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How to light backlight and change the contrast in this LCD ?

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gold_kiss

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LCD question

Recently i purchased a 16x2 LCD. Can any one give me some information as to how do i light the backlight?

it has basically 16 pins.
Pin 1 VSS
Pin2 VCC
Pin3 VEE
Pin4 RS
Pin5 R/W
Pin6 E
Pin7 DB0
Pin8 DB1
Pin9 DB2
Pin10 DB3
Pin11 DB4
Pin12 DB5
Pin13 DB6
Pin14 DB7
Pin15 LED+
Pin16 LED-


Also can anyone tell me how do i change the contrast of the seqment of the LCD?
Any kind of schematic and explanation would be of great help.
Thanks,
Gold_kiss
 

Re: LCD question

The backlight should be pins 15 and 16 but be careful some displays do not have current limiting resistors built in. You can connect +5v but use a series resistor of 47 ohms first.

The contrast can be regulated by connecting a pot (which has +5v and ground connected) to pin 3 most displays only show the characters when the applied voltage is around 0 V.

best regards
 

Re: LCD question

LED+ and LED- pins goes to led.But some lcd munufacters put resistance on module.
Attach 10 ohm resister to LED+ pin and attach this pin to variable power supply posite output.And attach LED- pin to power supply other negative pin.Start voltage from 0v to higher voltage slowly .But you dont forget current measurment for this leds.
LCD pin 3 for contrast adjustment.Attach this pin to 10kohm variable resistor middle point and variable resisters other one pin attach pin 1(vss=0v) and other pin to vdd(pin2).
 

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