| ??? 01/18/08 16:09 Read: times |
#149704 - Apples and oranges Responding to: ???'s previous message |
Stefan said:
If my memory is ok, i remember in 32kHz circuit i mounted additional capacitor - in common R-Q point (where resistor and quartz are connected) to ground. In discrete circuits using MC14060, for instance, the output cap is often bigger than the input cap, if this is what you meant. Stefan said:
Thomas, You wrote 3mA / 12MHz for AT89C51.
I see [0.7xF(MHz)+3mA]- active mode, [0.6xF(MHz)+2mA]- idle mode in document for AT89C51AC2. This is kind of comparing apples and oranges. The AC2-variant is an entirely different chip, containing an ADC and other sections consuming a constant supply DC current. Also, if Thomas measured a supply current of 3mA at 12MHz, then he will be able to reduce it relevantly by choosing a much lower clock rate. It would be nice, if Thomas could come back to us and give us some more details about his project. May be we can find another way to reduce his current consumption... Kai |
| Topic | Author | Date |
| 32k xtal | 01/01/70 00:00 | |
| i did this with 89c2051 | 01/01/70 00:00 | |
| 470k series resistance needed | 01/01/70 00:00 | |
| ?additional capacitor | 01/01/70 00:00 | |
| Apples and oranges | 01/01/70 00:00 | |
...are not melons | 01/01/70 00:00 | |
| Low power modes | 01/01/70 00:00 | |
| since my consumption spec is "diesel oil" .... | 01/01/70 00:00 | |
| TI - are you sure? | 01/01/70 00:00 | |
| it was a while ago | 01/01/70 00:00 | |
| MSC121X | 01/01/70 00:00 | |
| that was what I remembered | 01/01/70 00:00 | |
| SiLabs better? | 01/01/70 00:00 |