mpc8641 Freescale Semiconductor, Inc, mpc8641 Datasheet - Page 60

• Manufacturer Part Number: mpc8641
• Description: Integrated Host Processor Hardware Specifications
• Manufacturer: Freescale Semiconductor, Inc

High-Speed Serial Interfaces (HSSI)
60
4. Differential Peak Voltage, V
5. Differential Peak-to-Peak, V
6. Differential Waveform
7. Common Mode Voltage, V
two complimentary input voltages: V
negative.
each range from A – B to –(A – B) Volts, the peak-to-peak value of the differential transmitter
output signal or the differential receiver input signal is defined as Differential Peak-to-Peak
Voltage, V
amplitude, or twice of the differential peak. For example, the output differential peak-peak voltage
can also be calculated as V
of a balanced interchange circuit and ground. In this example, for SerDes output, V
(V
output voltages within a differential pair. In a system, the common mode voltage may often differ
from one component’s output to the other’s input. Sometimes, it may be even different between the
receiver input and driver output circuits within the same component. It is also referred as the DC
offset in some occasion.
The Differential Input Voltage (or Swing) of the receiver, V
The peak value of the differential transmitter output signal or the differential receiver input signal
Since the differential output signal of the transmitter and the differential input signal of the receiver
The differential waveform is constructed by subtracting the inverting signal (SDn_TX, for
The Common Mode Voltage is equal to one half of the sum of the voltages between each conductor
is defined as Differential Peak Voltage, V
example) from the non-inverting signal (SDn_TX, for example) within a differential pair. There is
only one signal trace curve in a differential waveform. The voltage represented in the differential
waveform is not referenced to ground. Refer to
A Volts
B Volts
SDn_TX
MPC8641 and MPC8641D Integrated Host Processor Hardware Specifications, Rev. 2
+ V
DIFFp-p
Figure 38. Differential Voltage Definitions for Transmitter or Receiver
SDn_TX
SD n _TX or
SD n _RX
SD n _TX or
SD n _RX
= 2*V
)/2 = (A + B) / 2, which is the arithmetic mean of the two complimentary
DIFFp
TX-DIFFp-p
Differential Peak-Peak Voltage, VDIFFpp = 2*VDIFFp (not shown)
cm
DIFFp
= 2 * |(A – B)| Volts, which is twice of differential swing in
DIFFp-p
Differential Swing, VID or VOD = A - B
Differential Peak Voltage, VDIFFp = |A - B|
SDn_RX
= 2*|V
DIFFp
OD
– V
Figure 47
= |A – B| Volts.
|.
SDn_RX.
The V
as an example for differential waveform.
ID
, is defined as the difference of the
ID
value can be either positive or
Freescale Semiconductor
V
cm
= (A + B) / 2
cm_out
=