| ??? 09/23/05 08:10 Read: times Msg Score: +1 +1 Good Answer/Helpful |
#101426 - Automotive Responding to: ???'s previous message |
Three main things to consider in automotive: temperature vibration noise As for EMI/EMC, there's plenty written by Intel and Freescale (nee Motorola) as a start. There's also SAE standards at a price. For the power supply, well don't consider it to be 12VDC! It has noise, drops, spikes etc. Also, the dreaded 'alternator dump' can put over 40V on the line. So your standard 7805 regulator is not a good choice unless you put some tough protection up front. For low current apps, I use a 10R 5W resistor and a 22V zener before my 7805 regulator. There are also regs specifically designed for automotive - LM2931 comes to mind. Any input - filter with R & C and software. Any Output - current limit - expect a short to 12V or to GND and it should survive. Stay away from electrolytic capacitors - vibration and temperature ensure these have a short life. All these apply to any microprocessor - be it 8051 or anything else. When you mention 'critical' - that suggests if it fails someone might get killed. This means you have to build in redundancy - never trust the micro to do what it is supposed to! The system must fail safe. Again, refer to the SAE for papers and standards. |
| Topic | Author | Date |
| 8051 in AUTOMOBILE | 01/01/70 00:00 | |
| 8051 is not popular in automotive | 01/01/70 00:00 | |
| 8051 | 01/01/70 00:00 | |
Hello | 01/01/70 00:00 | |
| Automotive | 01/01/70 00:00 | |
| MISRA? | 01/01/70 00:00 | |
| And this | 01/01/70 00:00 | |
| Humidity; thermal shock | 01/01/70 00:00 | |
| RF Problems | 01/01/70 00:00 | |
| Good points | 01/01/70 00:00 | |
| Data retention and load dump suppression | 01/01/70 00:00 | |
| for some apps GM requires 120 °C | 01/01/70 00:00 |