The more the voltage drop on LM317 high, the more it is hot. So I try using 2 Ic lm317 to decrease the voltage from 12V to 9V, then to 7V. After checking the circuit when I saw sometime it hot and sometime it cool. Is my solve ok? Thank you.
This is my board
2 IC at the top is used for LED diver circuit. The bottom is the low voltage circuit (12->9V ->7V)
This is my board
2 IC at the top is used for LED diver circuit. The bottom is the low voltage circuit (12->9V ->7V)