The LM7824 IC series of three terminal positive regulators are available in the TO-220 package and with several fixed output voltages, making them useful in a wide range of applications. Each type employs internal current limiting, thermal shut down and safe operating area protection, making it essentially indestructible. If adequate heat sinking is provided, they can deliver over 1A output current. Although designed primarily as fixed voltage regulators, these devices can be used with external components to obtain adjustable voltages and currents.
Design considerations of LM7824IC
The fixed voltage regulators in the LM7824 IC Series are built with features such as Output Transistor Safe Area Compensation, which lowers the output short circuit current as the voltage across the pass transistor increases, Thermal Overload Protection, which shuts down the circuit when it is subjected to an excessive power overload condition, Internal Short Circuit Protection, which caps the maximum current the circuit will pass, and Internal Short Circuit Protection.
Consensus is that compensating capacitors are not necessary in many low current applications.
However, if the regulator is connected to the power supply filter with lengthy wire lengths or if the output load capacitance is high, it is advised that the regulator input be bypassed by a capacitor.
To provide stable functioning under all load situations, a suitable high-frequency characteristic input bypass capacitor should be chosen. It is best to select a tantalum, mylar, or other capacitor with an internal impedance of less than 0.33 F at high frequencies. The bypass capacitor should be positioned immediately across the input terminals of the regulator with the shortest feasible leads. Since the regulator has no external sensing lead, proper building practises should be employed to reduce ground loops and lead resistance losses.