Arduino Forum

Using Arduino => General Electronics => Topic started by: Joes on Sep 14, 2012, 10:36 pm

Title: smooth 0-10v output
Post by: Joes on Sep 14, 2012, 10:36 pm
hi there im trying to convert my 0-5v pwm output of the arduino to a smooth 0-10v for a high frequency flourescent i come across this just wanted to make sure that this would work or if people have got better suggestions?

http://aartsite.nl/licht/o_5vhrfi.htm  (http://aartsite.nl/licht/o_5vhrfi.htm)
Title: Re: smooth 0-10v output
Post by: retrolefty on Sep 14, 2012, 10:49 pm
That circuit looks like a good and proper way to accomplish the task.

Lefty
Title: Re: smooth 0-10v output
Post by: Joes on Sep 14, 2012, 11:01 pm
thanks  XD
Title: Re: smooth 0-10v output
Post by: Joes on Sep 15, 2012, 11:49 am
on that he is using a LM324 i dont need 4 lost of it, just 2 so will this be fine?
http://uk.rs-online.com/web/p/operational-amplifiers/0463145/  (http://uk.rs-online.com/web/p/operational-amplifiers/0463145/)
Title: Re: smooth 0-10v output
Post by: Docedison on Sep 15, 2012, 01:30 pm
Yeah, I do it's probably what was used originally, the 358 is a Very common Op-Amp. Made by almost everyone in the semiconductor business and there are several dozen others with the same pin-out with varying characteristics. Since the device is driving a transistor it is a current feedback loop. It is easy to misuse and if misused not perform with anything like expected. there is a hard limit of about 200 mA on that transistor and a power type will not perform either as with most op-amps the output drive current is limited so controlling a bigger transistor has it's issues. Good Luck.

Doc
Title: Re: smooth 0-10v output
Post by: MarkT on Sep 15, 2012, 01:50 pm
The only problem with that circuit might be stability - adding a 47pF capacitor between the opamp output and its inverting (-) input would cure that.

The issue is that the opamp feedback path has to go through a potentially slow component (transistor) and drive a capacitive load (C3) - this might introduce enough phase-lag to induce oscillations.  The small capacitor would provide a high-frequency lagless feedback path to quell such a tendancy without affecting low frequency behaviour.
Title: Re: smooth 0-10v output
Post by: akis31 on Nov 16, 2014, 10:31 pm
i am doing the same project, i want to control a dimmable ballast,
is this circuit working? could you share the schematic please?
Title: Re: smooth 0-10v output
Post by: raschemmel on Nov 16, 2014, 11:31 pm
Are you planning to use an RC LP filter between the arduino and the op amp non-inverting amplifier
circuit ?
Title: Re: smooth 0-10v output
Post by: akis31 on Nov 17, 2014, 01:06 am
i have already an Lm 358n and an Lm 741, i am thinking of using two 10k res as Rf and Rin connected to the invrerting input and a 22k res and 0,47u cap at the non-inverting input.
But reading older posts they say that using a simple npn transistor can do the same job.
Title: Re: smooth 0-10v output
Post by: akis31 on Nov 17, 2014, 10:36 pm
any other idea or suggestion?