| ??? 06/09/13 22:30 Read: times |
#189893 - Wrong how? Responding to: ???'s previous message |
Erik Malund said:
OK, but wrong. Time must be included in the calculation. E.g. a chip that runs twice as fast will allow twice the active mode current. Yes, but in this case I looked at the graphs in the datasheet. They list Icc at frequencies from 1 to 24MHz. At 2MHz the numbers are 0.6mA (idle) and 2.7mA (active), so I expected the actual current to be somewhere between the two. Where did I go wrong there? Why? 3V3 chips also have TTL output levels. Yes, but getting 5V from a 3V3 device is hard. I'm not driving a TTL input, but actually need 5V. But it looks like some Silabs devices run on 2.x volts internally, and can still do 5V I/O. IAP/JTAG seems a better solution Yes, if there's space. The common 10-pin headers are a no-go - there simply isn't that much space available. The devices that only need two pins for programming would be OK. The reason I chose DIL, is also assembly time. Soldering in a DIL device is a lot faster than the SMD devices (for me). A SOIC is not much worse, but anything smaller takes too long (when you may have a 100 boards to assemble). I have done a search for Silabs devices at the Mouser site, and it looks like 5V and SOIC are mutually exclusive options. But I may have overlooked something. I failed to mention in my first post, that my aim is less than 2mA. So I'm close already, but not close enough. Mikkel |
| Topic | Author | Date |
| Low-power MCU needed | 01/01/70 00:00 | |
| OK, but wrong | 01/01/70 00:00 | |
| Wrong how? | 01/01/70 00:00 | |
| Silabs options | 01/01/70 00:00 | |
| C8051F99x | 01/01/70 00:00 | |
| Silabs | 01/01/70 00:00 | |
| look it up | 01/01/70 00:00 | |
| Looked up | 01/01/70 00:00 | |
| f53, no | 01/01/70 00:00 | |
| C8051F537A is OK | 01/01/70 00:00 | |
| the current in active mode is not the issue | 01/01/70 00:00 | |
| Inactive current | 01/01/70 00:00 | |
| re: wrong | 01/01/70 00:00 | |
| Consumers | 01/01/70 00:00 | |
| Zilog Z51F0410 | 01/01/70 00:00 | |
| Zilog | 01/01/70 00:00 | |
| Check you are entering idle ? | 01/01/70 00:00 | |
| idle current | 01/01/70 00:00 | |
| Idle test | 01/01/70 00:00 | |
| re: | 01/01/70 00:00 | |
| It floats! It floats! | 01/01/70 00:00 | |
| re:floats | 01/01/70 00:00 | |
| re:floats | 01/01/70 00:00 | |
| Timers | 01/01/70 00:00 | |
| More idle tests | 01/01/70 00:00 | |
| Better regulator? | 01/01/70 00:00 | |
| LR8K4 450V regulator | 01/01/70 00:00 | |
| also try CLKREG | 01/01/70 00:00 | |
| Clk Dividers are a good idea | 01/01/70 00:00 | |
| No dividers | 01/01/70 00:00 | |
| LP52 is cheaper too... | 01/01/70 00:00 | |
| LP52 | 01/01/70 00:00 | |
| No GND pin? | 01/01/70 00:00 | |
| re:idle | 01/01/70 00:00 | |
| Totally idle | 01/01/70 00:00 | |
| Checks | 01/01/70 00:00 | |
| More checks | 01/01/70 00:00 | |
| Power Down ? | 01/01/70 00:00 | |
| test setup | 01/01/70 00:00 | |
| STC | 01/01/70 00:00 | |
| C8051F86x/85x ? | 01/01/70 00:00 | |
| Maybe not such a good choice, after all? | 01/01/70 00:00 | |
| Support? | 01/01/70 00:00 | |
'51 support | 01/01/70 00:00 |