The power supply accepts 8 to 16 volts and produces 12 volts. The topology is SEPIC (single-ended primary inductance converter), the advantage being the ability to convert up or down with a minimum of parts and maximum efficiency. […] the power supply is good for about 8 amps output and can power the system while starting the car.
The UC3843 chip is very common and made by many manufacturers using slightly different numbering systems. It comes in an 8 pin DIP package, but I only had 14 pin SOP versions so I used a DIP header and hacked it in. Three type of protection are incorporated in the design. First is a 6 amp
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