This is a breakout board for the very handy 16-Channel Analog/Digital Multiplexer/Demultiplexer CD74HC4067. This chip is like a rotary switch - it internally routes the common pin (COM in the schematic, SIG on the board) to one of 16 channel pins (CHANxx). https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2021-04-06 https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2022-05-18 https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2022-11-21 https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2022-12-01 https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2023-02-27 https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2023-03-07 https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2023-03-13 https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2023-03-14 https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2023-03-15 https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2023-03-16 https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2023-08-11 https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2023-08-18 https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2023-08-23 https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2024-07-10 https://elecena.pl/product/17498617/sparkfun-analog-digital-mux-breakout-cd74hc4067 2024-08-04