參數(shù)資料
型號: LMX2470
廠商: National Semiconductor Corporation
英文描述: 2.6 GHz Delta-Sigma Fractional-N PLL with 800 MHz Integer-N PLL
中文描述: 2.6 GHz的Δ-Σ分數(shù)N與800兆赫整數(shù)N分頻PLL鎖相環(huán)
文件頁數(shù): 17/36頁
文件大?。?/td> 453K
代理商: LMX2470
Bench Test Setups
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Input Impedance Measurement Procedure
The above block diagram shows the test procedure measur-
ing the input impedance for the LMX2470. This applies to the
FinRF, FinIF, and OSCin pins. The basic test procedure is to
calibrate the network analyzer, ensure that the part is pow-
ered up, and then measure the input impedance. The net-
work analyzer can be calibrated by using either calibration
standards or by soldering resistors directly to the evaluation
board. An open can be implemented by putting no resistor, a
short can be implemented by using a 0 ohm resistor, and a
short can be implemented by using two 100 ohm resistors in
parallel. Note that no DC blocking capacitor is used for this
test procedure. This is done with the PLL removed from the
PCB. This requires the use of a clamp down fixture that may
not always be generally available. If no clamp down fixture is
available, then this procedure can be done by calibrating up
to the point where the DC blocking capacitor usually is, and
then adding a 0 ohm resistor back for the actual measure-
ment. Once that the network analyzer is calibrated, it is
necessary to ensure that the PLL is powered up. This can be
done by toggling the power down bits (RF_PD and IF_PD)
and observing that the current consumption indeed in-
creases when the bit is disabled. Sometimes it may be
necessary to apply a signal to the OSCin pin in order to
program the part. If this is necessary, disconnect the signal
once it is established that the part is powered up. It is useful
to know the input impedance of the PLL for the purposes of
debugging RF problems and designing matching networks.
Another use of knowing this parameter is make the trace
width on the PCB such that the input impedance of this trace
matches the real part of the input impedance of the PLL
frequency of operation. In general, it is good practice to keep
trace lengths short and make designs that are relatively
resistant to variations in the input impedance of the PLL.
L
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相關PDF資料
PDF描述
LMX2470SLEX 2.6 GHz Delta-Sigma Fractional-N PLL with 800 MHz Integer-N PLL
LMX2485 50 MHz - 3.0 GHz High Performance Delta-Sigma Low Power Dual PLLatinum⑩ Frequency Synthesizers with 800 MHz Integer PLL
LMX2485E 50 MHz - 3.0 GHz High Performance Delta-Sigma Low Power Dual PLLatinum⑩ Frequency Synthesizers with 800 MHz Integer PLL
LMX2485ESQ 50 MHz - 3.0 GHz High Performance Delta-Sigma Low Power Dual PLLatinum⑩ Frequency Synthesizers with 800 MHz Integer PLL
LMX2485ESQX 50 MHz - 3.0 GHz High Performance Delta-Sigma Low Power Dual PLLatinum⑩ Frequency Synthesizers with 800 MHz Integer PLL
相關代理商/技術參數(shù)
參數(shù)描述
LMX2470EVAL 功能描述:時鐘和定時器開發(fā)工具 LMX2470 EVAL BOARD RoHS:否 制造商:Texas Instruments 產(chǎn)品:Evaluation Modules 類型:Clock Conditioners 工具用于評估:LMK04100B 頻率:122.8 MHz 工作電源電壓:3.3 V
LMX2470SLEX 功能描述:鎖相環(huán) - PLL RoHS:否 制造商:Silicon Labs 類型:PLL Clock Multiplier 電路數(shù)量:1 最大輸入頻率:710 MHz 最小輸入頻率:0.002 MHz 輸出頻率范圍:0.002 MHz to 808 MHz 電源電壓-最大:3.63 V 電源電壓-最小:1.71 V 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝 / 箱體:QFN-36 封裝:Tray
LMX2470SLEX/NOPB 功能描述:鎖相環(huán) - PLL RoHS:否 制造商:Silicon Labs 類型:PLL Clock Multiplier 電路數(shù)量:1 最大輸入頻率:710 MHz 最小輸入頻率:0.002 MHz 輸出頻率范圍:0.002 MHz to 808 MHz 電源電壓-最大:3.63 V 電源電壓-最小:1.71 V 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝 / 箱體:QFN-36 封裝:Tray
LMX2471 制造商:NSC 制造商全稱:National Semiconductor 功能描述:3.6 GHz Delta-Sigma Fractional-N PLL with 1.7 GHz Integer-N PLL
LMX2471 WAF 制造商:Texas Instruments 功能描述: