I need to use a LM7809 to reduce 12-14V to 9V , the device is using 40mA at normal state
when I search google for application circuit - I got all kind of valus for Cin , Cout. use this datasheet LM78xx datasheets
I saw in page 22 to use 0.33uF and 0.1uF - so can I use this ?
what is the thumb rule for it? and what is the formula I need to use?