piclist 2001\04\18\173055a >
Thread: Charge pump for LCD Vlc ?
face BY : David VanHorn email (remove spam text)

At 10:38 PM 4/18/01 +0300, Peter L. Peres wrote:
> >I have used the PIC's crystal out pin before for this, no problem. I was
> >able to use an "extended temperature" type LCD this way.
>Uhh. Okay, you win the prize for simplicity ;-).
>However, do you need a broadcast license for this ?

Highly likely!  You're better off, if you must, to do a charge pump off one
of the I/O pins.

>This drove a standard inductor to obtain higher voltage.
>This was using 455kHz ceramic resonators on the PIC. It was noisy enough
>to make me think twice before using it again.

455k is getting a little adventurous, but I would only expect layout-driven
Gonna be a lot of RF current into that gate cap, and the source needs a
solid link back to the uP gnd and VCC pins.
I'm wondering if you were turning the fet fully on and off, since the
output drive on the pic is relatively wimpy for such things.

Dave's Engineering Page: http://www.dvanhorn.org
Where's dave? http://www.findu.com/cgi-bin/find.cgi?kc6ete-9

http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


In reply to: <Pine.LNX.4.10.10104182234370.678-100000@plp.plp.home.org>
See also: www.piclist.com/techref/io/lcd/pic.htm?key=lcd
Reply You must be a member of the piclist mailing list (not only a www.piclist.com member) to post to the piclist. This form requires JavaScript and a browser/email client that can handle form mailto: posts.
Subject (change) Charge pump for LCD Vlc ?

month overview.

new search...