| ??? 05/06/10 13:54 Read: times |
#175756 - Presumably because Responding to: ???'s previous message |
Erik Malund said:
Avoid SMD quartzes.
WHY, I have used 10.000s of such with no problems. Actually, Kai did give a reason - the full quote is (with my emphasis): Kai Klaas said:
Also, the resistance is the lower the bigger the quartz is!!! So, one remedy for you could be to take the good old HC-49/U instead of a smaller one. Avoid SMD quartzes. SMT devices do, in general, tend to be smaller than leaded ones - so this does suggest that one should, in general expect more ESR-related problems in SM crystals than leaded? But some SM crystals are identical to their leaded counterparts - only the terminations differ. So it might be more helpful to say, "Avoid miniature crystals" Erik said:
Now, I must say, I buy only known brands Good brands will, of course, take pains to ensure that their miniature crystals have adequate performance. But, as Kai suggests, that will be more difficult (ie, more expensive) than for "standard" sizes. So maybe the best advice would be, "only buy miniature crystals when they are of known high quality" - ie, not "cheap" (sic) ones! |
| Topic | Author | Date |
| Capacitor Value of MCS51 for Crystal | 01/01/70 00:00 | |
| What frequency? Fundamental or overtone? | 01/01/70 00:00 | |
| Reply to Kai Klass | 01/01/70 00:00 | |
| Equivalent series resistance is the critical parameter | 01/01/70 00:00 | |
| WHY? | 01/01/70 00:00 | |
| Of course!! | 01/01/70 00:00 | |
| Thanks to Erik, Kai and others | 01/01/70 00:00 | |
| Presumably because | 01/01/70 00:00 | |
| Oscillator frequency. | 01/01/70 00:00 | |
| Why not having a look into the datasheet? | 01/01/70 00:00 | |
| Thanks David Prentice | 01/01/70 00:00 | |
Your setup should include the micro... | 01/01/70 00:00 | |
| i had this problem before | 01/01/70 00:00 | |
| Reply to Arun Kumar | 01/01/70 00:00 | |
| may be this will help | 01/01/70 00:00 | |
| not necessarily | 01/01/70 00:00 | |
| Thanks Arun Kumar | 01/01/70 00:00 | |
| danger, danger | 01/01/70 00:00 | |
| Only the AT89S8253 is problematic! | 01/01/70 00:00 | |
| clarification appreciated | 01/01/70 00:00 | |
| I only recall the ones... | 01/01/70 00:00 | |
| with no interest ... | 01/01/70 00:00 | |
| Erik, you hurt me... | 01/01/70 00:00 | |
| no hurt intended | 01/01/70 00:00 |