mpc8640 Freescale Semiconductor, Inc, mpc8640 Datasheet - Page 121

no-image

mpc8640

Manufacturer Part Number
mpc8640
Description
Integrated Host Processor
Manufacturer
Freescale Semiconductor, Inc
Datasheet
SENSEV
Likewise, AV
The mechanical drawing for the single core device is located in
the MPC8640
For other pin pull-up or pull-down recommendations of signals, please see
20.7
The MPC8640 drivers are characterized over process, voltage, and temperature. For all buses, the driver
is a push-pull single-ended driver type (open drain for I
To measure Z
or GND. Then, the value of each resistor is varied until the pad voltage is OV
output impedance is the average of two components, the resistances of the pull-up and pull-down devices.
When data is held high, SW1 is closed (SW2 is open) and R
OV
other in value. Then, Z
Table 73
nominal OV
Freescale Semiconductor
DD
/2. R
summarizes the signal impedance targets. The driver impedances are targeted at minimum V
SS
Output Buffer DC Impedance
P
_Core1 and needs to be connected to ground with a weak (2–10 k
DD
Note: Nominal supply voltages. See
then becomes the resistance of the pull-up devices. R
DD
0
FC-CBGA.”
Impedance
MPC8640 and MPC8640D Integrated Host Processor Hardware Specifications, Rev. 3
for the single-ended drivers, an external resistor is connected from the chip pad to OV
, 105 °C.
_Core1 needs to be pulled to ground as shown in
R
R
N
P
0
= (R
P
Configuration, Power
+ R
Figure 66. Driver Impedance Measurement
DUART, Control,
Data
Management
N
Table 73. Impedance Characteristics
43 Target
43 Target
) ÷ 2.
Table
1, T
j
= 105 °C.
25 Target
25 Target
Express
2
PCI
C).
Pad
P
R
R
is trimmed until the voltage at the pad equals
OV
OGND
N
P
Section 16.2, “Mechanical Dimensions of
DD
DDR DRAM
P
20 Target
20 Target
Figure
and R
SW2
SW1
N
64.
are designed to be close to each
Section 17, “Signal
Symbol
Ω)
DD
Z
Z
pull down resistor.
/2 (see
0
0
System Design Information
Unit
Figure
W
W
66). The
Listings.”
DD
DD
121
,

Related parts for mpc8640