| ??? 06/22/09 15:35 Modified: 06/22/09 15:37 Read: times |
#166349 - I don't like those on-chip watchdogs and Vcc monitors Responding to: ???'s previous message |
They suffer from noise, glitches and ground bounce on-die due to the lack of on-die Vcc decoupling and, especially tragical, suffer from manufacturing tolerances of "Vbad"-thresholds. Also, they seldom work down to Vcc=0V. These thingys often are crap, even if the manufacurer is Silabs or whosoever: What helps a brown-out detector, which can only reset the micro, when first a SFR has to be written to "1"?? Datasheet make believe that these solutions will work, but in reality they fail just too often.
Its perfect, that the MAX1232 contains a watchdog, which needs to be fed. A full off-chip solution! Kai |
| Topic | Author | Date |
| AT89C51ED2 changing speed on its own | 01/01/70 00:00 | |
| apply proper reset | 01/01/70 00:00 | |
| apply proper reset | 01/01/70 00:00 | |
| then that's R0 not R1 | 01/01/70 00:00 | |
| MAX1232 + 4k7 pull-up | 01/01/70 00:00 | |
| I beliebe this chip has a built-in watchdog and thus ... | 01/01/70 00:00 | |
| I don't like those on-chip watchdogs and Vcc monitors | 01/01/70 00:00 | |
| Should be always on | 01/01/70 00:00 | |
| external vs internal | 01/01/70 00:00 | |
| .. | 01/01/70 00:00 | |
| Ground plane? | 01/01/70 00:00 | |
| no ground plane | 01/01/70 00:00 | |
| choose a "magic" frequency crystal ... | 01/01/70 00:00 | |
20MHz and 57600 | 01/01/70 00:00 |