Need help verifying "dead" CFAG320240CX-TFH-T-TS LCD


New member
Is there an "at home" test procedure I can use to test whether or not this LCD is "dead?" (i.e. pin-to-pin ohm check, test voltage (by the way, it generates Vee and Vo fine), etc.) The backlight works and I have had graphics and text displayed successfully on the screen before, but now, after transitioning from breadboard to PCB, I get nothing (until I adjust the potentiometer on the back of the LCD and then I have thick vertical bars of "junk"). I've been troubleshooting it for days, and finally had to remove it from my system in order to test my microcontroller (a PIC24F...) by itself. I wrote a flashing program that flashed every digital output on my PIC and I checked each with an LED and they all worked properly. In my interface to the LCD (6800 mode) I only write, and I manually control it with digital outputs. I have completely resoldered my connections and still nothing, but everything ohms out fine, so I'm assuming my LCD is the culprit.

Anyway, I need to find out if this LCD is dead or not quickly, so, if need be, I can order a new one to replace it in time to GRADUATE! :eek:


James Washington
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