 representes the resistance value of first resistance R 1, and R2 representes the resistance value of second resistance R 2; R3 representes the resistance value of the 3rd resistance R 3; R4 representes the resistance value of the 4th resistance R 4, and R5 representes the resistance value of the 5th resistance R 5, and R6 representes the resistance value of the 6th resistance R 6; When LVDS cable 13 opened circuit, the magnitude of voltage of DET1 and DET2 all was supply voltage VCC; When LVDS cable 13 shorted to earths, DET1=VCC*R3/ (R1+R3), DET2=VCC*R4/ (R2+R4).Therefore, voltage-level detector 112 can judge in time the LVDS cable 13 current faults that whether taken place according to detected magnitude of voltage.
Need to prove; Above-mentioned first resistance R of mentioning 1, second resistance R 2, the 3rd resistance R 3, the 4th resistance R 4, the 5th resistance R 5, the 6th resistance R 6 can be resistance devices physically, also can be made up of through various connected modes a plurality of resistance devices physically.
Though the utility model with preferred embodiment openly as above; But it is not to be used for limiting the utility model; Any those skilled in the art are in spirit that does not break away from the utility model and scope; Can make possible change and modification, so the protection domain of the utility model should be as the criterion with the scope that the utility model claim is defined.
Claims (6)
1. the diagnostic circuit of an automobile Low Voltage Differential Signal cable is characterized in that, comprising:
Low Voltage Differential Signal scrambler and Low Voltage Differential Signal demoder, the output terminal of said Low Voltage Differential Signal scrambler is connected through the Low Voltage Differential Signal cable with the input end of said Low Voltage Differential Signal demoder;
First resistance, its first end is connected to power supply, and second end is connected to the positive output end of said Low Voltage Differential Signal scrambler through the 3rd resistance;
Second resistance, its first end is connected to power supply, and second end is connected to the negative sense output terminal of said Low Voltage Differential Signal scrambler through the 4th resistance;
The pull down resistor network is with the normal phase input end and the drop-down ground connection of negative input of said Low Voltage Differential Signal demoder;
Voltage-level detector is connected to second end of said first resistance and second end of second resistance.
2. the diagnostic circuit of automobile Low Voltage Differential Signal cable according to claim 1; It is characterized in that said Low Voltage Differential Signal scrambler, voltage-level detector, first resistance, second resistance, the 3rd resistance and the 4th resistance are integrated in the main frame of mobile unit; Said Low Voltage Differential Signal demoder and pull down resistor network integration are in the display screen of said mobile unit.
3. the diagnostic circuit of automobile Low Voltage Differential Signal cable according to claim 2; It is characterized in that; Said voltage-level detector is the microcontroller that is integrated in the said main frame, and second end of said first resistance and second end of second resistance are connected to the analog to digital conversion port of said microcontroller.
4. according to the diagnostic circuit of each described automobile Low Voltage Differential Signal cable in the claim 1 to 3, it is characterized in that said pull down resistor network comprises:
The 5th resistance, its first end connects the normal phase input end of said Low Voltage Differential Signal demoder, the second end ground connection;
The 6th resistance, its first end connects the negative-phase input of said Low Voltage Differential Signal demoder, the second end ground connection.
5. according to the diagnostic circuit of each described automobile Low Voltage Differential Signal cable in the claim 1 to 3; It is characterized in that; The positive output end of said Low Voltage Differential Signal scrambler is connected with said Low Voltage Differential Signal cable with second electric capacity through first electric capacity respectively with the negative output terminal; Said the 3rd resistance is connected to the link of said first electric capacity and said Low Voltage Differential Signal cable, and said the 4th resistance is connected to the link of said second electric capacity and said Low Voltage Differential Signal cable.
6. according to the diagnostic circuit of each described automobile Low Voltage Differential Signal cable in the claim 1 to 3; It is characterized in that; The normal phase input end of said Low Voltage Differential Signal demoder is connected with said Low Voltage Differential Signal cable with the 4th electric capacity through the 3rd electric capacity respectively with negative-phase input, and said pull down resistor network is connected to the link of said the 3rd electric capacity and said Low Voltage Differential Signal cable and the link of said the 4th electric capacity and said Low Voltage Differential Signal cable.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011205662397U CN202383233U (en) | 2011-12-29 | 2011-12-29 | Diagnosis circuit for low-voltage differential signal cable of automobile |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011205662397U CN202383233U (en) | 2011-12-29 | 2011-12-29 | Diagnosis circuit for low-voltage differential signal cable of automobile |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202383233U true CN202383233U (en) | 2012-08-15 |
Family
ID=46631726
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011205662397U Expired - Lifetime CN202383233U (en) | 2011-12-29 | 2011-12-29 | Diagnosis circuit for low-voltage differential signal cable of automobile |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202383233U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103280206A (en) * | 2013-04-27 | 2013-09-04 | 惠州市德赛西威汽车电子有限公司 | Method for monitoring vehicle-mounted LVDS (Low Voltage Differential Signaling) link |
| CN104793099A (en) * | 2015-05-08 | 2015-07-22 | 武汉精测电子技术股份有限公司 | LVDS (low-voltage differential signaling) open-circuit and short-circuit detection device and detection method |
| CN111489671A (en) * | 2019-01-28 | 2020-08-04 | 厦门雅迅网络股份有限公司 | Self-checking circuit for vehicle-mounted L VDS signal output |
-
2011
- 2011-12-29 CN CN2011205662397U patent/CN202383233U/en not_active Expired - Lifetime
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103280206A (en) * | 2013-04-27 | 2013-09-04 | 惠州市德赛西威汽车电子有限公司 | Method for monitoring vehicle-mounted LVDS (Low Voltage Differential Signaling) link |
| CN103280206B (en) * | 2013-04-27 | 2015-10-14 | 惠州市德赛西威汽车电子股份有限公司 | A kind of vehicle-mounted LVDS link monitoring method |
| CN104793099A (en) * | 2015-05-08 | 2015-07-22 | 武汉精测电子技术股份有限公司 | LVDS (low-voltage differential signaling) open-circuit and short-circuit detection device and detection method |
| CN111489671A (en) * | 2019-01-28 | 2020-08-04 | 厦门雅迅网络股份有限公司 | Self-checking circuit for vehicle-mounted L VDS signal output |
| CN111489671B (en) * | 2019-01-28 | 2023-12-15 | 厦门雅迅网络股份有限公司 | Self-checking circuit for vehicle-mounted LVDS signal output |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103063979B (en) | Load open-circuit detection circuit | |
| CN202383233U (en) | Diagnosis circuit for low-voltage differential signal cable of automobile | |
| CN203025322U (en) | Detecting device of direct-current feeder switch | |
| CN203657820U (en) | Conditioning circuit for output signals of incremental encoder | |
| CN103048584A (en) | Wire-break detecting circuit for incremental encoder | |
| CN103795027A (en) | Electric leakage detection protection circuit | |
| CN206727631U (en) | A kind of MBUS Host Protections circuit | |
| CN106130537A (en) | A kind of 1OO2D functional safety digital quantity output circuit | |
| CN201771740U (en) | Fan and fault detection circuit thereof | |
| CN202797865U (en) | Short circuit protector of M-BUS communication bus | |
| CN212781164U (en) | Circuit and system capable of simultaneously detecting grounding condition and reverse connection of zero line and live line | |
| CN201479113U (en) | Trigger interface circuit irrespective of polarity | |
| CN201716718U (en) | Single-chip microcomputer detection circuit and device thereof | |
| CN206805994U (en) | Recording instrument without paper with backlight drive protection | |
| CN202275122U (en) | Universal type detector of zinc oxide arrester | |
| CN207780108U (en) | Field-effect tube overcurrent and power supply undervoltage detection circuit | |
| CN208046223U (en) | DC power supply and its output protection circuit | |
| CN202166688U (en) | Overvoltage acquisition circuit | |
| CN206272139U (en) | A kind of electronic type of distribution terminal it is anti-jump and point, combined floodgate monitoring arrangement | |
| CN105403756A (en) | Circuit device having ground wire live detection function | |
| CN201425519Y (en) | Infrared sensing circuit | |
| CN201859195U (en) | Load condition detecting structure | |
| CN202395987U (en) | Diagnosis circuit for microphone | |
| CN204719123U (en) | A kind of overvoltage undervoltage detection circuit | |
| CN202815128U (en) | Communication line fault detection system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term |
Granted publication date: 20120815 |
|
| CX01 | Expiry of patent term |