Revision 1.23 - January 28, 2009
PPC405EX – PowerPC 405EX Embedded Processor
Data Sheet
Pin Group List
The following table provides a summary of the number of package pins (balls) associated with each functional
interface group.
Table 5. Pin Groups
Group
Total Signal Pins
VDD
No. of Pins
246
17
20
6
OVDD
EOVDD
SVDD
10
71
7
GND
AVDD
AHVDD
SAVDD
2
1
1
SAGND
EAVDD
1
EAGND
AGND
1
4
Total Power Pins
Reserved
141
1
Total Pins
388
In the table “Signal Functional Description” on page 39, each external signal is listed along with a short description
of the signal function. Active-low signals (for example, Halt) are marked with an overline. See the preceding table,
“Signals Listed Alphabetically” on page 18, for the pin (ball) number to which each signal is assigned.
Shared Pins
Some signals are shared on the same package pin so that the pin can be used for different functions. In most
cases, the signal names shown in this table are not accompanied by signal names that might share the same pin.
If you need to know what, if any, signals are shared with a particular signal, look up the name in “Signals Listed
Alphabetically” on page 18. It is expected that in any single application a particular pin will always be programmed
to serve the same function. The flexibility of sharing allows a single chip to offer a richer pin selection than would
otherwise be possible.
Initialization Strapping
One group of pins is used as strapped inputs during system reset. These pins function as strapped inputs only
during reset and are used for other functions during normal operation (see “Initialization” on page 71). Note that the
use of these pins for strapping is not considered multiplexing since the strapping function is not programmable.
Pull-Up and Pull-Down Resistors
Pull-up and pull-down resistors are used for strapping during reset and to retain unused or undriven inputs in an
appropriate state. The recommended pull-up value of 3kΩ to +3.3V and pull-down value of 1kΩ to GND, applies
only to individually terminated signals. To prevent possible damage to the device, I/Os capable of becoming
outputs must never be tied together and terminated through a common resistor.
If your system-level test methodology permits, input-only signals can be connected together and terminated
through either a common resistor or directly to +3.3V or GND. When a resistor is used, its value must ensure that
the grouped I/Os reach a valid logical zero or logical one state when accounting for the total input current into the
PPC405EX.
38
AMCC Proprietary