I am just starting to experiment a little with LEDs and have two projects in mind:
First, I have a white LED that is rated for 12V DC. I would like to use it as backlighting for a guage I am putting in my car. Since I intend to tie it into the dash light circuit to make it dimmable, what type of resistor can I use in series to prevent it from ever getting more than 12V. The voltage meter in the car shows voltages of 14 to 15 volts at times. The discription of the part says "... white LED with built-in resistors for 12Vdc, 12mA operation. No external resistor required. Works well on 4-12Vdc. Dimmer at lower voltages."
Second, I have some landscape lighting that is 12VAC. Since the light bulbs currently in the fixtures are standard wedge base type automotive bulbs, can I switch them to LED replacement bulbs. I know the LED replacement bulbs are intended for DC, will a diode in series solve the problem?
I know these are stupid simple questions for most of you, but I just recently learned how to program my VCR and now it is obsolete. Thanks.