CN101266587A - USB equipment detection circuit - Google Patents
USB equipment detection circuit Download PDFInfo
- Publication number
- CN101266587A CN101266587A CNA2008100276497A CN200810027649A CN101266587A CN 101266587 A CN101266587 A CN 101266587A CN A2008100276497 A CNA2008100276497 A CN A2008100276497A CN 200810027649 A CN200810027649 A CN 200810027649A CN 101266587 A CN101266587 A CN 101266587A
- Authority
- CN
- China
- Prior art keywords
- usb device
- schottky diode
- comparer
- interface
- circuit
- 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.)
- Granted
Links
Images
Abstract
The invention discloses an USB device detection circuit, which includes an interface J1 connected to the USB device, a schottky diode D1 is connected to the power foot of the interface J1, the schottky diode D1 can adjust a comparison circuit connection for voltage variation of the each end of the diode D1, the comparison circuit is connected to a control chip through a signal amplification circuit. The invention chooses the schottky diode which has low power dissipation and shortest reverse recovery time as a detection method, the schottky diode rapidly reacts to the voltage variation of the power foot of the interface, then the USB device is quickly identified whether to access or not. Furthermore, high-current power supply is provided to the USB device for choosing the schottky diode. The invention has the characteristics of low cost, strong identification ability and strong compatibility.
Description
Technical field
The present invention relates to the technical field whether a kind of checkout equipment inserts, be specifically related to a kind of USB device and insert the circuit that detects.
Background technology
Along with popularizing of USB device (USB flash disk, MP3, MP4 and portable hard drive etc.) with popular, except computer product, increasing electronic product also provides USB interface, as TV, DVD, mobile phone etc., has the fast and convenience operation of speed by USB interface storage or transmission data information etc.In order to increase the recreational of automobile, vehicle-mounted stereo sets such as increasing vehicle-mounted radio reception, vehicle-mounted CD, vehicle-carrying DVD have also been set up USB interface.Because USB device is of a great variety, whether be inserted on the interface, prior art adopts following two kinds of technological means in order in time to judge or to detect USB device:
1, detects by signal pins, promptly by the D+ input on the USB.D+ signal pins when inserting USB device on the USB flash disk produces a high level, just can judge that by this high level CPU whether USB flash disk is at the insertion state.The shortcoming of the method is that dissimilar USB flash disks and other USB device are arranged on the market, and the equipment that has can produce high level in the D+ signal pins, and what have is just not all right, and there is compatible problem in this method.
2, detect by professional current detecting IC.The USB flash disk power pin produces electric current when USB flash disk inserts, and seals in milliohm level resistance in the USB power pin and comes comparison by precision comparator again.The change in voltage of comparer when inserting U equipment and not inserting U equipment judged.The shortcoming of this method is to insert accurate small resistor and precision comparator, and price is very high.
Summary of the invention
The technical matters that the present invention need solve provides that a kind of cost is low, recognition capability is strong, the compatible USB device testing circuit of all USB device at present.
Designed a kind of USB device testing circuit according to above-mentioned purpose, comprise the interface J1 that is connected with USB device, on the supply pin of interface J1, be connected with schottky diode D1, this schottky diode D1 is connected with judging the comparator circuit that diode D1 both end voltage changes, and comparator circuit connects with control chip by signal amplification circuit.
Described comparator circuit comprises comparer U1A and peripheral circuit thereof, the positive input terminal of comparer U1A is connected with the negative electrode of schottky diode D1 and the supply pin of interface J1, the negative input end of comparer U1A is connected with the anode of schottky diode D1 by resistance R 5, and the output terminal of comparer U1A is connected with the startup amplifying circuit.
Described signal amplification circuit comprises triode Q1, resistance R 1, R2, R8, and the output terminal of comparer U1A is connected with the base stage of triode Q1 through resistance R 2, R3, and the collector of Q1 is connected with control chip through the USB_DET end.
The present invention has the following advantages:
1, the present invention has selected for use the schottky diode of extremely lacking low-power consumption, reverse recovery time as the means that detect, the schottky diode change in voltage of docking port supply pin is fast promptly reacted, thereby the access that can recognize USB device soon whether.In addition, owing to selected for use schottky diode to provide big electric current power supply for USB device.
2, can detect various little electric currents and big electric current USB device.
3, can not produce big pressure reduction exerts an influence to USB device.
4, low price, zero device is purchased easily.
Description of drawings
Fig. 1 is circuit theory diagrams of the present invention.
Embodiment
For the ease of those skilled in the art's understanding, principle of work of the present invention is described in further detail below in conjunction with specific embodiment and accompanying drawing:
As shown in Figure 1, a kind of USB device testing circuit, this USB device testing circuit can be applied in the vehicle-mounted stereo sets such as vehicle-mounted radio reception, vehicle-mounted CD, vehicle-carrying DVD, USB device is connected with the said equipment by interface J1, the supply pin of interface J1 (USB_VCC) is connected with+12V power supply by resistance R 9, and supply pin (USB_VCC) also is connected with the comparator circuit end with the negative electrode of schottky diode D1.Described comparator circuit comprises comparer U1A, resistance R 2, R4, R5, R6, R7, the positive input terminal of comparer U1A (3 pin) is connected with the negative electrode of schottky diode D1 by resistance R 6, resistance R 7 is connected between the positive input terminal and ground of comparer U1A, the anode of D1 is connected with power supply+5.3V and is connected with the negative input end (2 pin) of comparer U1A and an end of resistance R 4 by resistance R 5, resistance R 4 other end ground connection, the output terminal of comparer U1A is connected with signal amplification circuit by resistance R 2.Described signal amplification circuit comprises triode Q1, resistance R 1, R2, R8, and the output terminal of comparer U1A is connected with the base stage of triode Q1 through resistance R 2, R3, and the collector of Q1 is connected with control chip through the USB_DET end.
The present invention utilize insert Schottky two pipe D1 produce after the USB device tube voltage again by comparer U1A relatively the voltage difference at D1 two ends realize detecting.The comparer positive input terminal is than negative input end level height when not inserting USB device, and comparer is output as height, instead then connects negative input end voltage ratio positive input terminal height after the USB device, output low level.Just whether insert to USB device as can be known by two different high-low levels.
Above-mentioned disclosed comparator circuit and signal amplification circuit; just the present invention one specifically uses; as long as can be used in the variation of judgement schottky diode both end voltage, the also circuit of output signal of can making comparisons rapidly; all should be within protection scope of the present invention, be replaced by operational amplifier, field effect transistor etc. as comparer U1A, triode Q1.
Claims (3)
1, a kind of USB device testing circuit, comprise the interface J1 that is connected with USB device, it is characterized in that: on the supply pin of interface J1, be connected with schottky diode D1, this schottky diode D1 is connected with judging the comparator circuit that diode D1 both end voltage changes, and comparator circuit connects with control chip by signal amplification circuit.
2, USB device testing circuit according to claim 1, it is characterized in that: described comparator circuit comprises comparer U1A and peripheral circuit thereof, the positive input terminal of comparer U1A is connected with the negative electrode of schottky diode D1 and the supply pin of interface J1, the negative input end of comparer U1A is connected with the anode of schottky diode D1 by resistance R 5, and the output terminal of comparer U1A is connected with the startup amplifying circuit.
3, USB device testing circuit according to claim 1 and 2, it is characterized in that: described signal amplification circuit comprises triode Q1, resistance R 1, R2, R8, the output terminal of comparer U1A is connected with the base stage of triode Q1 through resistance R 2, R3, and the collector of Q1 is connected with control chip through USB DET end.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200810027649A CN100578482C (en) | 2008-04-22 | 2008-04-22 | USB equipment detection circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200810027649A CN100578482C (en) | 2008-04-22 | 2008-04-22 | USB equipment detection circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101266587A true CN101266587A (en) | 2008-09-17 |
| CN100578482C CN100578482C (en) | 2010-01-06 |
Family
ID=39989012
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200810027649A Active CN100578482C (en) | 2008-04-22 | 2008-04-22 | USB equipment detection circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100578482C (en) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102385018A (en) * | 2010-09-06 | 2012-03-21 | 鸿富锦精密工业（深圳）有限公司 | External equipment connection sensing circuit |
| CN102568611A (en) * | 2011-12-29 | 2012-07-11 | 深圳市凌启电子有限公司 | Method, device and system for detecting moveable storage medium |
| CN102680818A (en) * | 2012-05-01 | 2012-09-19 | 珠海市杰理科技有限公司 | Circuit and method for real-time detection of master-slave machine with (USB) interface |
| CN103268143A (en) * | 2013-04-26 | 2013-08-28 | 福建星网视易信息系统有限公司 | Method for realizing electroless storage of USB (universal serial bus) mobile equipment |
| CN103678234A (en) * | 2013-12-06 | 2014-03-26 | 福建鑫诺通讯技术有限公司 | Interface circuit compatible with USB interfaces of various types |
| CN103954861A (en) * | 2014-04-23 | 2014-07-30 | 四川虹微技术有限公司 | Double-way USB load insertion detecting device |
| CN104423276A (en) * | 2013-08-23 | 2015-03-18 | 苏州宝时得电动工具有限公司 | Power management method and power management module |
| CN105259402A (en) * | 2015-10-27 | 2016-01-20 | 昆山洺九机电有限公司 | USB interface current and voltage test device |
| CN107247179A (en) * | 2017-05-03 | 2017-10-13 | 北京世纪龙脉科技有限公司 | A kind of voltage detecting circuit of USB device |
| CN109030929A (en) * | 2018-07-06 | 2018-12-18 | 杰华特微电子（杭州）有限公司 | load insertion detection circuit and method |
| CN110262992A (en) * | 2019-06-24 | 2019-09-20 | 无锡睿勤科技有限公司 | A kind of control device |
| CN111882852A (en) * | 2020-07-14 | 2020-11-03 | 深圳市信锐网科技术有限公司 | Access detection circuit, method, master device and storage medium |
-
2008
- 2008-04-22 CN CN200810027649A patent/CN100578482C/en active Active
Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102385018A (en) * | 2010-09-06 | 2012-03-21 | 鸿富锦精密工业（深圳）有限公司 | External equipment connection sensing circuit |
| CN102385018B (en) * | 2010-09-06 | 2016-06-01 | 国网山东省电力公司济宁供电公司 | External equipment connection sensing circuit |
| CN102568611A (en) * | 2011-12-29 | 2012-07-11 | 深圳市凌启电子有限公司 | Method, device and system for detecting moveable storage medium |
| CN102680818A (en) * | 2012-05-01 | 2012-09-19 | 珠海市杰理科技有限公司 | Circuit and method for real-time detection of master-slave machine with (USB) interface |
| CN102680818B (en) * | 2012-05-01 | 2015-02-18 | 珠海市杰理科技有限公司 | Circuit and method for real-time detection of master-slave machine with (USB) interface |
| CN103268143B (en) * | 2013-04-26 | 2016-03-30 | 福建星网视易信息系统有限公司 | A kind of USB mobile device realizes the method stored without electricity |
| CN103268143A (en) * | 2013-04-26 | 2013-08-28 | 福建星网视易信息系统有限公司 | Method for realizing electroless storage of USB (universal serial bus) mobile equipment |
| CN104423276A (en) * | 2013-08-23 | 2015-03-18 | 苏州宝时得电动工具有限公司 | Power management method and power management module |
| CN103678234B (en) * | 2013-12-06 | 2016-11-02 | 福建鑫诺通讯技术有限公司 | A kind of interface circuit of the multiple usb type of compatibility |
| CN103678234A (en) * | 2013-12-06 | 2014-03-26 | 福建鑫诺通讯技术有限公司 | Interface circuit compatible with USB interfaces of various types |
| CN103954861B (en) * | 2014-04-23 | 2016-04-20 | 四川虹微技术有限公司 | Pick-up unit is inserted in a kind of two-way USB load |
| CN103954861A (en) * | 2014-04-23 | 2014-07-30 | 四川虹微技术有限公司 | Double-way USB load insertion detecting device |
| CN105259402A (en) * | 2015-10-27 | 2016-01-20 | 昆山洺九机电有限公司 | USB interface current and voltage test device |
| CN107247179A (en) * | 2017-05-03 | 2017-10-13 | 北京世纪龙脉科技有限公司 | A kind of voltage detecting circuit of USB device |
| CN109030929A (en) * | 2018-07-06 | 2018-12-18 | 杰华特微电子（杭州）有限公司 | load insertion detection circuit and method |
| CN110262992A (en) * | 2019-06-24 | 2019-09-20 | 无锡睿勤科技有限公司 | A kind of control device |
| CN110262992B (en) * | 2019-06-24 | 2020-12-04 | 无锡睿勤科技有限公司 | Control device |
| CN111882852A (en) * | 2020-07-14 | 2020-11-03 | 深圳市信锐网科技术有限公司 | Access detection circuit, method, master device and storage medium |
| CN111882852B (en) * | 2020-07-14 | 2021-10-22 | 深圳市信锐网科技术有限公司 | Access detection circuit, method, master device and storage medium |
Also Published As
| Publication number | Publication date |
|---|---|
| CN100578482C (en) | 2010-01-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100578482C (en) | USB equipment detection circuit | |
| CN101740105B (en) | System and method for accessing memory card | |
| KR101978192B1 (en) | Charger detection with proprietary charger support | |
| CN106291210B (en) | USB interface detector, USB interface detection method, USB connector and electronic equipment | |
| US10983152B2 (en) | USB data pin impedance detection | |
| CN102055223B (en) | USB special charger recognition circuit | |
| CN105182154B (en) | A kind of USB detection circuit and method | |
| US20120023344A1 (en) | Semiconductor apparatus | |
| US20110087805A1 (en) | Multi-mode dongle for peripheral devices and associated methods | |
| CN101989749B (en) | Charging device and charging method | |
| US9270062B2 (en) | Electronic device and connector detection circuit thereof | |
| CN101778319B (en) | Method, system and mobile terminal for preventing misjudgment of earphone keystroke detection | |
| US10333260B2 (en) | High contact resistance detection | |
| TWI501085B (en) | Usb interface detection device | |
| CN103905955A (en) | Method and apparatus for detecting insertion of earphones, and interface circuit | |
| US20090174564A1 (en) | Dust detecting circuit | |
| US20130162298A1 (en) | Identifying circuit | |
| US20170192916A1 (en) | Automatic usb identification and communication system with star architecture and method thereof | |
| US9378107B2 (en) | Computer system and USB device detecting method thereof | |
| TWI255345B (en) | Low voltage detection circuit | |
| KR20170035081A (en) | Voltage regulator enhancing linearity | |
| CN101162254B (en) | Cpu slot testing device | |
| CN104678197A (en) | Test circuit | |
| CN111428842A (en) | Memory card identification method and mobile device | |
| US8525481B2 (en) | Device for measuring battery voltage |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| ASS | Succession or assignment of patent right |
Owner name: HUIZHOU DESAY SV AUTO. ELECTRONICS CO., LTD. Free format text: FORMER OWNER: HUIZHOU DESAY AUTOMOTIVE ELECTRONICS CO., LTD. Effective date: 20130111 |
|
| C41 | Transfer of patent application or patent right or utility model | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20130111 Address after: 516229 Guangdong province Huizhou Zhongkai hi tech Industrial Development Zone Pearl River Road No. 1 Patentee after: Huizhou Desay SV Auto. Electronics Co., Ltd. Address before: 516229 Guangdong city of Huizhou province Chen town DESAY third industrial zone Patentee before: Huizhou Desay Automotive Electronics Co., Ltd. |
|
| C56 | Change in the name or address of the patentee | ||
| CP03 | Change of name, title or address |
Address after: 516229 Guangdong province Huizhou City Zhongkai high tech Zone and five West Road No. 103 Patentee after: HUIZHOU DESAY SV AUTOMOTIVE CO., LTD. Address before: 516229 Guangdong province Huizhou Zhongkai hi tech Industrial Development Zone Pearl River Road No. 1 Patentee before: Huizhou Desay SV Auto. Electronics Co., Ltd. |