Andrey (andrey.semashev.delete@this.gmail.com) on November 21, 2022 4:23 am wrote:
> This will probably be a naive and silly question, but I'm curious.
>
> Assuming that a logical one is represented with a higher voltage than a logical zero in the IC,
> is it fair to say that ones are more expensive to process in terms of power and heat? That is,
> if it takes more energy to charge a DRAM or SRAM cell to a level of one (in case of DRAM - also
> to refresh it), if it takes more voltage to transfer the signal along the traces, if this voltage
> makes more heat in the transistors implementing a logical circuit within the IC, thus causing
> more leakage current, wouldn't it be more expensive? I wonder if someone tested this.
>
> If there is a measurable difference, wouldn't it make sense to account for that when designing the ICs and
> writing software? On the hardware level, it might make sense to process negated signals or a mixture of positive
> and negated signals to reduce the number of "ones" or at least make them statistically closer to "zeros" so
> to reduce the possible power consumption spikes. In software, it would make sense to prefer zero or power-of-two
> representations of data more often. Of course, it is not possible to have a useful machine (both in hardware
> and software) processing only zeros, but some difference could be made. Or could it?
>

The answer is perhaps surprisingly not that simple, as it varies with what is being implemented and in what technology that implementation is realized in.

For CMOS, transistors come in complementary pairs, reducing both switching times and dynamic power use - ideal power is only consumed when signals change, equilibrium is free of charge (sorry for the clumsy pun).

I write "ideal power" as they can not fabricate perfect superconducting logic at manageable temperatures yet|ever - there is a lot of resistance and leakage involved in addition to the required switching energy.