Amplifying DAC output for lab PSU

[tbj]

Hi all.

I've been following Dave's Lab PSU series of videos and I'm a bit stuck on the one where he shows how to convert the PSU to PWM control.

I'm not sure if this was mentioned in the video or not (I couldn't find it), but let's say I have an output of 0-5v from my DAC. Now let's say my PSU needs to go 0-15v.

What's the best way to linearly amplify the DAC output with a gain of 3?

My current thinking is to use a non-inverting op amp in single supply configuration like so (simulated, works OK, no idea if this would work with real op-amps).



But even with a rail-to-rail opamp, it won't be able to go all the way down to 0 volts, will it?

Is there a better way?

[bson]

Your DAC output likely won't be rail-to-rail either.
Wire it up and see what happens!

Edit: if the low end of the DAC gets too close to ground you'll need the bias the op amp input.  This can be as simple as a pair of resistors.  But measure it first.