LCD tips pls

[japl]

Hello,

Ive seen an LCD (hitachi 44780) tester that has an LED indicator when the LCD is working properly it lites up and when the LCD doesnt work it doesnt lite up so Im wonderin where in the LCD circuit, assuming im using a 2 wire to PIC microcontroller configuration (myke predko's style), would i put the LEDs on so that based on the LEDs lite i can say that the LCD is workin fine.

I've manage to break an LCD before :shock: , Ive used a 15V supply w/ LM7805 regulator can someone plz give me more helpful tips on how to prevent more unnecessary voltage entering( im broke my LCD this way) the LCD unit so as not to break it again :lol:

 

[panic mode]

was the LCD connected to 15 or 5V? I've used several and they
worked fine with batteries (4.5, 4,8 or even 6V) and PSU (5V).
how did you connect 7805?

 

[japl]

Hi panic mode

It was connected to the 5V output of the LM7805. I used the LM directly the LM's output directly connected to the LCD VCC's and GND.

 

[panic mode]

that should be perfect if wired correctly. i've found nice LCD characgter display with background lighting. never bothered to look for datasheet, just connected the bkg lighting to 5V as well. it didn't burn but it did get hot and after while LCD started changing colors (running for ca 10minutes and powerd by old-PC power supply). after it cooled off, everything was fine. i guess using series resistor for it would be right thing to do.