參數(shù)資料
型號: FS6131-01
廠商: ON SEMICONDUCTOR
元件分類: PLL合成/DDS/VCOs
英文描述: PLL FREQUENCY SYNTHESIZER, 27 MHz, PDSO16
封裝: 0.150 INCH, SOP-16
文件頁數(shù): 27/40頁
文件大小: 746K
代理商: FS6131-01
33
AMI Semiconductor - Rev. 2.0, Jun. 05
www.amis.com
FS6131-01/FS6131-01g Programmable Line Lock Clock Generator IC
Data Sheet
Deciding how to apportion the denominator integers between the reference divider and the post divider is an iterative process. To obtain the best
performance, the VCO should be operated at the highest frequency possible without exceeding its upper limit of 230MHz. (see Table 15). The
VCO frequency (fVCO) can be calculated by
R
F
REF
VCO
N
f
=
Recall that the reference divider can have a value between 1 and 4096, but the post divider is limited to values derived from
3
2
1
P
Px
N
=
where the values NP1, NP2 and NP3 are found in Table 8.
In this example, the smallest integer that can be removed from the denominator of Eqn. 2 is three. Set the post divider at NPx=3, and the ratio of
fCLK to fREF becomes (from Eqn. 1)
()
3
1
7
3
11
5
2
1
3
=
REF
CLK
f
Unfortunately, a post divider modulus of three requires a VCO frequency of 300MHz, which is greater than the allowable fVCO noted in Table 15.
For the best PLL performance, program the post divider modulus to allow the VCO to operate at a nominal frequency that is at least 70MHz but
less then 230MHz. Therefore, the reference divider cannot be reduced below the modulus of 327 (or 63) as shown in Eqn. 2.
However, the VCO can still be operated at a frequency higher than fCLK. Multiplying both the numerator and the denominator by two does not alter
the output frequency, but it does increase the VCO frequency.
()
2
1
63
880
2
1
7
3
2
11
5
2
1
2
1
3
=
=
=
Px
R
F
REF
CLK
N
f
As Eqn. 3 shows, the VCO frequency can be doubled by multiplying the feedback divider by two. Set the post divider to two to return the output
frequency to the desired modulus. These divider settings place the VCO frequency at 200MHz.
12.2 Example Programming
To generate 100.000MHz from 14.318MHz, program the following (refer to Figure 25):
Set the reference divider input to select the VCXO via REFDSRC=0
Set the PFD input to select the reference divider and the feedback divider via PDREF=0 and PDFBK=0
Set the reference divider (NR) to a modulus of 63 via REFDIV[11:0]
Set the feedback divider input to select the VCO via FBKDSRC=1
Set the feedback divider (NF) to a modulus of 880 via FBKDIV[14:0]
Set NP1=2, NP2=1 and NP3=1 for a combined post divider modulus of NPx=2 via POST1[1:0], POST2[1:0] and POST3[1:0].
Select the internal loop filter via EXTLF=0
Set XLVTEN=0 and XLPDEN=1 to disable the VCXO fine tune and the crystal loop phase frequency detector
Set VCOSPD=0 to select the VCO high speed range
相關(guān)PDF資料
PDF描述
FS6S0965R-YDTU 36 A SWITCHING REGULATOR, 150 kHz SWITCHING FREQ-MAX, PZFM5
FS6S0965R-TU 36 A SWITCHING REGULATOR, 150 kHz SWITCHING FREQ-MAX, PSFM5
FS6S1265RE-YDTU 48 A SWITCHING REGULATOR, 150 kHz SWITCHING FREQ-MAX, PZFM5
FS6S1265RB-YDTU 48 A SWITCHING REGULATOR, 150 kHz SWITCHING FREQ-MAX, PZFM5
FS6S0965RT-YDTU 36 A SWITCHING REGULATOR, 150 kHz SWITCHING FREQ-MAX, PZFM5
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
FS6131-01G 制造商:ONSEMI 制造商全稱:ON Semiconductor 功能描述:Programmable Line Lock Clock Generator IC
FS6131-01G-XTD 功能描述:時鐘發(fā)生器及支持產(chǎn)品 I2C PROG PLL CLK RoHS:否 制造商:Silicon Labs 類型:Clock Generators 最大輸入頻率:14.318 MHz 最大輸出頻率:166 MHz 輸出端數(shù)量:16 占空比 - 最大:55 % 工作電源電壓:3.3 V 工作電源電流:1 mA 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:QFN-56
FS6131-01G-XTP 功能描述:時鐘發(fā)生器及支持產(chǎn)品 I2C PROG PLL CLK RoHS:否 制造商:Silicon Labs 類型:Clock Generators 最大輸入頻率:14.318 MHz 最大輸出頻率:166 MHz 輸出端數(shù)量:16 占空比 - 最大:55 % 工作電源電壓:3.3 V 工作電源電流:1 mA 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:QFN-56
FS6131-01I-XTD 功能描述:時鐘發(fā)生器及支持產(chǎn)品 I2C PROG PLL CLK (IND) RoHS:否 制造商:Silicon Labs 類型:Clock Generators 最大輸入頻率:14.318 MHz 最大輸出頻率:166 MHz 輸出端數(shù)量:16 占空比 - 最大:55 % 工作電源電壓:3.3 V 工作電源電流:1 mA 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:QFN-56
FS6131-01I-XTP 功能描述:時鐘發(fā)生器及支持產(chǎn)品 I2C PROG PLL CLK IND RoHS:否 制造商:Silicon Labs 類型:Clock Generators 最大輸入頻率:14.318 MHz 最大輸出頻率:166 MHz 輸出端數(shù)量:16 占空比 - 最大:55 % 工作電源電壓:3.3 V 工作電源電流:1 mA 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:QFN-56