# Multiplexing analog signal

Joined Feb 22, 2007
53
I'm using a Picaxe PIC for a project and I want to have 4 analog signals connected to the same input (before you ask it's just my way of learning new stuff) I'm an expert in digital circuits so my idea is to create a analog multiplexer (4:1). Is this possible? If yes: how?

Thx...

#### nomurphy

Joined Aug 8, 2005
567
For wider voltage ranges, try the DG409 or older ADG509.

For an 8:1, I believe its the DG508.

#### Ron H

Joined Apr 14, 2005
7,012
For wider voltage ranges, try the DG409 or older ADG509.
I suggested the 74HC parts because he said he was interfacing with a PIC. It's true that they can only handle about 0-5V.

Joined Feb 22, 2007
53
Thank for your answers... I'll use the 74HC farts for its easy interfacing and because the 0 to 5V limit is not a worry.

#### nomurphy

Joined Aug 8, 2005
567
Just to be clear, the switching/addressing logic is all relative to +5V.

But if your switched I/O signals are greater than +/-5Vpk, then you can't/shouldn't use the HC/HCT parts.

#### Papabravo

Joined Feb 24, 2006
12,301
The old CD4066 has 4 individual switches which can be configured as a 4:1 mux and lots of other things as well.

Joined Feb 22, 2007
53
The purpose of the signals will be to carry sensors data (temperature, light, ...). When I design the sensors I'll make their output between 0 and 5V. Is this possible? My doubt comes from the Vee voltage can someone explain it to me?

EDIT: and what Vcc has to do with Vee?

#### Ron H

Joined Apr 14, 2005
7,012
The purpose of the signals will be to carry sensors data (temperature, light, ...). When I design the sensors I'll make their output between 0 and 5V. Is this possible? My doubt comes from the Vee voltage can someone explain it to me?

EDIT: and what Vcc has to do with Vee?
It's possible. If you need help, you'll need to post what kind of sensors you have, with datasheets if possible.

EDIT: You should be able to do it without a negative supply.