 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
LMX2471 Datasheet(PDF) 1 Page - National Semiconductor (TI) |
|
|
|
|||||||||||||||||||||||||||||
LMX2471 Datasheet(HTML) 1 Page - National Semiconductor (TI) |
|
|
1 / 36 page  LMX2471 3.6 GHz Delta-Sigma Fractional-N PLL with 1.7 GHz Integer-N PLL General Description The LMX2471 is a low power, high performance delta-sigma fractional-N PLL with an auxiliary integer-N PLL. The device is fabricated using National Semiconductor’s advanced BiC- MOS process. With delta-sigma architecture, fractional spur compensation is achieved with noise shaping capability of the delta-sigma modulator and the inherent low pass filtering of the PLL loop filter. Fractional spurs at lower frequencies are pushed to higher frequencies outside the loop bandwidth. Unlike ana- log compensation, the digital feedback techniques used in the LMX2471 are highly resistant to changes in temperature and variations in wafer processing. With delta-sigma archi- tecture, the ability to push close in spur and phase noise energy to higher frequencies is a direct function of the modu- lator order. The higher the order, the more this energy can be spread to higher frequencies. The LMX2471 has a program- mable modulator up to order four, which allows the designer to select the optimum modulator order to fit the phase noise, spur, and lock time requirements of the system. Programming is fast and simple. Serial data is transferred into the LMX2471 via a three line MICROWIRE interface (Data, Clock, Load Enable). Nominal supply voltage is 2.5 V. The LMX2471 features a typical current consumption of 5.6 mA at 2.5 V. The LMX2471 is available in a 24 lead 3.5 X 4.5 X 0.6 mm package. Features n Low in-band phase noise and low fractional spurs n 12 bit or 22 bit selectable fractional modulus n Up to 4th order programmable delta-sigma modulator n Enhanced Anti-Cycle Slip Fastlock Circuitry Fastlock Cycle slip reduction Integrated timeout counters n Digital lock detect output n Prescalers allow wide range of N values RF PLL: 16/17/20/21 IF PLL: 8/9 or 16/17 n Crystal Reference Frequency up to 110 MHz n On-chip crystal reference frequency doubler. n Phase Comparison Frequency up to 50 MHz n Hardware and software power-down control n Ultra low consumption: I CC = 5.6 mA (typical) Applications n Cellular Phones and Base Stations n Applications requiring fine frequency resolution n Satellite and Cable TV Tuners n WLAN Standards Functional Block Diagram 20072101 November 2003 © 2003 National Semiconductor Corporation DS200721 www.national.com |
Similar Part No. - LMX2471 |
|
Similar Description - LMX2471 |
|
|
Link URL |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link to Datasheet | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
