I was reading a paper on "LOW-POWER DIGIT-SERIAL MULTIPLIER" And I came accross a problem of how they measured the power dissipated in the Multiplier which they have designed. It said on a paper that,they are using HEAT:Hierarchical Energy Analysis Tool,which is based on SPICE. I discussed with my Prof about this,but he adviced me not to use a HSPICE (which is available in our Uni) because a Multiplier is too big a circuit to use HSPICE. My question is how to Am I going to measure power dissipated in a digital circuit(in this case a Multiplier)

Thanks in advance, Chris