Visjnoe
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Dear all,
I have some questions on the Hogge phase detector:
1. Is the requirement on the concurrent on-time of the UP/DOWN signals comparable to that of a standard three-state PFD (impact on reference spur, CP noise etc.)? I think the same ideas apply, independent of the type of PFD (strictly speaking of course, the Hogge phase detector is a PD and not a PFD)
2. Given the constraint the input frequency is very close to the VCO frequency (few ppm) can the Hogge PD be used in a PLL that in one mode has to generate a CLK signal from data (recover clock from data) and in another mode clean up an external CLK signal? Thus, the input to the PLL can be data or a CLK signal (same frequency): can Hogge serve both purposes (given the constraint of small frequency offset) or do we need to implement to PFD's: one, classical three-state and one Hogge?
Kind Regards
Peter
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