參數(shù)資料
型號: ADF4157
廠商: Analog Devices, Inc.
英文描述: High Resolution 6 GHz Fractional-N Frequency Synthesizer
中文描述: 高分辨率6 GHz的分數(shù)N頻率合成器
文件頁數(shù): 9/20頁
文件大?。?/td> 320K
代理商: ADF4157
ADF4157
PHASE FREQUENCY DETECTOR (PFD) AND
CHARGE PUMP
The PFD takes inputs from the R counter and the N counter
and produces an output proportional to the phase and
frequency difference between them. Figure 14 is a simplified
schematic of the phase frequency detector. The PFD includes
a fixed delay element that sets the width of the antibacklash
pulse, which is typically 3 ns. This pulse ensures that there is no
dead zone in the PFD transfer function and gives a consistent
reference spur level.
Rev. 0 | Page 9 of 20
INPUT SHIFT REGISTERS
The ADF4157 digital section includes a 5-bit RF R counter,
a 12-bit RF N counter, and a 25-bit FRAC counter. Data is
clocked into the 32-bit shift register on each rising edge of CLK.
The data is clocked in MSB first. Data is transferred from
the shift register to one of five latches on the rising edge of LE.
The destination latch is determined by the state of the three
control bits (C3, C2, and C1) in the shift register. These are
the three LSBs, DB2, DB1, and DB0, as shown in
The truth table for these bits is shown in Table 6. Figure 16
shows a summary of how the latches are programmed.
Figure 2.
U3
CLR2
D2
U2
Q2
DOWN
UP
HI
HI
CP
–IN
+IN
CHARGE
PUMP
DELAY
CLR1
Q1
D1
U1
0
PROGRAM MODES
Table 6 and Figure 16 through Figure 21 show how to set up
the program modes in the ADF4157.
Several settings in the ADF4157 are double-buffered. These
include the LSB FRAC value, R counter value, reference doubler,
and current setting. This means that two events have to occur
before the part uses a new value of any of the double-buffered
settings. First, the new value is latched into the device by
writing to the appropriate register. Second, a new write must be
performed on Register R0.
For example, updating the fractional value can involve a write
to the 13 LSB bits in R1 and the 12 MSB bits in R0. R1 should
be written to first, followed by the write to R0. The frequency
change begins after the write to R0. Double buffering ensures
that the bits written to in R1 do not take effect until after
the write to R0.
Figure 14. PFD Simplified Schematic
MUXOUT AND LOCK DETECT
The output multiplexer on the ADF4157 allows the user to
access various internal points on the chip. The state of
MUXOUT is controlled by M4, M3, M2, and M1 (see Figure
17). Figure 15 shows the MUXOUT section in block diagram
form.
Table 6. C3, C2, and C1 Truth Table
Control Bits
C3
C2
0
0
0
0
0
1
0
1
1
0
Register
Register R0
Register R1
Register R2
Register R3
Register R4
0
ANALOG LOCK DETECT
MUXOUT
DV
DD
THREE-STATE OUTPUT
N DIVIDER OUTPUT
DV
DD
DGND
DGND
R DIVIDER OUTPUT
DIGITAL LOCK DETECT
SERIAL DATA OUTPUT
CLK DIVIDER OUTPUT
R DIVIDER/2
N DIVIDER/2
CONTROL
MUX
C1
0
1
0
1
0
Figure 15. MUXOUT Schematic
相關PDF資料
PDF描述
ADF4157BCPZ1 High Resolution 6 GHz Fractional-N Frequency Synthesizer
ADF4157BCPZ-RL1 High Resolution 6 GHz Fractional-N Frequency Synthesizer
ADF4157BCPZ-RL71 High Resolution 6 GHz Fractional-N Frequency Synthesizer
ADF4157BRUZ1 High Resolution 6 GHz Fractional-N Frequency Synthesizer
ADF4157BRUZ-RL1 High Resolution 6 GHz Fractional-N Frequency Synthesizer
相關代理商/技術參數(shù)
參數(shù)描述
ADF4157BCPZ 功能描述:IC PLL FREQ SYNTH 6GHZ 20LFCSP RoHS:是 類別:集成電路 (IC) >> 時鐘/計時 - 時鐘發(fā)生器,PLL,頻率合成器 系列:- 標準包裝:1,000 系列:Precision Edge® 類型:時鐘/頻率合成器 PLL:無 輸入:CML,PECL 輸出:CML 電路數(shù):1 比率 - 輸入:輸出:2:1 差分 - 輸入:輸出:是/是 頻率 - 最大:10.7GHz 除法器/乘法器:無/無 電源電壓:2.375 V ~ 3.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:16-VFQFN 裸露焊盤,16-MLF? 供應商設備封裝:16-MLF?(3x3) 包裝:帶卷 (TR) 其它名稱:SY58052UMGTRSY58052UMGTR-ND
ADF4157BCPZ1 制造商:AD 制造商全稱:Analog Devices 功能描述:High Resolution 6 GHz Fractional-N Frequency Synthesizer
ADF4157BCPZ-RL 功能描述:IC PLL FREQ SYNTH 6GHZ 20LFCSP RoHS:是 類別:集成電路 (IC) >> 時鐘/計時 - 時鐘發(fā)生器,PLL,頻率合成器 系列:- 標準包裝:1,000 系列:Precision Edge® 類型:時鐘/頻率合成器 PLL:無 輸入:CML,PECL 輸出:CML 電路數(shù):1 比率 - 輸入:輸出:2:1 差分 - 輸入:輸出:是/是 頻率 - 最大:10.7GHz 除法器/乘法器:無/無 電源電壓:2.375 V ~ 3.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:16-VFQFN 裸露焊盤,16-MLF? 供應商設備封裝:16-MLF?(3x3) 包裝:帶卷 (TR) 其它名稱:SY58052UMGTRSY58052UMGTR-ND
ADF4157BCPZ-RL1 制造商:AD 制造商全稱:Analog Devices 功能描述:High Resolution 6 GHz Fractional-N Frequency Synthesizer
ADF4157BCPZ-RL7 功能描述:IC PLL FREQ SYNTH 6GHZ 20LFCSP RoHS:是 類別:集成電路 (IC) >> 時鐘/計時 - 時鐘發(fā)生器,PLL,頻率合成器 系列:- 標準包裝:1,000 系列:Precision Edge® 類型:時鐘/頻率合成器 PLL:無 輸入:CML,PECL 輸出:CML 電路數(shù):1 比率 - 輸入:輸出:2:1 差分 - 輸入:輸出:是/是 頻率 - 最大:10.7GHz 除法器/乘法器:無/無 電源電壓:2.375 V ~ 3.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:16-VFQFN 裸露焊盤,16-MLF? 供應商設備封裝:16-MLF?(3x3) 包裝:帶卷 (TR) 其它名稱:SY58052UMGTRSY58052UMGTR-ND