I am building a charger for large (20-40 AH) lead acid batteries to power kid-size electric cars. I'm using an L200CV voltage regulator that's a step up from the 78XX, or LM317 types. It has 5 pins, and offers more control. Unfortunately, when I hooked it up to a battery in reverse polarity, I fried my L200CV. I decided to add a diode between the negative output and the battery, to avoid doing that dumbness twice. It happened again. How can that be? Shouldn' the diode on ONE output prevent the massive current flowing backwards that I caused? I've now put a 2nd diode on the positive output. NOW I'm safe--right?
Frying in Fresno, Bruce