Datasheet

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EA DOG-M
EA DOG SERIES
With its EA DOG series, ELECTRONIC ASSEMBLY presents the world’s first display series which
will run on 3.3 V systems without auxiliary power. They can, of course be used on traditional 5 V
systems.
Unlike normal LCD modules, you order the display and the corresponding backlight separately. This
gives you a wealth of possible combinations.
Designed for compact hand-held devices, this modern LCD range provides a number of real benefits
with or without backlight:
* extremely compact at 55 x 31 mm at the standard font size of 5.57 mm (2 x 16)
* ultra-flat at 2.0 mm without backlight or 5.8 mm including LED backlight
* 4-bit, 8-bit and SPI interface (4-wire)
* typical power consumption of only 250µA in full operation (LED white backlight as of 3mA)
* easy installation by simply soldering into the board
* A whole range of design variants (63) can be supplied as of single units
* Changing background color
SETTING THE CONTRAST
The contrast on all displays of the EA DOG series can be set with a command. This is done using
bits C0 through C5 in the commands "Contrast Set" and "Power/Icon Control/Contrast Set". Generally,
the contrast is set once and kept constant across the entire operating temperature range (-20 through
+70°C) thanks to the integrated temperature compensation function.
Even when run at 3.3 V, the displays do
not require any additional negative voltage!
LED BACKLIGHTS
6 different variants are available for individual backlighting:
white, yellow/green, blue, red, amber and full color.
For monochrome backlights, 2 separate LED paths are
available, which can be switched in parallel or in series to
ideally match the system voltage. This means that all the
backlights can be run either at 5 V or at 3.3 V.
Operation of the backlight requires an external series
resistor for current limiting. This can be calculated from
R=U/I; you will find the values in the table. To improve life
time it is recommanded to use a current source only.
The operating life of the yellow/green, red and amber
backlights is 100,000 hours and that of the white and blue
backlights much shorter.
Important: Never operate the backlight directly on a 5 V/
3.3V supply, as this can immediately destroy the LEDs!
INSTALLATION
First, the display and the corresponding backlight are
clipped together. The complete unit is then inserted into a
PCB and soldered. Note that the 4 pins for the backlight
must also be soldered from the top.
Important: There are one or two protective films on the
display (top and/or rear side) and one on each backlight.
Those have to be removed during or after production.
yellow/green
EA LED55x31-G
Forwar
voltage
Current
max.
Limiting resistor
@ 3,3 V @ 5 V
Connected in parallel 2,2 V 80 mA 14 ohm 35 ohm
Connected in series 4,4 V 40 mA - 15 ohm
white
EA LED55x31-W
Forwar
voltage
Current
max.
Limiting resistor
@ 3,3 V @ 5 V
Connected in parallel 3,2 V 60 mA 1,6 ohm 30 ohm
Connected in series 6,4 V 30 mA - -
blue
EA LED55x31-B
Forwar
voltage
Current
max.
Limiting resistor
@ 3,3 V @ 5 V
Connected in parallel 3,2 V 60 mA 1,6 ohm 30 ohm
Connected in series 6,4 V 30 mA - -
amber
EA LED55x31-A
Forwar
voltage
Current
max.
Limiting resistor
@ 3,3 V @ 5 V
Connected in parallel 2,4 V 80 mA 11 ohm 32 ohm
Connected in series 4,8 V 40 mA - 5 ohm
red
EA LED55x31-R
Forwar
voltage
Current
max.
Limiting resistor
@ 3,3 V @ 5 V
Connected in parallel 2,1 V 80 mA 15 ohm 36 ohm
Connected in series 4,2 V 40 mA - 20 ohm
Full color
EA LED55x31-RGB
Forwar
voltage
Current
max.
Limiting resistor
@3,3 V @ 5 V
Connected in parallel 4 V 125 mA - 3x24 ohm