General i/o pins – Altera PowerPlay Early Power Estimator User Manual
Page 29

Altera Corporation
3–15
May 2008
PowerPlay Early Power Estimator For Arria GX FPGAs
Using the PowerPlay Early Power Estimator
Figure 3–7. DSP Section in the PowerPlay Early Power Estimator
General I/O Pins
Arria GX devices feature programmable I/O pins that support a wide
range of industry I/O standards for increased design flexibility. The I/O
section in the PowerPlay Early Power Estimator spreadsheet allows you
to estimate the I/O pin power consumption based on the pin’s I/O
standards.
1
The PowerPlay Early Power Estimator spreadsheet assumes
you are using external termination resistors when you design
with I/O standards that recommend termination resistors (SSTL
and HSTL). If your design does not use external termination
resistors, you should choose the LVTTL I/O standard with the
same V
CCIO
and similar drive strength as the terminated I/O
standard. For example, if you are using the SSTL-2 class II I/O
standard without termination resistors (using a point-to-point
connection), you should select LVTTL/LVCMOS 2.5-V as your
I/O standard and 16mA as the Drive Strength in the PowerPlay
Early Power Estimator.
The power reported for I/O signals includes thermal and external I/O
power. The total thermal power is the sum of the thermal power
consumed by the device based on each power rail, for example:
thermal power = thermal P
INT
+ thermal P
PD
+ thermal P
IO
Figure 3–8
shows a graphical representation of the I/O power
consumption. The I
CCIO
rail power includes both the thermal P
IO
and the
external P
IO
.