參數(shù)資料
型號: LMX2470
廠商: National Semiconductor Corporation
英文描述: 2.6 GHz Delta-Sigma Fractional-N PLL with 800 MHz Integer-N PLL
中文描述: 2.6 GHz的Δ-Σ分數(shù)N與800兆赫整數(shù)N分頻PLL鎖相環(huán)
文件頁數(shù): 1/36頁
文件大?。?/td> 453K
代理商: LMX2470
LMX2470
2.6 GHz Delta-Sigma Fractional-N PLL with 800 MHz
Integer-N PLL
General Description
The LMX2470 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 LMX2470 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 LMX2470 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 LMX2470 via a three line MICROWIRE interface
(Data, Clock, Load Enable). Nominal supply voltage is 2.5 V.
The LMX2470 features a typical current consumption of 4.1
mA at 2.5 V. The LMX2470 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 30 MHz
n
Hardware and software power-down control
n
Ultra low consumption: I
CC
= 4.1 mA (typical)
Applications
n
Cellular Phones and Base Stations
CDMA, WCDMA, GSM/GPRS, TDMA, EDGE, PDC
n
Applications requiring fine frequency resolution
n
Satellite and Cable TV Tuners
n
WLAN Standards
Functional Block Diagram
20059301
April 2003
L
2003 National Semiconductor Corporation
DS200593
www.national.com
相關PDF資料
PDF描述
LMX2470SLEX 2.6 GHz Delta-Sigma Fractional-N PLL with 800 MHz Integer-N PLL
LMX2485 50 MHz - 3.0 GHz High Performance Delta-Sigma Low Power Dual PLLatinum⑩ Frequency Synthesizers with 800 MHz Integer PLL
LMX2485E 50 MHz - 3.0 GHz High Performance Delta-Sigma Low Power Dual PLLatinum⑩ Frequency Synthesizers with 800 MHz Integer PLL
LMX2485ESQ 50 MHz - 3.0 GHz High Performance Delta-Sigma Low Power Dual PLLatinum⑩ Frequency Synthesizers with 800 MHz Integer PLL
LMX2485ESQX 50 MHz - 3.0 GHz High Performance Delta-Sigma Low Power Dual PLLatinum⑩ Frequency Synthesizers with 800 MHz Integer PLL
相關代理商/技術參數(shù)
參數(shù)描述
LMX2470EVAL 功能描述:時鐘和定時器開發(fā)工具 LMX2470 EVAL BOARD RoHS:否 制造商:Texas Instruments 產(chǎn)品:Evaluation Modules 類型:Clock Conditioners 工具用于評估:LMK04100B 頻率:122.8 MHz 工作電源電壓:3.3 V
LMX2470SLEX 功能描述:鎖相環(huán) - PLL RoHS:否 制造商:Silicon Labs 類型:PLL Clock Multiplier 電路數(shù)量:1 最大輸入頻率:710 MHz 最小輸入頻率:0.002 MHz 輸出頻率范圍:0.002 MHz to 808 MHz 電源電壓-最大:3.63 V 電源電壓-最小:1.71 V 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝 / 箱體:QFN-36 封裝:Tray
LMX2470SLEX/NOPB 功能描述:鎖相環(huán) - PLL RoHS:否 制造商:Silicon Labs 類型:PLL Clock Multiplier 電路數(shù)量:1 最大輸入頻率:710 MHz 最小輸入頻率:0.002 MHz 輸出頻率范圍:0.002 MHz to 808 MHz 電源電壓-最大:3.63 V 電源電壓-最小:1.71 V 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝 / 箱體:QFN-36 封裝:Tray
LMX2471 制造商:NSC 制造商全稱:National Semiconductor 功能描述:3.6 GHz Delta-Sigma Fractional-N PLL with 1.7 GHz Integer-N PLL
LMX2471 WAF 制造商:Texas Instruments 功能描述: