4051 Analog Multiplexer Concept Question

Hello all,

I am going to use the 4051 multiplexer in one of my projects and I am wondering about the analog out pin. Since the select pins range from 000 to 111, will this mean that if my 4051 is being supplied by 5V, 000 will correspond to 0 Volts, 001 to .658 Volt, 010 to 1.25V etc etc until 111 would give 5V out? Or will this just pass through the voltage of the selected channel?

Probably a dumb question but its pretty important to know.

Thanks

Palbert said:

Hello all,

I am going to use the 4051 multiplexer in one of my projects and I am wondering about the analog out pin. Since the select pins range from 000 to 111, will this mean that if my 4051 is being supplied by 5V, 000 will correspond to 0 Volts, 001 to .658 Volt, 010 to 1.25V etc etc until 111 would give 5V out?

Click to expand...

This functionality is that of a Digital-to-Analog Converter (DAC).

Palbert said:

Hello all,

Or will this just pass through the voltage of the selected channel?

Click to expand...

This is the functionality of a multiplexer. This is what you will get. In reviewing the UTC datasheet for the 4051, page 5 has a nice little truth table to clear everything up for you.

Ahh, yeah that would make sense. Welp, onto the DAC it is for me...

Thanks ADWSystems.

A CD4051 is a multiple switch. It has either 1 input and one of 8 outputs or it has one of 8 inputs and 1 output.
It has a supply voltage from 3V to 18V. It has 3 binary inputs to select which switch is turned on. It has an Inhibit pin.
A switch that is turned on is like a 120 ohm resistor from input to output.

Thanks for the response audioguru and sorry for the late response. I just ended up writing a program for my micro which just polls pins. Thanks for the help though.