Description
DESCRIPTION:
*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).
*It works with both digital and analog signals (the voltage can’t be higher than VCC),and the connections function in either direction.
*To control it, connect 4 digital outputs to the chip’s address select pins (S0-S3),and send it the binary address of the channel you want (see the datasheet for details).
*This allows you to connect up to 16 sensors to your system using only 5 pins!
*Since the mux/demux also works with digital signals,you can use it to pipe TTL-level serial data to or from multiple devices.
*For example, you could use it to connect the TX pins of 16 devices to one RX pin on your microcontroller.
*You can then select any one of those 16 devices to listen to.
*If you want two-way communications, you can add a second board to route your microcontroller’s TX line to 16 device’s RX lines.
*By using multiple boards, you can create similar arrangements for I2C, SPI, etc.
*The internal switches are bidirectional, support voltages between ground and VCC,have low “on” resistance and low “off” leakage, and to prevent crosstalk, perform “break- before-make” switching.
*The board also breaks out the chip’s “enable” pin, which when driven high,will completely disconnect the common pin (all switches “off”).
