công cụ tìm kiếm bảng dữ liệu linh kiện điện tử
  Vietnamese  ▼
ALLDATASHEET.VN

X  

ADRF6702 bảng dữ liệu(PDF) 5 Page - Analog Devices

tên linh kiện ADRF6702
Giải thích chi tiết về linh kiện  High Dynamic Range RF Transmitter Signal Chain Using Single External Frequency Reference for DAC Sample Clock and IQ Modulator LO Generation
Download  8 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
nhà sản xuất  AD [Analog Devices]
Trang chủ  http://www.analog.com
Logo AD - Analog Devices

ADRF6702 bảng dữ liệu(HTML) 5 Page - Analog Devices

  ADRF6702 Datasheet HTML 1Page - Analog Devices ADRF6702 Datasheet HTML 2Page - Analog Devices ADRF6702 Datasheet HTML 3Page - Analog Devices ADRF6702 Datasheet HTML 4Page - Analog Devices ADRF6702 Datasheet HTML 5Page - Analog Devices ADRF6702 Datasheet HTML 6Page - Analog Devices ADRF6702 Datasheet HTML 7Page - Analog Devices ADRF6702 Datasheet HTML 8Page - Analog Devices  
Zoom Inzoom in Zoom Outzoom out
 5 / 8 page
background image
Circuit Note
CN-0243
Rev. 0 | Page 5 of 8
Applying the differential Butterworth filter gives significant
spur level reduction, as shown in Figure 8. The strongest spurs
are still at 2062 MHz, 2242 MHz, and the 2× DAC clock spur at
2400 MHz. All three spurious components have been reduced
significantly.
2400MHz
2242MHz
2062MHz
2098MHz
Figure 8. RF Spectrum Using 5th Order Butterworth Filter, Differential
Capacitors
The common-mode rejection of the DAC/IQ modulator
interface can often be improved by changing the topology of the
interface filter. In Figure 9, the input and output 4.7 pF caps are
replaced by common-mode capacitors (9.0 pF) from both sides
of the filter input and both sides of the filter output to ground.
This does not change the overall differential filter mode
response but does have an effect on this board on the overall
spurious content at RF. The harmonics mentioned earlier at
2400MHz
2242MHz
2062MHz
2098MHz
Figure 9. RF Spectrum Using 5th Order Butterworth Filter, Combination of
Differential and Common- Mode Capacitors Used in the DAC_Mod Filter
2062 MHz and 2242 MHz are down a few dB more, and there
has been about a 15 dB reduction in the 2× DAC clock
component, nearly to the noise floor.
The topology and results shown here may vary from layout to
layout, so it is always to the advantage of the designer to
experiment with the layout of the filter, specifically which mix
of differential and common-mode capacitors results in the
lowest overall spur floor.
Synthesizer Path and PLL Phase Noise
As shown in Figure 1, this circuit uses a single external
reference to generate the AD9122 DAC sample clock and the
reference clock for the PLL in the ADRF6702. The AD9516 is
fundamental in providing the flexibility to do this. The AD9516
contains a PLL and integrated VCO. It also contains a number
of outputs that can be programmed for differential LVPECL,
LVDS, or single-ended CMOS, with independent divider
settings for each output path. In this circuit, one of these output
paths is used for the DAC clock and another output is used for
the reference input of the fractional-N PLL in the ADRF6702.
The advantage of using a fractional PLL in the ADRF6702 is
twofold. First, the fractional PLL allows very fine tuning of the
output LO. As an example, with an input frequency of 38.4 MHz
and a programmed MOD value in the ADRF6702 of 1536, the
LO can be programmed in increments of 25 kHz. The second
advantage is that the reference frequency does not have to be
equal to LO freq/divider ratio, but can be much higher, leading
to a lower divider ratio. Because the output phase noise is a
function of the reference phase noise multiplied by the divider
ratio, this means inherently lower phase noise at RF.
One of the key metrics in a synthesizer system is the amount of
phase noise added by the individual PLL and dividers. Figure 10
shows the noise floor of the spectrum analyzer doing the
measurement (green trace), the phase noise of the reference
generator (red), and the phase noise of an output tone at an RF
frequency of 1961 MHz with an LO of 1940 MHz (yellow). The
combination of the PLL in the AD9516 and the ADRF6702 does
generate noticeably high close-in phase noise (less than 500 kHz
offset from carrier) but does not contribute significant
wideband noise to the system. The loop filters for the VCOs in
both the AD9516 and ADRF6702 are set to bandwidths of
~100 kHz in the measurement circuit. Close-in phase noise may
be reduced by lowering the bandwidth of these loop filters.
System specifications should be reviewed to determine how
much close-in phase noise can be tolerated for a given system.


Số phần tương tự - ADRF6702

nhà sản xuấttên linh kiệnbảng dữ liệuGiải thích chi tiết về linh kiện
logo
Analog Devices
ADRF6702 AD-ADRF6702 Datasheet
1Mb / 36P
   1200 MHz to 2400 MHz Quadrature Modulator with 1550 MHz to 2150 MHz Frac-N PLL
REV. 0
ADRF6702 AD-ADRF6702 Datasheet
1Mb / 36P
   1550 MHz to 2650 MHz Quadrature Modulator with 2100 MHz to 2600 MHz Frac-N PLL
REV. 0
ADRF6702 AD-ADRF6702 Datasheet
1Mb / 36P
   400 MHz to 1250 MHz Quadrature Modulator
REV. 0
ADRF6702 AD-ADRF6702 Datasheet
1Mb / 36P
   2050 MHz to 3000 MHz Quadrature Modulator
REV. 0
ADRF6702 AD-ADRF6702 Datasheet
1Mb / 36P
   1200 MHz to 2400 MHz Quadrature Modulator
REV. B
More results

Mô tả tương tự - ADRF6702

nhà sản xuấttên linh kiệnbảng dữ liệuGiải thích chi tiết về linh kiện
logo
Maxim Integrated Produc...
MAX11300PMB1 MAXIM-MAX11300PMB1 Datasheet
14Mb / 9P
   Internal or External Reference for ADC and DAC
Rev 2; 6/14
logo
Burr-Brown (TI)
ADS1201 BURR-BROWN-ADS1201 Datasheet
143Kb / 13P
   High Dynamic Range DELTA-SIGMA MODULATOR
logo
Texas Instruments
ADS1201 TI1-ADS1201 Datasheet
332Kb / 17P
[Old version datasheet]   High Dynamic Range DELTA-SIGMA MODULATOR
logo
Analog Devices
ADRF6820 AD-ADRF6820 Datasheet
1Mb / 45P
   Internal LO frequency range
logo
Maxim Integrated Produc...
MAXFILTERBRD MAXIM-MAXFILTERBRD Datasheet
718Kb / 5P
   CLK Pad for External Clock Frequency
19-4884; Rev 0; 8/09
logo
Adlink Technology Inc.
PCI-9527 ADLINK-PCI-9527 Datasheet
222Kb / 2P
   24-Bit High-Resolution Dynamic Signal Acquisition and Generation Modules
logo
Analog Devices
CN-0144 AD-CN-0144 Datasheet
238Kb / 4P
   Broadband Low Error Vector Magnitude Direct Conversion Transmitter Using LO Divide-by-2 Modulator
REV. C
logo
ON Semiconductor
AP0202AT ONSEMI-AP0202AT Datasheet
1Mb / 54P
   High-Dynamic Range Image Signal Processor
Rev. 4, 9/15 EN
logo
ATMEL Corporation
ATR4251 ATMEL-ATR4251_97 Datasheet
302Kb / 20P
   High Dynamic Range for AM and FM
logo
Analog Devices
CN-0311 AD-CN-0311 Datasheet
155Kb / 4P
   Broadband, Low Error Vector Magnitude (EVM) Direct Conversion Transmitter Using LO Divide-by-2 Modulator
REV. 0
More results


Html Pages

1 2 3 4 5 6 7 8


bảng dữ liệu tải về

Go To PDF Page


Link URL




Chính sách bảo mật
ALLDATASHEET.VN
Cho đến nay ALLDATASHEET có giúp ích cho doanh nghiệp của bạn hay không?  [ DONATE ] 

Alldatasheet là   |   Quảng cáo   |   Liên lạc với chúng tôi   |   Chính sách bảo mật   |   Trao đổi link   |   Tìm kiếm theo nhà sản xuất
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
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