- 您现在的位置：买卖IC网 > PDF目录225341 > TRF2050PW (TEXAS INSTRUMENTS INC) PLL FREQUENCY SYNTHESIZER, 1200 MHz, PDSO20 PDF资料下载
参数资料
| 型号： | TRF2050PW |
| 厂商： | TEXAS INSTRUMENTS INC |
| 元件分类： | PLL合成/DDS/VCOs |
| 英文描述： | PLL FREQUENCY SYNTHESIZER, 1200 MHz, PDSO20 |
| 封装： | PLASTIC, SO-20 |
| 文件页数： | 21/34页 |
| 文件大小： | 543K |
| 代理商： | TRF2050PW |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页当前第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页
TRF2050
LOW-VOLTAGE 1.2-GHz FRACTIONAL-N/INTEGER-N SYNTHESIZER
SLWS030E– JUNE 1996 – REVISED OCTOBER 2000
28
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
PRINCIPLES OF OPERATION1234
main divider – fractional-N sidebands and compensation (continued)
D Determine the values of CN and RN for the main PHP charge-pump peak current of 500 A. Assume that
a midrange value of CN equals 128.
RN(k
W) + 18.75
CN
256
1
I(mA)
–0.75
+ 18.75
128
256
1
0.5 mA
–0.75
+ 18 kW
D The value of the fundamental compensation pulse magnitude calculated in step 3 is fixed and the
compensation pulse width calculated in step 2 is also fixed. However, because the VCO can tune over a
significant range of frequencies, the pulse width of the fractional-N portion of the main PHP charge-pump
waveform varies; thus, the area of the same waveform varies. In order to maintain equal areas under the
fractional-N portion of the main PHP charge-pump and compensation waveforms, CN must vary with the
VCO frequency. As the VCO frequency increases, the fractional-N portion of the main PHP charge-pump
waveform pulse width decreases proportionally, thereby decreasing the area under the same waveform.
Therefore, CN is adjusted to equalize the main PHP and compensation waveform areas, as follows:
FracPW-LWR = 132.557 ps for fVCO = 942.99 MHz
FracPW-UPR = 129.815 ps for fVCO = 962.91 MHz
The fundamental area of the fractional-N portion of the main PHP charge-pump waveform (step 1) is
calculated as 0.065593 picosecond x amperes. If you calculate the fundamental area of the fractional-N
portion of the main PHP charge-pump waveform using the actual pulse widths above in place of the average
pulse width calculated in step 1, the fractional-N main PHP areas is obtained as follows:
FracArea-LWR = 132.557 ps – 0.500 mA = 0.066279 ( ps × amps)
FracArea-UPR = 129.815 ps – 0.500 mA = 0.064691 (ps × amps)
The actual areas under the fractional-N portion of the main PHP waveform require slight modification in the
charge-pump current. The variation of CN required for area equalization is determined using a simple ratio
form:
CN
LWR +
Frac
Area–AVG
CN
AVG +
0.065593
0.066279
128
+ 126
CN
UPR +
Frac
Area–AVG
Frac
Area–UPR
CN
AVG +
0.065593
0.064691
128
+ 130
Frac
Area–UPR
Therefore, for this example, CN can vary from 126-130 over the VCO frequency range of 942.99 – 962.91
MHz for optimum fractional-N sideband suppression. Due to component and circuit tolerances, additional
deviations in CN may be appropriate.
auxiliary divider
The input signal on AUXIN is amplified by a single-ended, ac-coupled input buffer/amplifier that has sufficient
sensitivity (200 mVpp at 200 MHz) for direct connection to a typical VCO. The 12-bit (NA) auxiliary divider
incorporates a divide by 1 (PA = 1) or divide by 4 (PA = 0) prescaler. The total division ratio can be expressed
as:
NTotal = 4 x NA where PA = 0
NTotal = NA, where PA = 1 and NA = 4 to 4095
相关PDF资料 |
PDF描述 |
|---|---|
| TRF2056PWR | PLL FREQUENCY SYNTHESIZER, 1200 MHz, PDSO20 |
| TRF4000 | Pcs RX-mixer |
| TRF4002PWP | 1850 MHz - 1910 MHz RF/MICROWAVE NARROW BAND MEDIUM POWER AMPLIFIER |
| TRS-1300-1305-8310 | TRIPLE COLOR LED ARRAY |
| TRS-1300-1311-8310 | DUAL COLOR LED ARRAY |
相关代理商/技术参数 |
参数描述 |
|---|---|
| TRF2052 | 制造商:TI 制造商全称:Texas Instruments 功能描述:LOW-VOLTAGE 2-GHz SYNTHESIZER |
| TRF2052PW | 功能描述:IC LV 2-GHZ SYNTH 20-TSSOP RoHS:否 类别:集成电路 (IC) >> 时钟/计时 - 时钟发生器，PLL，频率合成器 系列:- 标准包装:2,000 系列:- 类型:PLL 频率合成器 PLL:是 输入:晶体 输出:时钟 电路数:1 比率 - 输入:输出:1:1 差分 - 输入:输出:无/无 频率 - 最大:1GHz 除法器/乘法器:是/无 电源电压:4.5 V ~ 5.5 V 工作温度:-20°C ~ 85°C 安装类型:表面贴装 封装/外壳:16-LSSOP（0.175"，4.40mm 宽） 供应商设备封装:16-SSOP 包装:带卷 (TR) 其它名称:NJW1504V-TE1-NDNJW1504V-TE1TR |
| TRF2056 | 制造商:TI 制造商全称:Texas Instruments 功能描述:LOW-VOLTAGE 1,2-GHz FRACTIONAL-N/INTEGER-N SYNTHESIZER |
| TRF2056PW | 制造商:Rochester Electronics LLC 功能描述:- Bulk |
| TRF2253PWR | 制造商:Texas Instruments 功能描述: |
发布紧急采购，3分钟左右您将得到回复。