mpc8569e Freescale Semiconductor, Inc, mpc8569e Datasheet - Page 64

• Manufacturer Part Number: mpc8569e
• Description: Mpc8569e Powerquicc Iii Integrated Processor Hardware Specifications
• Manufacturer: Freescale Semiconductor, Inc

Ethernet Interface
64
For recommended operating conditions, see
Duty cycle for Gigabit
Rise time (20%–80%)
Fall time (20%–80%)
Notes:
1. In general, the clock reference symbol representation for this section is based on the symbols RGT to represent RGMII and
2. This implies that PC board design will require clocks to be routed such that an additional trace delay of greater than 1.5 ns is
3. For 10 and 100 Mbps, t
4. Duty cycle may be stretched/shrunk during speed changes or while transitioning to a received packet's clock domains as long
5. The frequency of RX_CLK should not exceed the frequency of gigabit ethernet reference clock by more than 300 ppm.
6. System/board must be designed to ensure the input requirement to the device is achieved. Proper device operation is
RTBI timing. For example, the subscript of t
(R) and fall (F) times follows the clock symbol that is being represented. For symbols representing skews, the subscript is
skew (SK) followed by the clock that is being skewed (RGT).
added to the associated clock signal. Many PHY vendors already incorporate the necessary delay inside their chip. If so,
additional PCB delay is probably not needed.
as the minimum duty cycle is not violated and stretching occurs for no more than three t
between.
guaranteed for inputs meeting this requirement by design, simulation, characterization, or functional testing.
MPC8569E PowerQUICC III Integrated Processor Hardware Specifications, Rev. 0
Parameter
Table 35. RGMII and RTBI AC Timing Specifications (continued)
RGT
scales to 400 ns ± 40 ns and 40 ns ± 4 ns, respectively.
Table 3
RGT
represents the TBI (T) receive (RX) clock. Note also that the notation for rise
t
RGTH
Symbol
t
t
RGTR
RGTF
/t
RGT
1
Min
45
—
—
Typ
50
—
—
RGT
of the lowest speed transitioned
Max
1.75
1.75
55
Freescale Semiconductor
Unit
ns
ns
%
Notes
6
6
6