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Altera_Forum
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13 years ago

StratixIV GX and SFP

I want use GXB_RX and GXB_TX link to the SFP. The GXB_RX and GXB_TX are LVDS levels. The SFP is LVPECL or CML levels. How to link them? In the StratixIV GT board of Altera, they just li...
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Altera_Forum
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11 years ago

VCCH_GXB[L,R] can be connected to a 1.4 V or 1.5 V linear or low noise switching regulator.

Connect these pins to 1.4 V if the transmitter channel data rate is > 6.5 Gbps.

Connect these pins to 1.5 V if the transmitter channel data rate is ≤ 6.5 Gbps.

For data rates ≤ 6.5 Gbps where VCCH_GXB is 1.5 V these pins may be sourced from the same regulator as VCCPT with a proper isolation filter.

For data rates ≤ 6.5 Gbps it is possible to use 1.4 V from a source that is already utilized on the board as long as VCCH_GXB is properly isolated from the other supply.

Decoupling for these pins depends on the design decoupling requirements of the specific board design.