17–4
Chapter 17: Understanding and Evaluating Power in MAX II Devices
PowerPlay Early Power Estimator Inputs
Input Parameters
Different MAX II devices consume different amounts of power for the same design.
The larger the device, the more power it consumes because of a larger clock tree. In
the Main section, you can enter the following parameters for the device and design:
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■
■
■
■
■
■
Device
Package
Temperature grade
Power characteristics
V
CCINT
supply
Ambient temperature
Airflow
shows the Input Parameter section in the PowerPlay Early Power
Estimator spreadsheet.
Figure 17–3.
Input Parameter Section
describes the values that must be specified in the Input Parameter section
of the PowerPlay Early Power Estimator spreadsheet.
Table 17–1.
Input Parameter Section Information (Part 1 of 2)
Input Parameter
Device
Description
Select your MAX II device. Larger devices have slightly higher clock dynamic power. MAX IIZ
devices have the lowest I
CCINT
compared to the MAX II and MAX IIG devices because MAX IIZ
devices have optimized circuitry to reduce I
CCINT
. Compared to MAX II devices, MAX IIG devices use
less power because they do not use the on-chip voltage regulator.
Select the package that will be used. Larger packages provide a larger cooling surface and more
contact points to the circuit board, leading to lower thermal resistance. Package selection does not
affect power consumption.
Commercial devices have a maximum junction operating temperature of 85°C. Industrial devices
offer 100°C operation while the MAX II automotive-grade devices can operate up to 125°C. This
field affects the maximum junction temperature used in thermal calculations.
For MAX IIZ devices, you can select either typical or maximum power characteristics for the power
estimation. The power characteristics are based on typical and theoretical worst-case silicon
process.
Maximum
should be used for thermal design, while
Typical
gives you the estimation of
the average use of the devices.
Package
Temperature Grade
Power Characteristics
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