Altera PowerPlay Early Power Estimator - Manual (Page 35)

Chapter 3: Using Cyclone III PowerPlay Early Power Estimator 3–23
Power Analysis
© June 2009 Altera Corporation PowerPlay Early Power Estimator User Guide for Cyclone III FPGAs
Table 3–10 describes the thermal analysis parameters in the PowerPlay Early Power
Estimator.
Power Supply Current (A)
The power supply current section provides the estimated current draw from all
power supplies. The I
CCINT
/I
CCA
/I
CCD
current is the supply current required from
V
CCINT
/V
CCA
/V
CCD
, respectively. The total I
CCIO
current is the supply current required
from all V
CCIO
power supplies. For estimates of I
CCIO
based on power supply, refer to the
I/O section of the PowerPlay Early Power Estimator.
Figure 3–19 shows the power supply current estimation. I
CCINT
, I
CCA
, I
CCD
, and I
CCIO
are
displayed.
Table 3–11 describes the parameters in the Power Supply Current section of the
PowerPlay Early Power Estimator.
Table 3–10. Thermal Analysis Section Information
Parameter Description
Junction Temp, T
J
(°C) This shows the device junction temperature estimated based on supplied thermal parameters.
The junction temperature is determined by dissipating the total thermal power through the top of
the chip and through the board (if selected). For detailed calculations used, click Details.

JA
Junction-Ambient This shows the junction-to-ambient thermal resistance between the device and ambient air 
(in °C/W).
This represents the increase in temperature between ambient and junction for every watt of
additional power dissipation.
Maximum Allowed T
A
(°C)
This shows a guideline for the maximum ambient temperature (in °C) that the device can be
subjected to without violating maximum junction temperature, based on the supplied cooling
solution and device temperature grade.
Figure 3–19. Power Supply Current in the PowerPlay Early Power Estimator
Table 3–11. Power Supply Current Information (Part 1 of 2)
Parameter Description
I
CCINT
This shows the total current drawn from the V
CCINT
supply (in A).
I
CCA
This shows the total current drawn from the V
CCA
supply (in A).