
MPC8641 and MPC8641D Integrated Host Processor Hardware Specifications, Rev. 0
Freescale Semiconductor
37
Ethernet: Enhanced Three-Speed Ethernet (eTSEC), MII Management
Figure 16 shows the TBI transmit AC timing diagram.
Figure 16. TBI Transmit AC Timing Diagram
8.2.4.2
TBI Receive AC Timing Specifications
Table 33 provides the TBI receive AC timing specifications.
Table 33. TBI Receive AC Timing Specifications
At recommended operating conditions with L/TVDD of 3.3 V ± 5% and 2.5 V ± 5%.
Parameter/Condition
Symbol 1
Min
Typ
Max
Unit
PMA_RX_CLK[0:1] clock period
tTRX
3
16.0
ns
PMA_RX_CLK[0:1] skew
tSKTRX
7.5
—
8.5
ns
PMA_RX_CLK[0:1] duty cycle
tTRXH/tTRX
40
—
60
%
RCG[9:0] setup time to rising PMA_RX_CLK
tTRDVKH
2.5
—
ns
RCG[9:0] hold time to rising PMA_RX_CLK
tTRDXKH
1.5
—
ns
PMA_RX_CLK[0:1] clock rise time (20%-80%)
tTRXR
2
0.7
—
2.4
ns
PMA_RX_CLK[0:1] clock fall time (80%-20%)
tTRXF
2
0.7
—
2.4
ns
Note:
1. The symbols used for timing specifications herein follow the pattern of t(first two letters of functional block)(signal)(state)
(reference)(state) for inputs and t(first two letters of functional block)(reference)(state)(signal)(state) for outputs. For example,
tTRDVKH symbolizes TBI receive timing (TR) with respect to the time data input signals (D) reach the valid state (V)
relative to the tTRX clock reference (K) going to the high (H) state or setup time. Also, tTRDXKH symbolizes TBI
receive timing (TR) with respect to the time data input signals (D) went invalid (X) relative to the tTRX clock reference
(K) going to the high (H) state. Note that, in general, the clock reference symbol representation is based on three
letters representing the clock of a particular functional. For example, the subscript of tTRX represents the TBI (T)
receive (RX) clock. For rise and fall times, the latter convention is used with the appropriate letter: R (rise) or F (fall).
For symbols representing skews, the subscript is skew (SK) followed by the clock that is being skewed (TRX).
2. Guaranteed by design.
3. ±100 ppm tolerance on PMA_RX_CLK[0:1] frequency
GTX_CLK
TCG[9:0]
tTTXR
tTTX
tTTXH
tTTXR
tTTXF
tTTKHDV
tTTKHDX
tTTXF