Datasheet

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DP83849I
8.2.28 Single Clock MII (SCMII) Transmit Timing
Note: Latency measurement is made from the X1 Rising edge to the first bit of symbol.
Parameter Description Notes Min Typ Max Units
T2.28.1 X1 Clock Period 25MHz Reference Clock 40 ns
T2.28.2 TXD[3:0], TX_EN Data Setup To X1 rising 4 ns
T2.28.3 TXD[3:0], TX_EN Data Hold From X1 rising 2 ns
T2.28.4 X1 Clock to PMD Output Pair
Latency (100Mb)
100BASE-TX mode 13 bits
TXD[3:0]
TX_EN
Valid Data
T2.28.2
T2.28.3
PMD Output Pair
Symbol
T2.28.4
X1
T2.28.1