From: Josh Koffman <joshybear@gmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Sat, 29 Aug 2020 13:42:55 -0700
Subject: [EE] High Side LCD Backlight Control
Thread-Topic: [EE] High Side LCD Backlight Control
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Repost with topic tag - I am so ashamed...

Hi all,

I'm working on a small project that uses a graphic LCD. I'd like to be
able to control the backlight (possibly PWM for brightness). On this
module the backlight ground is tied to the module ground, so I can't
switch the low side.

The backlight runs at 3.3V and maxes out at about 50mA. A bit of extra
capacity might be nice just in case I ever size up a bit on the
screen.

What would be a good way to handle this? Space will be a bit limited
so fewer parts would be better, and this is a low volume thing so I'm
happy to spend a bit more on a transistor if it means fewer external
parts. 3.3V is definitely not my area of expertise when it comes to
switching, so any help would be appreciated.

Thank you!

Josh
--=20
A common mistake that people make when trying to design something
completely foolproof is to underestimate the ingenuity of complete
fools.
        -Douglas Adams
--=20
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