eldo_user

Setting Up An Analysis
Viewing Power Analysis Results Example
process nodes tend to make these problems worse. The power supply voltages tend to decrease,
and the leakage currents tend to increase exponentially at each new node. This means the
monitoring of current variables (that relate directly to power) is as important, if not more, than
the monitoring of voltages. Entire circuits are dedicated to the sole function of power
management, which means managing the complex sequences of powering up and powering
down multi-chip systems, or SOCs, that operate with 10 or 20 different power supply levels (to
save every microWatt possible).
Tip
See “.POWER_ANALYSIS” in the Eldo Reference Manual and “Analyzing Power
Consumption” in the EZwave User’s and Reference Manual.
Viewing Power Analysis Results Example
This example shows the power analysis of a simple circuit.
Prerequisites
• A netlist with a .POWER_ANALYSIS command specified, for example:
*Power Analysis example
.subckt bottom bottom_in
Rbottom1 bottom_in 0 100
Rbottom2 bottom_in 0 100
.ends bottom
.subckt top top_in
Xbottom top_in bottom
Xmiddle top_in bottom
Rmiddle top_in 0 100
.ends top
Vdd in 0 pwl ( 0 0 1u 0 2u 1 8u 1 10u 0)
Xtop in top
Rload in 0 100
.tran 15u 15u
.option eps=1e-4 nocatmx
.power_analysis
+ visible_columns=sum,type,max,avg
.probe tran v(in)
.end
• The power analysis results are stored in the waveform database folder named
POWER_TRAN.
Procedure
1. Run Eldo on a netlist with a .POWER_ANALYSIS command specified.
2. Open the waveform database containing the power analysis results.
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Eldo® User's Manual, 15.3