lxt972a Intel Corporation, lxt972a Datasheet - Page 48

• Manufacturer Part Number: lxt972a
• Description: 3.3v Dual-speed Fast Ethernet Transceiver Datasheet
• Manufacturer: Intel Corporation

LXT972A — 3.3V Dual-Speed Fast Ethernet Transceiver Datasheet
48
TXD<3:0>, TX_EN, TX_ER setup to TX_CLK High
TXD<3:0>, TX_EN, TX_ER hold from TX_CLK High
TX_EN sampled to CRS asserted
TX_EN sampled to CRS de-asserted
TX_EN sampled to TPO out (Tx latency)
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
Figure 25. 100BASE-TX Transmit Timing - 4B Mode
Table 26. 100BASE-TX Transmit Timing Parameters
s or 10 ns.
TXD<3:0>
TXCLK
TX_EN
CRS
TPO
Parameter
0ns
t3
t5
t2
t1
Sym
t1
t2
t3
t4
t5
Min
5.3
12
20
24
0
-
4B Mode
Typ
–
–
–
–
–
1
t4
250ns
Max
5.7
24
28
–
–
Units
BT
BT
BT
ns
ns
2
Test Conditions
Datasheet
–
–
–
–
–
-