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HMC1033开发板的外部时钟如何输入

Dear:
手册中这样写:
"The HMC1033/HMC1035 evaluation board includes a precision PLL which generates a 50 MHz
clock locked to an externally supplied 10 MHz reference. The PLL design is an HMC1031 phase/
frequency detector, passive loop filter and a low noise 50 MHz VCXO. The PLL is normally, or
default upon shipping, set to lock on to a 10 MHz reference feed into “REF IN”. A 5 MHz input
reference can be used if D1, D0 is reconfigured to “1,1”, or 50 MHz if D1, D0 is reconfigured to
“0,1”. The “REF IN” would normally have a +/-50 ppm tolerance which falls within the VCXO pull
range. Although not recommended, the HMC1033/HMC1035 Eval Board can be operated without
supplying an external reference, and the PLL will pull the VCXO to about 49.992 MHz, or 180
ppm low. Alternatively, an external reference can be feed into the HMC1033/HMC1035 evaluation
board which requires removing C44,C35, R32 and J6, the TPLL/TCXO Jumper, and placing a 0
Ohm resistor in the R20 and R36 locations. See Evaluation PCB Schematic for more details. The
HMC1032/HMC1034 eval boards have a 50 MHz crystal oscillator and do not require an external
source."


如果我需要加一个外部的10MHz标准铯钟信号,那么我直接接到ref in端口,还是需要移走C44,C35, R32 and J6, the TPLL/TCXO Jumper, and placing a 0 Ohm resistor in the R20 and R36 locations. 另外反向和同相输出有什么信号上的区别吗