This is a breakout board for the very handy 16-Channel Analog/Digital Multiplexer/Demultiplexer CD74HC4067. This chip can be used to connect 16 analog sources (like sensors) to 5 pins on a microcontroller. 4 of the pins must be digital pins, 1 pin must be an analog to digital conversion pin. This allows 16 sensors to operate on only 5 pins of a micro! This is a great way to connect a lot of sensors to a few pins.
You can also run the mux/demux the other direction. One serial stream connected to the SIG pin can be piped to multiple outputs.
The mux/demux also works with digital signals (like serial, I2C, SPI). This means you can hook up multiple serial devices (like a GPS TX pin, and a XBee DOUT pin) to one RX pin on a microcontroller.
The IC can control analog voltages that vary across the voltage supply range. The bidirectional switches allow any analog or digital input to be used as an output and vice-versa with a " Break-Before-Make" switching of 6ns at 4.5V. In addition, the switches have low " on" resistances and low off leakages. Includes and enable control which when high will disable all switches to their off state.
ON Resistance 70Ohms @ 4.5Vcc and 60Ohms @ 6VCC
2V to 6V operation
Wide operating temperature -55C to 125C