Comment by bee_rider | Hacker News Reader

Comment by bee_rider | Hacker News Reader

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> Trinary didn’t make any headway in the 20th century; binary’s direct mapping to the “on”/”off” states of electric current was just too effective, or seductive; but remember that electric current isn’t actually “on” or “off”. It has taken a ton of engineering to “simulate” those abstract states in real, physical circuits, especially as they have gotten smaller and smaller.

But, I think things are actually trending the other way, right? You just slam the voltage to “on” or “off” nowadays—as things get smaller, voltages get lower, and clock times get faster, it gets harder to resolve the tiny voltage differences.

Maybe you can slam to -1. OTOH, just using 2 bits instead of one... trit(?) seems easier.

Same reason the “close window” button is in the corner. Hitting a particular spot requires precision in 1 or 2 dimensions. Smacking into the boundary is easy.

The lower voltage helps reduce leakage and capacitance in the chip as the wires get closer together.

But it does argue against more states due to the benefits of just making 1 smaller if you can and packing things closer. Though maybe we are hitting the bottom with Dennard scaling being dead. Maybe we increase pitch and double state on parts of the chip, and then generations are measured by bits per angstrom.

Once we invented CMOS this problem pretty much went away. You can indeed just slam the transistor open and closed.

Well, until we scaled transistors down to the point where electrons quantum tunnel across the junction. Now they're leaky again.

Not quite. Leakage current in CMOS circuits became the dominant source of power consumption around the 90 nm and 65 nm nodes, long before quantum tunneling was a major factor, and often exceeded dynamic switching power. This led to the introduction of multiple threshold-voltage devices and body-biasing techniques to dynamically adjust Vt and curb static leakage.

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