HD44780 - redesign

I’m about to send off for a batch of these unless this is planned for in future revs.

Basically it allows switching from 3.3v to 5v and LCD brightness is adjustable with a potmeter (0 to 5K ohms).


Are there any plans to support displays with an extended temperature range? These displays could be used for outdoor applications and require a negative voltage for the setting the LCD contrast (typically -0.1 to -2.5 volts).


Another enhancement I’d like to see is a way we can lose the ‘sleeps’ which are sometimes required when sending these displays data, or other suggestions around getting around this problem (eg faster displays). I hate pausing a CPU that has lots to do.

The only solution I know of for that is offloading the work onto a secondary MCU. I believe PIC is a common choice for these types of serial backpacks.

I wanted to keep the cost / complexity down thus no serial interface. The serial interface ones typically cost ~$20.

This thing with 5V 16x2 display will run for less than $10.

If someone were to build a display that used a secondary MCU, I’d likely pickup a couple as the difference between $10 and $20 is worth getting rid of those sleeps.

You can buy those from sparkfun. Hook up 3 wires to an extender module and you are done.

can you point me to a data sheet for those?

@ Duke Nukem - Checkout Newhaven Displays. They have serial versions in various configurations which come with Serial, SPI and I2c interfaces which are selected by a jumper.

A good introduction into the topic “LCD temperature ranges” can be found for example here: LCD Temperature Range Selection

Some example datasheets ( look inside the datasheets for “extended temperature” or “-ET”):