I want to get a quick look at the power consumption of one block.
--use RTL Compiler generate netlist(after syn) and sdf
--run gate sim with or without sdf annotated, get VCD
--use netlist and VCD in ETS, get power consumption
I found the power consumption get form VCD without sdf annotated is much greater than with sdf annotated.
This makes me confuse. I think the power with sdf annotated should be bigger. Can anyone help to explain this?
I found there is only one difference with the log (the value changes got from vcd).
without sdf annotated:
With this vcd command, 12005021 value changes and 1e-06 secondsimulation time were counted for power consumption calculation.
Filename (activity) :../in/ad9651_datapath_top_gate.vcd Names in file that matched to design : 234754/352833 Annotation coverage for this file : 54305/54305 = 100%
Activity annotation summary: Primary Inputs : 89/89 = 100% Flop outputs : 8172/8172 = 100% Memory/Macro outputs : 0/0 = 0% Tristate outputs : 0/0 = 0% Total Nets : 54305/54305 = 100%
with sdf annotated:
With this vcd command, 6867391 value changes and 1e-06 secondsimulation time were counted for power consumption calculation.
not sure what you are trying to compare. Is it
gates + activity(RC) vs. gates + SDF + activity(ETS) ?
The first thing I notice is that your annotation is different yet you are using the same netlist. The SDF should not affect your toggle annotation as far as I can tell hence I would focus on understandig that first. Obviously until your annotation lines up, the rest of the numbers do not have much of a chance. Same netlist and same activity information should produce the same annotation regardless of tools or additional files read. Then start peeling the onion on power numbers