Altera PowerPlay Early Power Estimator User Manual
Page 34
Column Heading
Description
I/O Standard
Select the I/O standard used for the input, output, or
bidirectional pins in this module from the drop-down list.
The calculated I/O power varies based on the I/O standard.
For I/O standards that recommend termination (SSTL and
HSTL), the PowerPlay EPE spreadsheet assumes you are
using external termination resistors. If you are not using
external termination resistors, choose the LVTTL/LVCMOS
I/O standard with the same voltage and current strength as
the terminated I/O standard.
To view all the I/O standards in the drop-down list, use the
scroll bar.
Input Termination
Select the input termination (on-chip parallel termination
[R
T
OCT] or on-chip differential termination [R
D
OCT])
setting implemented for the input and bidirectional pins in
this module.
Current Strength/ Output Termination
Select the current strength or output termination (on-chip
serial termination [R
S
OCT]) implemented for the output
and bidirectional pins in this module.
Current strength and output termination are mutually
exclusive.
Slew Rate
Select the slew rate setting for the output and bidirectional
pins in this module. Using a lower slew rate setting helps to
reduce switching noise but may increase delay.
V
OD
Setting
Select the V
OD
for the output and bidirectional pins in this
module. If you use a lower voltage, it helps to reduce static
power.
Pre-Emphasis Setting
Select the pre-emphasis setting for output and bidirectional
pins in this module. Disable the pre-emphasis will reduce
dynamic power.
#Input Pins
Enter the number of input pins used in this module.
Consider a differential pin pair as one pin.
#Output Pins
Enter the number of output pins used in this module.
Consider a differential pin pair as one pin.
#Bidir Pins
Enter the number of bidirectional pins used in this module.
When you enable the output enable signal, the I/O pin is
treated as an output. When you disable the output enable
signal, the I/O pin is treated as an input.
An I/O configured as bidirectional but used only as an
output consumes more power than an I/O configured as
output-only, due to the toggling of the input buffer every
time the output buffer toggles (they share a common pin).
3-24
I/O Worksheet
UG-01070
2015.01.20
Altera Corporation
PowerPlay Early Power Estimator Worksheets