| Kai Klaas 06/22/09 07:26 Modified: 06/22/09 07:31 Read: 160 times Germany |
#166342 - MAX1232 + 4k7 pull-up Responding to: Aleksandar Stancic's previous message |
Aleksandar said:
Does anyone have experience with ED2 regarding brown-outs, etc? Should I implement a reset IC or is internal circuit sufficient? I would use a MAX1232 in combination with 4k7 pull-up at its reset pin. I would also spend an additional 10k pull-up at PSEN pin of micro. The internal weak active pull-up presents a rather high impedance to noise and glitches, which is the reason I use 10k pull-ups at most of the port lines. A good 10µF cap (X5S, 0805, e.g.) across the Vcc line near micro and MAX1232 and the use of a solid ground plane is a must! Kai |
| Topic | Author | Date |
| AT89C51ED2 changing speed on its own | Aleksandar Stancic | 06/21/09 03:21 |
| apply proper reset | Jan Waclawek | 06/21/09 05:37 |
| apply proper reset | Aleksandar Stancic | 06/21/09 12:21 |
| then that's R0 not R1 | Jan Waclawek | 06/21/09 14:57 |
| MAX1232 + 4k7 pull-up | Kai Klaas | 06/22/09 07:26 |
| I beliebe this chip has a built-in watchdog and thus ... | Erik Malund | 06/22/09 09:43 |
| I don't like those on-chip watchdogs and Vcc monitors | Kai Klaas | 06/22/09 10:35 |
| Should be always on | Per Westermark | 06/22/09 10:47 |
| external vs internal | Erik Malund | 06/22/09 13:18 |
| .. | Aleksandar Stancic | 06/22/09 13:45 |
| Ground plane? | Kai Klaas | 06/22/09 14:01 |
| no ground plane | Aleksandar Stancic | 06/22/09 14:10 |
| choose a "magic" frequency crystal ... | Jan Waclawek | 06/22/09 15:00 |
20MHz and 57600 | Aleksandar Stancic | 06/22/09 17:33 |