LAN8810I-AKZE Datasheet, PDF (91/100 Pages) Microchip Technology – GMII 10/100/1000 Ethernet Transceiver with HP Auto-MDIX Support

5.5.5
GMII 10/100/1000 Ethernet Transceiver with HP Auto-MDIX Support
Datasheet
GMII Timing (1000BASE-T)
This section specifies the GMII interface transmit and receive timing. Please refer to Section 3.3, "GMII
Interface," on page 24 for additional details.
Note: All GMII timing specifications assume a point-to-point test circuit as defined in Section 35.4.2.2
of the IEEE 802.3-2005 specification.
GTXCLK
TXD[7:0],
TXEN, TXER
t_r
t_f
t_val t_hold
Figure 5.5 GMII Transmit Timing
t_clkp
t_clkh t_clkl
Table 5.14 GMII Transmit Timing Values
SYMBOL
f_gtxclk
DESCRIPTION
GTXCLK Frequency
t_clkp
GTXCLK period
t_clkh
GTXCLK high time
t_clkl
GTXCLK low time
t_val
TXD[7:0], TXEN, TXER setup time to rising
edge of GTXCLK
t_hold
TXD[7:0], TXEN, TXER hold time after rising
edge of GTXCLK
t_r
GTXCLK rise time
t_f
GTXCLK fall time
MIN
125 -
100ppm
7.5
2.5
2.5
2.0
MAX
125 +
100ppm
8.5
UNITS
MHz
NOTES
ns
Note 5.20
ns
ns
ns
0.0
ns
1
ns
Note 5.21
1
ns
Note 5.21
Note 5.20 Min/max limits are non-sustainable long term.
Note 5.21 t_r and t_f are measured from V_{IL_AC(Max)}=0.7V to V_{IH_AC(Min)}=1.9V.
SMSC LAN8810/LAN8810i
91
DATASHEET
Revision 1.0 (02-06-13)