I'm just about done a little battery powered LED "christmas light" project, which requires about a 12V power supply.
I know battery voltage drops a bit after some use long before they're considered "dead", so I was thinking of using a 12V regulator like a LM7812, and 10 D cells in serial instead of 8 D cells in serial. My thinking being that this should extend the "maximum brightness" period of the lights without burning them out with an excessive 15V.
Good idea, bad idea, or overkill? The light set is only 20 3mm LEDs which slowly change color (on their own), 4 parallel strings of 5 LEDs per string (w/4 resistors). My guess is that the LM might burn a little extra current, so it might be a little self defeating, but not sure whether that's significant.
I know battery voltage drops a bit after some use long before they're considered "dead", so I was thinking of using a 12V regulator like a LM7812, and 10 D cells in serial instead of 8 D cells in serial. My thinking being that this should extend the "maximum brightness" period of the lights without burning them out with an excessive 15V.
Good idea, bad idea, or overkill? The light set is only 20 3mm LEDs which slowly change color (on their own), 4 parallel strings of 5 LEDs per string (w/4 resistors). My guess is that the LM might burn a little extra current, so it might be a little self defeating, but not sure whether that's significant.