Hello, I want to apologize at first for the ugly schematic, I am a newbie at all of this.
I'm trying to wire up my dg413. I want to switch between a variable voltage from 0-5v and a fixed voltage. I can't get this to work, always shows weird numbers when measuring.

Regards

 

I believe you need to connect the VL pin to ground in order to accomodate input voltages down to zero volts.
If that doesn't work try increasing the supply voltage to 15 volts or connecting a 10K resistor from the common connection of IN3 and IN4 to ground

 

Hello, I want to apologize at first for the ugly schematic, I am a newbie at all of this.
I'm trying to wire up my dg413. I want to switch between a variable voltage from 0-5v and a fixed voltage. I can't get this to work, always shows weird numbers when measuring.

Regards

View attachment 236168

The way you have it wired is with a normally closed switch connected to a normally open one. When you flip the control input you just reverse the two, maintaining the status quo, so no signal gets through from the pot!

 

apologize at first for the ugly schematic,

First rule is don't run wires through a component.
It makes the schematic hard to read.

 

First rule is don't run wires through a component.
It makes the schematic hard to read.

I made a mistake reading the schematic in reply #3, my excuse being my old eyesight and the schematic as drawn.
Looking at it again, and reading the datasheet, I think the problem may be that the VL is set for a TTL input level, but V+ at 12V means it expects a CMOS high level, so isn't switching. So connecting V+ to 5V should cure the problem.

 

And another thing, when drawing circuit schematics, don't use the IC pin layout.
Use a functional symbolic diagram so that it is easier to follow the function of the IC.

Here is what a functional diagram looks like:


Make sure to include the IC pin numbers in the drawing.

 

I believe you need to connect the VL pin to ground in order to accomodate input voltages down to zero volts.
If that doesn't work try increasing the supply voltage to 15 volts or connecting a 10K resistor from the common connection of IN3 and IN4 to ground

Putting a pulldown resistor to the input for the control logic seems to have solved the problem.