regarding a power supply for a pic 12f629. a LM7805 is too big, im looking for something smaller. Is there a surface mount 7805? or is there another way to build a smaller circuit (im trying to get it all about the size of a nickel, maybe)
What's your input voltage, and how much current are you going to need? A zener diode and a resistor are good for basic situations as long as the voltage you're dropping isn't too large, less than the size of a dime.
What's your input voltage, and how much current are you going to need? A zener diode and a resistor are good for basic situations as long as the voltage you're dropping isn't too large, less than the size of a dime.
the voltage would be 12v with a 3 cell lipo battery. it will power a 12f629 flashing different light patters, it will then monitor the power supply and change flash patterns when it drops below 9.8 volts.
The 7805 needs a minimum input voltage of about 7.5V.
But a 9V alkaline battery's voltage drops quickly to 7.2V which is too low, then drops more to 6V.
A rechargable "9V" battery is frequently actually 7.2V.