CN102624417A - Method for supplying USB (Universal Serial Bus) 2.0 transceiver with 480MHz crystal oscillation for work though frequency multiplication and frequency division on 25MHz crystal oscillation - Google Patents
Method for supplying USB (Universal Serial Bus) 2.0 transceiver with 480MHz crystal oscillation for work though frequency multiplication and frequency division on 25MHz crystal oscillation Download PDFInfo
- Publication number
- CN102624417A CN102624417A CN2012100507712A CN201210050771A CN102624417A CN 102624417 A CN102624417 A CN 102624417A CN 2012100507712 A CN2012100507712 A CN 2012100507712A CN 201210050771 A CN201210050771 A CN 201210050771A CN 102624417 A CN102624417 A CN 102624417A
- Authority
- CN
- China
- Prior art keywords
- signal
- 25mhz
- 480mhz
- crystal oscillation
- frequency multiplication
- 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.)
- Pending
Links
Images
Landscapes
- Transceivers (AREA)
Abstract
The invention provides a method for supplying USB (Universal Serial Bus) 2.0 transceiver with 480MHz crystal oscillation for work though frequency multiplication and frequency division on 25MHz crystal oscillation, which comprises the following steps of: generating a 25MHz signal by a 25MHz crystal oscillating circuit; carrying out frequency multiplication on the 25MHz signal to form a 300MHz signal; carrying out frequency division on the 300MHz signal to form a 12MHz signal; and carrying out frequency multiplication on the 12MHz signal to form the 480MHz signal to supply to a USB2.0 transceiver circuit. According to the method provided by the invention, an existing circuit has strong reusability and the development periods of related products are shortened.
Description
Technical field
The present invention is a kind of through external 25MHz crystal oscillator frequency multiplication and frequency division are realized that 480MHz supplies with the method for USB2.0 transceiver circuit work.
Background technology
USB interface is widely used in various terminals such as PC, panel computer, MP3, digital camera, DV, mobile phone, GPS or the like.USB device is widely used and is easy to carry, so promoted widely.
USB2.0 provides the signal frequency of 480MHz, transferring large number of data in a short period of time, but this has also proposed higher requirement to the design of transceiver circuit, and transceiver circuit needs the clock signal of 480MHz and carries out work.In general, the signal of 480MHz all is to be produced by the crystal of the outside 12MHz PLL circuit through internal oscillator circuit and 40 frequencys multiplication.In USB Fast Ethernet adapter chip, the crystal that also needs 25MHz is used for the work of Ethernet transceiver circuit.So, can unite two into one two required crystal of chip? If of course, just can reduce production cost and PCB area.
To merge the two, can consider to generate the signal of 12MHz so from the 25MHz signal.Because two kinds of signals are not the relations of integral multiple, if settle at one go, just need use the PLL circuit of mark frequency multiplication.But the circuit versatility of non-integral number frequency multiplication is not strong, so the IP supplier of chip design does not generally provide, need do custom design.The significantly increase that custom design can be brought cost and development time brings certain risk simultaneously.
Therefore; To above-mentioned deficiency, the invention provides a kind of through external 25MHz crystal oscillator frequency multiplication and frequency division are realized that 480MHz supplies with the method for USB2.0 transceiver circuit work, through this method; Produce earlier the 25MHz signal, then to the 25MHz signal frequency multiplication to the 300MHz signal; The 300MHz signal frequency split is to the 12MHz signal; Supply with the USB2.0 transceiver circuit to the 12MHz signal frequency multiplication to the 480MHz signal again.What utilize in the middle of this all is the relation of integer frequency and integral frequency divisioil, and sort circuit is mostly to have ready-made IP or module to use.Thereby can shorten the chip development cycle, and can not bring additional risk.
Summary of the invention
For above purpose, the invention provides a kind of passing through external 25MHz crystal oscillator frequency multiplication and frequency division are realized that 480MHz supplies with the method for USB2.0 transceiver circuit work, this method comprises:
1,25MHz crystal oscillating circuit; The 25MHz signal frequency multiplication is to the 300MHz signal; The 300MHz signal frequency split is to the 12MHz signal; The 12MHz signal frequency multiplication is to the 480MHz signal.
2, oscillating circuit and frequency multiplication frequency dividing circuit all are integrated on the same chip.
3, the 480MHz signal that produces is used for the USB2.0 transceiver circuit.
Description of drawings
In claims of patent application of the present invention, pointed out theme of the present invention particularly, and clearly it has been proposed patent protection.Yet with reference to explanation and accompanying drawing, can better understand of the present invention about structure and implementation method with and purpose, characteristic and advantage.
Fig. 1 electrical block diagram;
Though here declarative description some characteristic of the present invention and a kind of implementation method, for the professional and technical personnel, many modifications, replacement, variation and equivalent substitution will appear.Therefore, protection scope of the present invention is as the criterion with the scope of appended claim.
Claims (3)
1. one kind is passed through external 25MHz crystal oscillator frequency multiplication and frequency division are realized that 480MHz supplies with the method for USB2.0 transceiver circuit work, it is characterized in that, comprising: the 25MHz crystal oscillating circuit; The 25MHz signal frequency multiplication is to the 300MHz signal; The 300MHz signal frequency split is to the 12MHz signal; The 12MHz signal frequency multiplication is to the 480MHz signal.
2. like claims 1 described method, it is characterized in that described oscillating circuit and frequency multiplication frequency dividing circuit all are integrated on the same chip.
3. like claims 1 described method, it is characterized in that the 480MHz signal that is produced is used for the USB2.0 transceiver circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012100507712A CN102624417A (en) | 2012-03-01 | 2012-03-01 | Method for supplying USB (Universal Serial Bus) 2.0 transceiver with 480MHz crystal oscillation for work though frequency multiplication and frequency division on 25MHz crystal oscillation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012100507712A CN102624417A (en) | 2012-03-01 | 2012-03-01 | Method for supplying USB (Universal Serial Bus) 2.0 transceiver with 480MHz crystal oscillation for work though frequency multiplication and frequency division on 25MHz crystal oscillation |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102624417A true CN102624417A (en) | 2012-08-01 |
Family
ID=46564115
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012100507712A Pending CN102624417A (en) | 2012-03-01 | 2012-03-01 | Method for supplying USB (Universal Serial Bus) 2.0 transceiver with 480MHz crystal oscillation for work though frequency multiplication and frequency division on 25MHz crystal oscillation |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102624417A (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5535377A (en) * | 1994-01-31 | 1996-07-09 | Dell Usa, L.P. | Method and apparatus for low latency synchronization of signals having different clock speeds |
| CN1784665A (en) * | 2003-05-09 | 2006-06-07 | 皇家飞利浦电子股份有限公司 | Method for data signal transfer across different clock-domains |
| CN101944912A (en) * | 2010-07-30 | 2011-01-12 | 炬力集成电路设计有限公司 | Monocrystal oscillator electronic device and method for determining frequency division coefficient |
| CN102331979A (en) * | 2011-09-28 | 2012-01-25 | 成都市芯锐微电子有限公司 | Dynamic clock frequency calibration method applied to universal serial bus (USB) equipment |
-
2012
- 2012-03-01 CN CN2012100507712A patent/CN102624417A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5535377A (en) * | 1994-01-31 | 1996-07-09 | Dell Usa, L.P. | Method and apparatus for low latency synchronization of signals having different clock speeds |
| CN1784665A (en) * | 2003-05-09 | 2006-06-07 | 皇家飞利浦电子股份有限公司 | Method for data signal transfer across different clock-domains |
| CN101944912A (en) * | 2010-07-30 | 2011-01-12 | 炬力集成电路设计有限公司 | Monocrystal oscillator electronic device and method for determining frequency division coefficient |
| CN102331979A (en) * | 2011-09-28 | 2012-01-25 | 成都市芯锐微电子有限公司 | Dynamic clock frequency calibration method applied to universal serial bus (USB) equipment |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9158329B2 (en) | Bridge device | |
| CN102945061B (en) | For generation of circuit and the method for USB external clock | |
| TWI721580B (en) | Touch screen detection chip assembly and terminal device thereof | |
| CN106444964A (en) | Clock system for FPGA, and server | |
| CN102624417A (en) | Method for supplying USB (Universal Serial Bus) 2.0 transceiver with 480MHz crystal oscillation for work though frequency multiplication and frequency division on 25MHz crystal oscillation | |
| CN202904429U (en) | Circuit for producing universal serial bus (USB) peripheral clock | |
| CN111147957A (en) | Gas meter data acquisition device with universal communication interface | |
| CN203352584U (en) | Wireless communication system | |
| CN202976056U (en) | OSEK/VDX standard compatible configuration tool configured based on Artop | |
| CN203434934U (en) | Extended crystal oscillation clock circuit, circuit board and mobile terminal | |
| CN102982002B (en) | The application process of crystal oscillator and SOC in a kind of system level chip SOC | |
| CN204440909U (en) | One side PCB wireless music player and main control circuit thereof | |
| CN203166892U (en) | Wireless audio reception apparatus used for vehicle system | |
| CN102929330A (en) | Circuit and method for generating USB external clock | |
| CN206932226U (en) | A kind of clock synchronization circuit and terminal | |
| RU119141U1 (en) | PROGRAMMER OF TELEVISION MEMORY ICs | |
| CN204408498U (en) | A kind of differential signal generation unit | |
| CN204536560U (en) | A kind of multisystem satellite navigation signal of USB3.0 interface generates board | |
| CN204597909U (en) | A kind of crystal oscillator of high stable multiple-channel output | |
| CN202443042U (en) | Multi-mode modulating signal generator | |
| CN201032711Y (en) | Frequency generator of digital direct synthesizer | |
| CN215682257U (en) | Frequency hopping source capable of simplifying management of main control chip | |
| JP2014131283A (en) | Crystal oscillator frequency adjustment device | |
| TWI475397B (en) | Usb3.0 clock frequency generation device without crystal oscillator | |
| CN102377446A (en) | Wireless USB (Universal Serial Bus) search network card |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20120801 |