| ??? 01/24/08 14:18 Read: times |
#149923 - Well, I have yet to see any VCC that ... Responding to: ???'s previous message |
... is stable (ratiometric = stability, not precision, needed) within anything better than, say, 2%. A 2% potential difference between the reference read and the input read is not even good enough for an 8 bit ADC. Even a 2 0/00 variation (10mV) will make 2 bits of error in a 10 bit DAC.
Put a scope (an AC mode at 100mV input) on the Vcc for any uC circuit and see. Erik |
| Topic | Author | Date |
| Atmel T89C51CC02: ADC reference voltage | 01/01/70 00:00 | |
| No, unless you mean VAVCC | 01/01/70 00:00 | |
| VAVCC usable as ADC reference voltage? | 01/01/70 00:00 | |
| Datasheet says that you can | 01/01/70 00:00 | |
| 'can" "should' and 'good' are 3 different words | 01/01/70 00:00 | |
| varef is specified 2,4...3V range | 01/01/70 00:00 | |
| but not if you want any precision | 01/01/70 00:00 | |
| why not | 01/01/70 00:00 | |
| Well, I have yet to see any VCC that ... | 01/01/70 00:00 | |
| Does that mean... | 01/01/70 00:00 | |
no,yes | 01/01/70 00:00 |