Original posted from
http://www.mitedu.freeserve.co.uk/Ci.../Power/ups.htm
Circuit : Andy Collinson
Email:
anc@mitedu.freeserve.co.uk ( I didnt design the circuit)
HI:
I have been looking for the alternative solution for the OPUS 150 Watt power supply since they told me to wait for three weeks.
I think alot of people want a UPS or PSU in their cars, that way we dunt need a shutdown controller for the computer and we dunt even have to wory about the ciritcal low voltage (8 ~10 volt) during the ignition.
So , this is what i have found on line, a Basic UPS circuit.
and here is my plan:
1)I will remove the western bridge since we only use that for AC inverter.
2)input is from the cigrate lighter (12 ~14Volt)
3)insert a 12 Volt UPS battery (from Ebay) at B1
4) add a DC-DC ITX or ATX power supply at V2
That way, if the power from cigrate lighter failed, 12 volt battery will keep supplying the power.
The good thing about this project is we dunt have to hook our power supply to the car battery and we dunt have to worry about the ciritcal voltage during the ignitation , and it is cheap
The down side about this project is I am not too sure how long will it take to fully charge the battery from the cigrate lighter, and there is no sign to tell you that the remaning left in the battery. I might be able to design an alarm circuit with LED indicator. And the most important thing. Since we are dealing with 5 amp or 6 amp current for our computers, I am not sure the current will heat up the component and burn the circuit.
I have been tested my circuit on the Pspice and it works on the simulation. Unfortuantely, I really dunt have any real hand experience and I'm wondering if any one can give me some advice here, thank you
Linear Mode
