mpc8378e Freescale Semiconductor, Inc, mpc8378e Datasheet - Page 30

• Manufacturer Part Number: mpc8378e
• Description: Powerquicc Ii Pro Processor Hardware Specifications
• Manufacturer: Freescale Semiconductor, Inc

Ethernet: Enhanced Three-Speed Ethernet (eTSEC)
8.3.2
Table 30
intended to be used with, and should not be clocked by, a spread spectrum clock source.
8.3.3
This section describes the MII transmit and receive AC timing specifications.
8.3.3.1
Table 31
30
At recommended operating conditions with LV
L1_SD_REF_CLK/_B reference clock cycle time
L1_SD_REF_CLK/_B rise/fall time (80%-20%)
L1_SD_REF_CLK/_B duty cycle (@50% L1_ n V
L1_SD_REF_CLK/_B cycle to cycle clock jitter (period
jitter)
L1_SD_REF_CLK/_B phase jitter peak-to-peak.
Deviation in edge location with respect to mean edge
location.
Note:
1
2
TX_CLK clock period 10 Mbps
TX_CLK clock period 100 Mbps
TX_CLK duty cycle
TX_CLK to MII data TXD[3:0], TX_ER, TX_EN delay
TX_CLK data clock rise (20%–80%)
TX_CLK data clock fall (80%–20%)
Note:
Both options provide serial interface bit rate of 1.25 Gbps. 8 ns only applies when 125 MHz SerDes1 clock frequency is
selected during POR.
Tolerance of ±100 ppm.
lists the AC timing specifications. Note that L1_SD_REF_CLK and L1_SD_REF_CLK are not
provides the MII transmit AC timing specifications.
AC Requirements for SGMII L1_SD_REF_CLK and L1_SD_REF_CLK
MII AC Timing Specifications
MII Transmit AC Timing Specifications
Parameter/Condition
Table 30. L1_SD_REF_CLK and L1_SD_REF_CLK AC Requirements
MPC8378E PowerQUICC II Pro Processor Hardware Specifications, Rev. 3
Parameter
Table 31. MII Transmit AC Timing Specifications
DD
of 3.3 V ± 5%.
100 MHz
125 MHz
DD
)
t
CK_RISE
Symbol
t
CK_REF
t
t
t
ck_dty
t
Symbol
MTXH/
CKPJ
CKCJ
t
MTKHDX
t
t
/t
t
t
MTXR
MTXF
MTX
MTX
CK_FALL
t
MTX
1
45%
Min
–50
—
—
—
Min
1.0
1.0
35
—
—
1
Typical
10
—
—
—
—
Typical
8
400
40
—
—
—
5
Freescale Semiconductor
55%
Max
100
50
—
1
Max
4.0
4.0
—
—
65
15
Unit
ns
ns
ps
ps
ps
Unit
Notes
ns
ns
ns
ns
ns
%
1, 2
—
—
—
—