My current project requires reading five capacitive moisture sensors (3-wire). I am using an ATMega 2560 R3 compatible board. Instead of using five analog input pins I would like to use a mux board to one analog input (mostly for coding reasons). Do you have a product I can use? The ideal product would be like the I2C board with the eight jtc ph connectors. Could I perhaps use that mux?
Thank You,
Steve Leach
Hi Steve.
I think you’re looking at the [Qwiic Mux, and that’s digital only so it won’t work with an analog signal.
The [CD74HC4067 or [74HC4051 would work with an analog signal though.](SparkFun Multiplexer Breakout - 8 Channel (74HC4051) - BOB-13906 - SparkFun Electronics)](SparkFun Analog/Digital MUX Breakout - CD74HC4067 - BOB-09056 - SparkFun Electronics)](SparkFun Qwiic Mux Breakout - 8 Channel (TCA9548A) - BOB-16784 - SparkFun Electronics)
Thanks Chris. You are correct that I was thinking about the QWIIC Mux. I would like to use the QWIIC type connectors so I will research making a pcb that will accommodate the connectors and the 74HC4051 breakout board (hopefully those will be back in stock soon). I appreciate your help.
Steve
I found with 74HC4051 with a 5VDC on VCC when I SEL a Y with a 5.5VDC signal Z will change to this, but trying to SEL any other Y after that, Z stays at 5.5VDC. If all the Ys are < VCC I am able to change between them all without any latching.
I could fix this by going to 10VDC on VCC, however, one of my Ys will be a 0-10VDC signal so I am worried about it latching. It says 10VDC is MAX for VCC. I am wondering if I should try 11-12VDC on VCC to prevent latching. Will it not latch to 10VDC Y with VCC at 10VDC? Or am I doing something else wrong?