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LCD Plug (v1)


The LCD Plug is a small board which is designed to sit piggy-back on an HD44780-compatible LCD display with 16-pin connector - the plug is based on the same MCP23008 as the Expander Plug:


DSC_0722.JPG DSC_0721.JPG


The backlight can be controlled via software to reduce power consumption. A BC817 is now used as switch, it can drive up to 500 mA for the backlight. The driver software and an "lcd_demo" example sketch is included in the Ports library.


An I2C bus running at 3.3V is used for I/O, with all the power and signal lines brought out to to both sides of the board to allow daisy-chaining with other I2C-conformant boards.


For additional details, see http://news.jeelabs.org/2009/11/01/lcd-plug/



CONFIGURATION

    The I/O expander chip on this plug is set to respond to I2C address 0x24.

    The logic supply voltage has to be jumpered to either the PWR or the +3V pin.

    The backlight voltage has to also independently be set to either PWR or +3V.

    There is room for a backlight current limiting resistor, or use a jumper to bypass it.

    And lastly, there is a mini trimpot on the board to adjust the LCD contrast level.



HEADER PINOUTS

    _00000319.pdf

    


DESIGN INFO

    Dimensions: 21.1 x 41.9 mm

    CadSoft EAGLE design files:

        http://jeefiles.equi4.com/jlpcb-043.sch

        http://jeefiles.equi4.com/jlpcb-043.brd

    Schematic as PDF: http://jeefiles.equi4.com/jlpcb-043.pdf

    This plug can be operated at 5V as well as 3.3V.


This board uses the conventions of a JeePlug and can be used with the ports on a JeeNode. It can also be used with other boards and MCU's, if you hook it up properly and adapt the interface code for it.



WHERE TO GET IT

    http://shop.jeelabs.com/products/lcd-plug



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