PCX755BVZFU300LE Atmel, PCX755BVZFU300LE Datasheet - Page 42

• Manufacturer Part Number: PCX755BVZFU300LE
• Description: IC MPU 32BIT 300MHZ 360PBGA
• Manufacturer: Atmel

Specifications of PCX755BVZFU300LE

• Processor Type: PowerPC 32-Bit RISC
• Speed: 300MHz
• Voltage: 2V
• Mounting Type: Surface Mount
• Package / Case: 360-PBGA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Features: -

10.3
10.4
10.5
42
Decoupling Recommendations
Connection Recommendations
Output Buffer DC Impedance
PC755/745
Due to the PC755’s dynamic power management feature, large address and data buses, and
high operating frequencies, the PC755 can generate transient power surges and high frequency
noise in its power supply, especially while driving large capacitive loads. This noise must be pre-
vented from reaching other components in the PC755 system, and the PC755 itself requires a
clean, tightly regulated source of power. Therefore, it is recommended that the system designer
place at least one decoupling capacitor at each
also recommended that these decoupling capacitors receive their power from separate
(L2)OV
These capacitors should have a value of 0.01 µF or 0.1 µF. Only ceramic SMT (surface mount
technology) capacitors should be used to minimize lead inductance, preferably 0508 or 0603 ori-
entations where connections are made along the length of the part.
In addition, it is recommended that there be several bulk storage capacitors distributed around
the PCB, feeding the
chip capacitors. These bulk capacitors should have a low ESR (equivalent series resistance) rat-
ing to ensure the quick response time necessary. They should also be connected to the power
and ground planes through two vias to minimize inductance. Suggested bulk capacitors – 100-
330 µF (AVX TPS tantalum or Sanyo OSCON).
To ensure reliable operation, it is highly recommended to connect unused inputs to an appropri-
ate signal level through a resistor. Unused active low inputs should be tied to O
active high inputs should be connected to GND. All NC (no-connect) signals must remain
unconnected.
Power and ground connections must be made to all external
of the PC755.
The PC755 60x and L2 I/O drivers are characterized over process, voltage, and temperature. To
measure Z
value of each resistor is varied until the pad voltage is (L2)O
The output impedance is the average of two components, the resistances of the pull-up and pull-
down devices. When Data is held low, SW2 is closed (SW1 is open), and R
voltage at the pad equals (L2)O
When Data is held high, SW1 is closed (SW2 is open), and R
pad equals (L2)O
NO TAG describes the driver impedance measurement circuit described above.
DD
and GND power planes in the PCB, utilizing short traces to minimize inductance.
0
, an external resistor is connected from the chip pad to (L2)OV
V
DD
/2. R
V
DD
, L2O
P
then becomes the resistance of the pull-up devices.
V
V
DD
DD
, and OV vplanes, to enable quick recharging of the smaller
/2. R
N
then becomes the resistance of the pull-down devices.
V
DD
, O
V
DD
, and L2OV
V
P
DD
V
is trimmed until the voltage at the
DD
/2 (See
, O
V
DD
DD
Figure 10-4 on page
, L2O
pin of the PC755. It is
DD
N
V
is trimmed until the
or GND. Then, the
DD
, and GND pins
2138G–HIREL–05/06
V
DD
. Unused
V
43).
DD
,