Cheap 2X16 red/black LCD tests

in testing by Ian | 5 comments

We got our hands on a few cheap 2×16 red/black LCDs of eBay for $5 a piece, these are the same LCDs from the unboxing video. In preparation to build the soldering iron driver, we tested them out with the Bus Pirate LCD adapter and the USB LCD Backpack. Initially we were worried that the red on black LCD would need a negative voltage supply, contrary to the advertisement, but it works great on a simple supply.

The USB LCD Backpack is available for $16.95 at Seeed Studio.

This entry was posted in testing and tagged , , .

Comments

  1. arhi says:

    These looks great. They use some back light to light trough that red chars or ?!

  2. arhi says:

    btw, where did you get these lcd’s? how much were they?

  3. Ian says:

    It is red LED backlight through red chars. It was around 5 bucks from seller egochina, they have a bunch but it looks like most color combos (and this one) are sold out. Here is an example (I hate ebay links because they die eventually):
    http://www.ebay.com/itm/Character-LCD-Module-Display-LCM-162-1602-HD44780-/190370286920?pt=LH_DefaultDomain_0&hash=item2c52f40d48

  4. arhi says:

    cool, thanks, very interesting.

  5. Perry Harrington says:

    My favorite way to generate a negative supply voltage is to steal the negative voltage off of a MAX233 or MAX232 chip. They can supply up to 10ma at -10v and up to 20ma. They are unregulated, so at higher current draws they put out a reduced voltage. This behavior is documented in the Maxim datasheet for the part.

Leave a Comment

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>

Notify me of followup comments via e-mail. You can also subscribe without commenting.