Dave has proposed testing the actual LCD as his experience is that much less
current is required for the backlight than specified. A 78L05 is specified
to handle 100 mA. I'd recommend derating of 60%, for 60 mA. Backlight
specification was 160 mA, Dave has run a similar one at 16 mA with good
results.
I'm ordering one myself tonight.
Regardless, there's tons of room on the LCD Support PCB, 30 x 85 mm,
assuming it mounts parallel to the LCD assembly using standoffs. We could
fit a T-220 7805 or LM341 if needed.
John Loffink
The Microtonal Synthesis Web Site
http://www.microtonal-synthesis.comThe Wavemakers Synthesizer Web Site
http://www.wavemakers-synth.com > -----Original Message-----
> From: ComputerVoltageSources@yahoogroups.com
> [mailto:ComputerVoltageSources@yahoogroups.com] On Behalf Of harrybissell
> Sent: Tuesday, March 14, 2006 10:46 PM
>
> I suggest a big wish list, then pare down to the amount that
> will fit on the PCB size you want without making the
> density too high.
>
> Really high density will amke the layout hard, possibly
> affect yeild and the ability of some folks to successfully
> complete the project.
>
> I'm all for incorporating a good feature set, but its for sure
> that 'creeping featurism' will set in if we're not careful.
>
> The 78L05 is very unlikely to support the requirements of the LCD
> backlight.
>
> I'm agreeing if you just want the 5V for the LCD itself... the 78L05
> will handle that.
>
> (maybe I'm not up to speed yet, there are only a couple hundred posts
> not counting files etc... :^)
>