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Subject: Re: Power Supply Sequencing

From: "djbrow54" <davebr@...>
Date: 2006-03-16

The backlight is on a separate connector. I think we can run the
backlight at very low current. I am running a 20x2 backlight at 18
mA, far from the spec of 130+ mA.

As far as voltage feedback and the DAC, the LCD only connect to Tx and
Reset and both are inputs. I don't see any way for it to feedback +5
volts.

My personal feeling is that we can make the LCD board low enough
current that you could feed it off of a 7805 regulator on the main
PCB. The AVR is ~5 mA and the LCD logic is 3 mA. If we can run the
backlight at <20 mA then the entire LCD board is 28 mA.

Dave

--- In ComputerVoltageSources@yahoogroups.com, "Grant Richter"
<grichter@...> wrote:
> For an LCD display board. I sure hope the 200 ma backlight connector
> is on a seperate pad from the main 5 volt so the wires can be run
> seperately. A display module probably doesn't need 15 volts at all.