[sdiy] current sink idea

[Tom Wiltshire]

I think he meant instead of the DAC, not to drive the backlight directly. I agree that would be asking for trouble. 

Roman mentioned using a PWM pin as a basic DAC followed with a simple RC and the current sink, and that should be fine.

> On 30 Nov 2024, at 11:53, Mike Bryant <mbryant at futurehorizons.com> wrote:
> 
> One problem is low cost displays aren't shielded so you'll transmit the PWM frequency everywhere
> 
> From: Synth-diy <synth-diy-bounces at synth-diy.org> on behalf of Gordonjcp <gordonjcp at gjcp.net>
> Sent: 30 November 2024 11:48
> To: synth-diy at synth-diy.org <synth-diy at synth-diy.org>
> Subject: Re: [sdiy] current sink idea
>  
> On Sat, Nov 30, 2024 at 09:17:13AM +0100, Roman Sowa via Synth-diy wrote:
> > with 2 days ago.
> > Special needs require special solutions - I needed to control display's
> > backlit intensity from internal DAC of the microcontroller, which
> 
> Immediate first question - why not use a PWM pin?
> 
> --
> Gordonjcp
> 
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org
> View archive at: https://synth-diy.org/pipermail/synth-diy/ <https://synth-diy.org/pipermail/synth-diy/>
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy <https://synth-diy.org/mailman/listinfo/synth-diy>
> Selling or trading? Use marketplace at synth-diy.org
> 
> From: Synth-diy <synth-diy-bounces at synth-diy.org <mailto:synth-diy-bounces at synth-diy.org>> on behalf of Gordonjcp <gordonjcp at gjcp.net <mailto:gordonjcp at gjcp.net>>
> Sent: 30 November 2024 11:48
> To: synth-diy at synth-diy.org <mailto:synth-diy at synth-diy.org> <synth-diy at synth-diy.org <mailto:synth-diy at synth-diy.org>>
> Subject: Re: [sdiy] current sink idea
>  
> On Sat, Nov 30, 2024 at 09:17:13AM +0100, Roman Sowa via Synth-diy wrote:
> > with 2 days ago.
> > Special needs require special solutions - I needed to control display's
> > backlit intensity from internal DAC of the microcontroller, which
> 
> Immediate first question - why not use a PWM pin?
> 
> --
> Gordonjcp
> 
> ________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org <mailto:Synth-diy at synth-diy.org>
> View archive at: https://synth-diy.org/pipermail/synth-diy/ <https://synth-diy.org/pipermail/synth-diy/>
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy <https://synth-diy.org/mailman/listinfo/synth-diy>
> Selling or trading? Use marketplace at synth-diy.org <mailto:marketplace at synth-diy.org>________________________________________________________
> This is the Synth-diy mailing list
> Submit email to: Synth-diy at synth-diy.org <mailto:Synth-diy at synth-diy.org>
> View archive at: https://synth-diy.org/pipermail/synth-diy/ <https://synth-diy.org/pipermail/synth-diy/>
> Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy <https://synth-diy.org/mailman/listinfo/synth-diy>
> Selling or trading? Use marketplace at synth-diy.org <mailto:marketplace at synth-diy.org>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20241130/b530df3f/attachment.htm>