Altera PowerPlay Early Power Estimator - Manual (Page 22)

3–10 Chapter 3: Using Cyclone III PowerPlay Early Power Estimator
PowerPlay Early Power Estimator Inputs
PowerPlay Early Power Estimator User Guide for Cyclone III FPGAs © June 2009 Altera Corporation
# of Instances Enter the number of DSP block instances that have the same configuration, clock frequency,
toggle percentage, and register usage. This value is independent of the number of dedicated
DSP blocks being used.
For example, it is possible to use two 9 × 9 simple multipliers that would all be implemented in
the same DSP block in a Cyclone III device. In this case, the number of instances would be
two.
Clock Freq (MHz) Enter the clock frequency for the module in MHz. This value is limited by the maximum
frequency specification for the device family.
Toggle % Enter the average percentage of DSP data outputs toggling on each clock cycle. The toggle
percentage ranges from 0 to 50%. Typically the toggle percentage is 12.5%. For a more
conservative power estimate, you can use a higher toggle percentage.
A toggle rate of 50% corresponds to a randomly changing signal (since half the time the signal
changes from a 0

0 or 1

1). This is considered the highest meaningful toggle rate for a
DSP block.
Reg Inputs? Select whether the input to the dedicated DSP block or multiplier block is registered using the
dedicated input registers. If the dedicated input registers in the DSP or multiplier block are
being used, select Yes. If the inputs are registered using registers in LEs, select No.
Reg Outputs? Select whether the outputs of the dedicated DSP block or multiplier block are registered using
the dedicated output registers. If the dedicated output registers in the DSP or multiplier block
are being used, select Yes. If the outputs are registered using registers in LEs, select No.
Pipe-lined? Select whether the dedicated DSP block is pipelined.
Thermal Power (W),
Routing This shows the power dissipation due to estimated routing (in W).
Routing power is highly dependent on placement and routing, which is itself a function of
design complexity. The values shown are representative of routing power based on
experimentation on over 100 customer designs.
Use the Quartus II PowerPlay Power Analyzer for detailed analysis based on the routing used
in your design. This value is automatically calculated.
Thermal Power (W), Block This shows the estimated power consumed by the DSP blocks (in W). This value is
automatically calculated.
Thermal Power (W), Total This shows the estimated power (in W), based on the inputs you entered. It is the total power
consumed by DSP blocks and is equal to the routing power and the block power. This value is
automatically calculated.
User Comments Enter any comments. This is an optional entry.
Table 3–4. DSP and Multiplier Section Information (Part 2 of 2)
Parameters Description