| ??? 04/07/06 09:55 Read: times |
#113799 - problem in contrast Responding to: ???'s previous message |
Hi,
Thank you for the solution kalpak sir.I checked the pins in the LCD.There is short between the ground and cathode. Is there any possibilties to turn OFF the backlight in the same LCD? I tried out the same connection usig another 16 pin LCD having no short between GND and cathode.Here,when the backlight is in OFF condition the characters are displayed correctly,but when i turn ON the backlight,the characters are not visible.I've adjusted the contrast to high/low position in the trimpot,but is not varying. I'm using 680R in the base of the transistor and a 1k resistor for the trimpot.Please tell me the changes to be done in the contrast circuit? Waiting for the reply, veena. |
| Topic | Author | Date |
| To turn OFF LCD backlight | 01/01/70 00:00 | |
| Not by code | 01/01/70 00:00 | |
| LCD backlight | 01/01/70 00:00 | |
| To turn OFF LCD backlight | 01/01/70 00:00 | |
| MOSFET | 01/01/70 00:00 | |
| check the connection diagram | 01/01/70 00:00 | |
| Are you confusing between contrast... | 01/01/70 00:00 | |
| Check my changes in connections | 01/01/70 00:00 | |
| In some models.. | 01/01/70 00:00 | |
| Voltage level at the backlight pins. | 01/01/70 00:00 | |
| Is cathode short to the ground pin? | 01/01/70 00:00 | |
| cathode is at 0V | 01/01/70 00:00 | |
| Did you check for short between | 01/01/70 00:00 | |
| problem in contrast | 01/01/70 00:00 | |
| See earlier PNP solution | 01/01/70 00:00 | |
| Thank you very much | 01/01/70 00:00 | |
using 5V for backlight? | 01/01/70 00:00 |