Ethernet: Enhanced Three-Speed Ethernet (eTSEC)
Table 21. DUART DC Electrical Characteristics (continued)
High-level output voltage,
I
OH
= –100
μA
Low-level output voltage,
I
OL
= 100
μA
Input current,
(0 V
≤V
IN
≤
OV
DD
)
V
OH
V
OL
I
IN
OV
DD
– 0.2
—
—
—
0.2
±30
V
V
μA
Note:
• The symbol V
IN
, in this case, represents the OV
IN
symbol referenced in
7.2
DUART AC Electrical Specifications
Table 22. DUART AC Timing Specifications
Parameter
Value
256
> 1,000,000
16
Unit
baud
baud
—
Notes
—
provides the AC timing parameters for the DUART interface of the device.
Minimum baud rate
Maximum baud rate
Oversample rate
Notes:
1
Actual attainable baud rate will be limited by the latency of interrupt processing.
2
The middle of a start bit is detected as the 8
th
sampled 0 after the 1-to-0 transition of the start bit. Subsequent bit values are
sampled each 16
th
sample.
8
Ethernet: Enhanced Three-Speed Ethernet (eTSEC)
This section provides the AC and DC electrical characteristics for the enhanced three-speed Ethernet
controller.
8.1
SGMII Interface Electrical Characteristics
Each SGMII port features a 4-wire AC-coupled serial link from the dedicated SerDes1 interface of the
MPC8378E as shown in
where C
TX
is the external (on board) AC-coupled capacitor. Each output
pin of the SerDes transmitter differential pair features 50-Ω output impedance. Each input of the SerDes
receiver differential pair features 50-Ω on-die termination to SGND_SRDSn (xcorevss). The reference
circuit of the SerDes transmitter and receiver is shown in
When an eTSEC port is configured to operate in SGMII mode, the parallel interface’s output signals of
this eTSEC port can be left floating. Also, when operating in SGMII mode, the eTSEC EC_GTX_CLK125
MPC8378E PowerQUICC
™
II Pro Processor Hardware Specifications, Rev. 2
22
Freescale Semiconductor
FREESCALE [ FREESCALE SEMICONDUCTOR, INC ]
