what does a(n) (16-Bit I/O) expander do?


what does a(n) (16-Bit I/O) expander do?

In: Technology

There are two primary methods of doing digital communications over a wired bus: serial and parallel. With a serial bus, data bits are sent on a small number of wires (as few as 1 or 2) one after the other…in series. This is nice because there aren’t a lot of wires.

With parallel busses, there are many data wires…4,8,16, etc. Data is sent in bunches over all the wires at the same time. Of course, it is also serial because after one data bunch is sent, then another one is, then another. Obviously, there are a lot more wires to deal with, but you can also transmit a lot more data bits per second. (Although some of the fastest busses are serial. They make up for the lack of parallelism by sending at a very very fast bit rate that parallel busses have a hard time doing due to interference between bits.)

And as one might guess, a 16 bit I/O expander translates a serial bus (such as I^2 C) into a 16 bit wide parallel bus. This doesn’t necessarily make the data rate any faster than it was originally, it is just a way of mating up the two different kinds of technology.