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Subject: Re: [motm] 650 schedule..

From: "Paul Schreiber" <synth1@...>
Date: 2002-10-17

> Is there a current draw difference between the LED/LCD option? Also, any
> idea of the module current requirements?
> Would it need +/-15 as well as +5V? Does it make any sense to derive the
> +5V on board via sub regulation as opposed to a separate supply?
>

Without backlight, the LCD is nothing, like 10ma max, 4ma typical at +5V.

However, the backlight can draw 150ma at full levels. This is set by a resistor, but even at
"moderate" brightness, I'd say 70ma. Then..the 8051 uP at say 24Mhz is drawing 20ma. Call it
100ma. That's about the same as 4 average modules.

The LED design would draw about 20% MOREthan the LCD with backlight.

So, I'll use +5V supply (ie the MOTM-950) since the +-15V supply is zilch: 10ma maybe.

Paul S.