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Topic: LCD displays using the HD44870 , power consumption. (Read 1 time) previous topic - next topic

mauried

Many of the common 2 X 16 LCD display use this chip.
Does anyone have any ideas of how to reduce the power consumption of the display.
Most of the common displays require around 1 - 1.5 ma without a backlight yet the HD44780 controller chip specs require only 150 ua .
I dont know where the rest of the power goes.
The display Im using only changes its value around once every 1 1/2  minutes so data writes dont occur very often.
Trying to make a small battery powered Temperature sensor , and 1.5 ma
draw kills the AAA batteries.

floresta

Quote
...  yet the HD44780 controller chip specs require only 150 ua .
I dont know where the rest of the power goes.


Did you read note 10?
10. Input/output current is excluded. When input is at an intermediate level with CMOS, the excessive
current flows through the input circuit to the power supply. To avoid this from happening, the input
level must be fixed high or low.


Maybe we shouldn't be letting the four unused data leads float.


Don

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