Za zunanjo uro vir, ki PAD je najboljša izbira?

[Jerry Yau]

Spoštovani,
Followings so TSMC 0,35 I / O PAD, rad bi vedeli, kateri od najboljša izbira za zunanjo ure signal, ki ga 48MHz Oscillator:
PDCHxSM: Zelo Fast Schmitt Trigger Non-Inverting Clock Input Pad, 5V-Toleranten, Connecting VDD5V Power Ring
PDCHxSZ: High Drive, Schmitt Trigger Input Clock Pad, 5V, Toleranten
PDCHxTZ: High Drive, TTL Clock Input Pad, 5V, Toleranten
PDCxTZ: Zelo Fast TTL Non-Inverting Clock Driver, 5V, Toleranten
PDIM: Input Pad, 5V-Toleranten, Connecting VDD5V Power Ring
PDISM: Schmitt Trigger Input Pad, 5V-Toleranten, Connecting VDD5V Power

PDCHxSM, PDCHxSZ, PDCHxTZ potreba 2 PAD okna.Drugo Potrebujem samo en PAD okna.
In je čip PAD meja

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