LM7809
The LM7809 is a popular positive voltage regulator IC that belongs to the 78xx series. It is designed to provide a stable 9-volt output voltage from a fluctuating input voltage. This makes it useful for applications where a consistent 9V supply is required, even if the input power source varies. The LM7809 is a three-terminal device, typically housed in a TO-220 package, and requires minimal external components for operation, usually just an input and an output capacitor for stability.
Key features of the LM7809 include built-in thermal shutdown and current limiting capabilities, which protect the