LMX2582: RFOUT caps

Nandini Muralidharan

Part Number: LMX2582
Other Parts Discussed in Thread: LMX1214, ADC12DL3200EVM

Tool/software:

Hi,

Output of LMX2582 is set to 1800MHz which will be the input frequency for ADC12DL2500ACF and LMX1214

What would be the suggested capacitor value at the RFOUT clock lines? Currently I am keeping 100pF. But I am seeing ADC12DL3200EVM uses 4700pF for the RFOUT of same PLL.

Thanks

over 1 year ago

0 Noel Fung over 1 year ago

TI__Guru** 112770 points

Hi Nandini,

I think you should ask the ADC team for the suggestion. 1.8GHz is divided down frequency, the waveform is square wave. Slew rate or harmonics after the capacitor may be different with 100pF and 4.7nF capacitor. I am not sure what is the requirement form ADC.

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LMX2582: RFOUT caps