LXT971A 3.3V Dual-Speed Fast Ethernet Transceiver
Figure 31. 100BASE-FX Transmit Timing
0ns
250ns
t1
TXCLK
TX_EN
t2
TXD<3:0>
t5
TPFO
t3
t4
CRS
Table 32. 100BASE-FX Transmit Timing Parameters
1
Parameter
Symbol
Min
Typ
Max
Units2
Test Conditions
TXD<3:0>, TX_EN, TX_ER setup to
TX_CLK High
t1
12
–
–
ns
–
TXD<3:0>, TX_EN, TX_ER hold from
TX_CLK High
t2
0
–
–
ns
–
TX_EN sampled to CRS asserted
TX_EN sampled to CRS de-asserted
t3
t4
17
22
–
–
20
24
BT
BT
–
–
TX_EN sampled to TPFO out (Tx
latency)
t5
5
–
5.3
BT
–
1. Typical values are at 25 °C and are for design aid only; not guaranteed and not subject to production
testing.
2. BT is the duration of one bit as transferred to and from the MAC and is the reciprocal of the bit rate.
100BASE-T bit time = 10-8 s or 10 ns.
64
Datasheet
Document #: 249414
Revision #: 002
Rev. Date: August 7, 2002
INTEL [ INTEL ]
