| ??? 02/01/06 10:46 Read: times |
#108865 - 3V micro core LCD Solution Responding to: ???'s previous message |
I have 3 experiences.
1. P89LPC932 Philips 3v 80c51 variant With 5V LCD Program LPC932 micro I/O to open drain and use 10k pull-ups to 5v, on each of the LCD input signal lines. LPC932 is 5V I/O tolerant 5V needed some where. 2. 3V micro without 5V I/O tolerant pins with 5V LCD Some 5V CMOS LCD IC's have 5V TTL logic levels thresholds (EG like 74HCT).... So you can drive the logic of the LCD controller directly....BUT the LCD Glass is designed for 5V (Vlcd signal). So a charge pump or steal 5v~10v from a MAX232 supply cap has worked for me in the past.... as Vlcd . 3. 3V lcd Some have the charge pump on the LCD PCB...3v ~ 5v conversion on the LCD. Some LCDs are truly 3V complete. JG |
| Topic | Author | Date |
| 3 Volt LCD Module. | 01/01/70 00:00 | |
| pull-ups | 01/01/70 00:00 | |
| May be not required | 01/01/70 00:00 | |
| Are you asking for interface level? | 01/01/70 00:00 | |
| Power Supply Is 3 Volt. | 01/01/70 00:00 | |
| 5V generation from 3V | 01/01/70 00:00 | |
| 3V micro core LCD Solution | 01/01/70 00:00 | |
| I'll answer when the therad is moved | 01/01/70 00:00 | |
| Thanks Ijaz Ahmed. | 01/01/70 00:00 | |
| A different approach | 01/01/70 00:00 | |
Thanks Grant Beattie. | 01/01/70 00:00 |