| ??? 09/29/08 21:57 Read: times |
#158660 - Point taken Responding to: ???'s previous message |
Andy Neil said:
David Prentice said:
AFIK, all ARMs run on 3.3V and will not tolerate 5V on every pin. From the documentation, the GPIO ports are 5V tolerant but if you select an alternate function you cannot assume the tolerance. That sounds like waaaaaay too much of a sweeping generalisation! ARM is an architecture, not a chip - so it's up to the individual implementation what supply voltage it runs on, what GPIOs it may or may not have, whether they may or may not have alternate functions, whether any, some, or all may or may not be 5V tolerant, etc, etc... Point taken. I expressed myself badly. I am not aware of any ARM chips that will run on a Vcc higher than 3.3V Some ARM chips have 5V tolerant GPIO pins. The only ARM that I have used is the Philips LPC2103, which has 5V tolerance on the GPIO but is a little unclear about the tolerance of a pin if used as special function. Depending on your external peripheral chips or circuitry, it can be inconvenient to level-shift. David. |
| Topic | Author | Date |
| When to ARM ? | 01/01/70 00:00 | |
| to ARM or not to ARM | 01/01/70 00:00 | |
| Comments | 01/01/70 00:00 | |
| Point taken | 01/01/70 00:00 | |
| Most often pin config doesn't matter | 01/01/70 00:00 | |
| Cortex-M3 | 01/01/70 00:00 | |
| ARMs | 01/01/70 00:00 | |
| 3V vs 5V | 01/01/70 00:00 | |
| Excellent | 01/01/70 00:00 | |
| NXP LPC2000 | 01/01/70 00:00 | |
people migrating from PICs. | 01/01/70 00:00 |