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ptk · 10-29-2004, 04:06 AM

Numberone
i guess you figure out the issues.
just in case

ITPS prevents over voltage. it doesn't not have the capability to prevent undervoltage. in addition, it does this at a price (voltage drop). it's common quoted at 0.6V drop, but in your case, seemed to be closer to 0.8V drop.

effectly, when your motor is not running, the input voltage will be that of the car batter... round about 12. so the output voltage will be below 12V.

your molex case most like comes with power supplys that doesn't regulate 12V, so your carputer won't be able to start when your 12V line is under voltage. even if they start, most likely will hang when load applies.

your tank circuit make sure your input never drops below 12V, hence allow the carputer to boot up. however, it still doesn't solve the issue of running the carputer when engine's off, coz you are basically running off your tank circuit which won't last you too long, depending on setup.

kao

10-29-2004, 04:06 AM	#8
ptk Variable Bitrate Join Date: Apr 2004 Location: Singapore Posts: 294	Numberone i guess you figure out the issues. just in case ITPS prevents over voltage. it doesn't not have the capability to prevent undervoltage. in addition, it does this at a price (voltage drop). it's common quoted at 0.6V drop, but in your case, seemed to be closer to 0.8V drop. effectly, when your motor is not running, the input voltage will be that of the car batter... round about 12. so the output voltage will be below 12V. your molex case most like comes with power supplys that doesn't regulate 12V, so your carputer won't be able to start when your 12V line is under voltage. even if they start, most likely will hang when load applies. your tank circuit make sure your input never drops below 12V, hence allow the carputer to boot up. however, it still doesn't solve the issue of running the carputer when engine's off, coz you are basically running off your tank circuit which won't last you too long, depending on setup. kao __________________ *** CarPC Ver 3 near completion.