General > Buy/Sell/Wanted

Sharp Memory LCD breakout for sale

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reagle:
I have a few boards from my prototype build for sale.

http://kuzyatech.com/first-product-for-sale-sharp-memory-lcd-breakout

cookie:
I've been searching this data for a while

reagle:
One left! If anybody has suggestions/feature requests etc- now may be a good time.

One thing I am considering adding  is a very low Iq boost supply so the 5V LCD version can run off 3.3V supply. (The 3.3V versions appears to be much harder to come by, and the GPIO will handle both 3.3 and 5V as is).  Oddly enough, all the boost converters suggested by Sharp draw more quiescent current than the display they would be powering. Feels kinda ridiculous to feed 4uA to the display but 5-10mA to the regulator.

mikeselectricstuff:

--- Quote from: reagle on September 02, 2012, 04:04:35 am ---One left! If anybody has suggestions/feature requests etc- now may be a good time.

One thing I am considering adding  is a very low Iq boost supply so the 5V LCD version can run off 3.3V supply. (The 3.3V versions appears to be much harder to come by, and the GPIO will handle both 3.3 and 5V as is).  Oddly enough, all the boost converters suggested by Sharp draw more quiescent current than the display they would be powering. Feels kinda ridiculous to feed 4uA to the display but 5-10mA to the regulator.

--- End quote ---
I've found that the 400x240 one runs OK at 3.3v (just - fades at 3.2v).
If you have 3.3v chances are you're deriving it from a higher supply somewhere that may be suitable without further boosting - e.g. a single li-poly cell.
Look at charge pumps for low IQ boost converters - you can probably do it with a toggling IO pin (maybe the COM signal) and a couple of diodes and caps.
 

baljemmett:

--- Quote from: reagle on September 02, 2012, 04:04:35 am ---One thing I am considering adding  is a very low Iq boost supply so the 5V LCD version can run off 3.3V supply. (The 3.3V versions appears to be much harder to come by, and the GPIO will handle both 3.3 and 5V as is).  Oddly enough, all the boost converters suggested by Sharp draw more quiescent current than the display they would be powering. Feels kinda ridiculous to feed 4uA to the display but 5-10mA to the regulator.

--- End quote ---

Perhaps something like the REG710-5, which has a quiescent draw of < 0.1mA (65uA typical), which isn't necessarily great but is a couple of orders of magnitude better at least.  It's a charge pump, as Mike suggests, and there are probably far better but it's one that impressed me when I used it in a low-power prototype before.

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