参数资料
型号: EVAL-ADF4252EBZ2
厂商: Analog Devices Inc
文件页数: 18/28页
文件大小: 0K
描述: BOARD EVAL ADF4252 NO VCO/FILTER
标准包装: 1
主要目的: 计时,频率合成器
嵌入式:
已用 IC / 零件: ADF4252
主要属性: 双路分数-N PLL II
次要属性: 板不包括环路滤波器和 VCO
已供物品: 部分安装的板,线缆,软件
相关产品: ADF4252BCPZ-R7-ND - IC PLL FREQ SYNTHESIZER 24LFCSP
ADF4252BCPZ-RL-ND - IC PLL FREQ SYNTHESIZER 24LFCSP
ADF4252BCPZ-ND - IC PLL FREQ SYNTHESIZER 24-LFCSP
REV. B
ADF4252
–25–
±100 kHz from the RF carrier. Harmonics of all spurs mentioned
will also appear. With the lowest spur setting enabled, the spurs
will be attenuated into the noise floor.
Prescaler
The prescaler limits the INT value. With P = 4/5, Nmin = 31.
With P = 8/9, Nmin = 91.
The prescaler can also influence the phase noise performance.
If INT < 91, a prescaler of 4/5 should be used. For applications
where INT > 91, P = 8/9 should be used for optimum noise
performance.
Filter Design—ADIsimPLL
A filter design and analysis program is available to help users
implement their PLL design. Visit www.analog.com/pll for a
free download of the ADIsimPLL software. The software
designs, simulates, and analyzes the entire PLL frequency
domain and time domain response. Various passive and active
filter architectures are allowed.
INTERFACING
The ADF4252 has a simple SPI compatible serial interface for
writing to the device. SCLK, SDATA, and LE control the data
transfer. When LE (latch enable) goes high, the 24 bits that have
been clocked into the input register on each rising edge of SCLK
will be transferred to the appropriate latch. See Figure 1 for the
Timing Diagram and Table I for the Control Bit Truth Table.
The maximum allowable serial clock rate is 20 MHz, which
means that the maximum update rate possible for the device is
833 kHz or one update every 1.2
s. This is certainly more than
adequate for systems that will have typical lock times in hun-
dreds of microseconds.
ADuC812
ADF4252
SCLK
SDATA
LE
CE
MUXOUT
(LOCK DETECT)
SCLOCK
MOSI
I/O PORTS
Figure 8. ADuC812 to ADF4252 Interface
ADuC812 Interface
Figure 8 shows the interface between the ADF4252 and the
ADuC812 microconverter. Since the ADuC812 is based on
an 8051 core, this interface can be used with any 8051 based
microcontroller. The microconverter is set up for SPI master
mode with CPHA = 0. To initiate the operation, the I/O port
driving LE is brought low. Each latch of the ADF4252 needs
(at most) a 24-bit word. This is accomplished by writing three
8-bit bytes from the microconverter to the device. When the third
byte has been written, the LE input should be brought high to
complete the transfer.
I/O port lines on the ADuC812 are also used to control power-
down (CE input) and to detect lock (MUXOUT configured as
lock detect and polled by the port input).
When operating in the mode described, the maximum SCLOCK
rate of the ADuC812 is 4 MHz. This means that the maximum
rate at which the output frequency can be changed will be 166 kHz.
ADSP-21xx
ADF4252
SCLK
SDATA
LE
CE
MUXOUT
(LOCK DETECT)
SCLK
DT
I/O FLAGS
TFS
Figure 9. ADSP-21xx to ADF4252 Interface
ADSP-2181 Interface
Figure 9 shows the interface between the ADF4252 and the
ADSP-21xx digital signal processor. Each latch of the ADF4252
needs (at most) a 24-bit word. The easiest way to accomplish this
using the ADSP-21xx family is to use the autobuffered transmit
mode of operation with alternate framing. This provides a means
for transmitting an entire block of serial data before an interrupt is
generated. Set up the word length for eight bits and use three memory
locations for each 24-bit word. To program each 24-bit latch, store
the three 8-bit bytes, enable the autobuffered mode, and then write
to the transmit register of the DSP. This last operation initiates the
autobuffer transfer.
PCB DESIGN GUIDELINES FOR CHIP SCALE PACKAGE
The leads on the chip scale package (CP-24) are rectangular. The
printed circuit board pad for these should be 0.1 mm longer than
the package land length and 0.05 mm wider than the package land
width. The land should be centered on the pad. This will ensure
that the solder joint size is maximized.
The bottom of the chip scale package has a central thermal pad.
The thermal pad on the printed circuit board should be at least
as large as this exposed pad. On the printed circuit board, there
should be a clearance of at least 0.25 mm between the thermal
pad and the inner edges of the pad pattern. This will ensure that
shorting is avoided.
Thermal vias may be used on the printed circuit board thermal pad
to improve thermal performance of the package. If vias are used,
they should be incorporated in the thermal pad at 1.2 mm pitch
grid. The via diameter should be between 0.3 mm and 0.33 mm,
and the via barrel should be plated with 1 oz copper to plug the via.
The user should connect the printed circuit board to AGND.
相关PDF资料
PDF描述
HMC05DRTH-S734 CONN EDGECARD 10POS DIP .100 SLD
RBC08DRTS-S93 CONN EDGECARD 16POS DIP .100 SLD
HMC05DREN-S734 CONN EDGECARD 10POS .100 EYELET
MAX8661ETL+T IC POWER MANAGE XSCALE 40-TQFN
HMC05DREH-S734 CONN EDGECARD 10POS .100 EYELET
相关代理商/技术参数
参数描述
EVAL-ADF4350EB1Z 功能描述:EVALUATION BOARD 1 FOR ADF4350 RoHS:是 类别:编程器,开发系统 >> 评估演示板和套件 系列:- 标准包装:1 系列:PSoC® 主要目的:电源管理,热管理 嵌入式:- 已用 IC / 零件:- 主要属性:- 次要属性:- 已供物品:板,CD,电源
EVAL-ADF4350EB2Z 功能描述:EVALUATION BOARD 2 FOR ADF4350 RoHS:是 类别:编程器,开发系统 >> 评估演示板和套件 系列:- 标准包装:1 系列:PSoC® 主要目的:电源管理,热管理 嵌入式:- 已用 IC / 零件:- 主要属性:- 次要属性:- 已供物品:板,CD,电源
EVAL-ADF4351EB1Z 功能描述:BOARD 1 EVAL FOR ADF4351 RoHS:否 类别:编程器,开发系统 >> 评估演示板和套件 系列:* 标准包装:1 系列:- 主要目的:电信,线路接口单元(LIU) 嵌入式:- 已用 IC / 零件:IDT82V2081 主要属性:T1/J1/E1 LIU 次要属性:- 已供物品:板,电源,线缆,CD 其它名称:82EBV2081
EVAL-ADF4360-0EB1 制造商:AD 制造商全称:Analog Devices 功能描述:Integrated Synthesizer and VCO
EVAL-ADF4360-1EB1 制造商:Analog Devices 功能描述:Evaluation Board For ADF4360-1