[SOLVED] 16 *2 LCD contrast problem

I just solved my display problem( i wasnt getting anything on display ) and now i seems to have ended with another problem.

I have set the contrast pin as specified that is connected it to 10k Pot.

but you know whats happening is, the contrast looks really good when i turn it on, but after about 10 seconds it starts fading and then it reaches a state where i can no longer see things, i have tried adjusting the POT, but i cant increase contrast anymore.
if the backlight is on, then nothing is visible.

I have also tried connecting contrast pin directly to ground, but that didnt make any changes too.

What am i missing here ?, i read in some posts that sometimes it requires Negative voltages. What am i supposed to do here to provide negative voltages ?

whats the way out ?

You're not sure if you need negative voltage? Maybe it's time to read the data sheet.

Duration of 10 seconds is fixed?
Might be due to some capacitive load. Try constantly measuring voltage at contrast pin i.e. pin 3. If voltages are changing, its fault within your circuit.
I've never used negative supply for lcd. It works well still.

Only extended temperature range LCD require a negative voltage. Check that you have 0V on the contrast pin i.e. pin 3 as stated in the previous post. Another possibility is that the power supply voltage is dropping down (are you running it from batteries?) the contrast will drop as the supply drops and will cause the display to disappear at 4.5V

exactly....ur main power supply myt be the cause of problem....just verify that....for a character lcd i dont think a negative voltage is required....which model of lcd r u using..?

Show the hardware connection.

i think problem in your board supply. i think you need to check the capacitor used for filter. no need to use negative voltage for lcd.

Yes.. the voltage was dropping to around 4.5, I added a bigger supply.. and now it seems to work well now