The LM342-XX series of three-terminal regulators are available with several fixed output voltages, making them useful in a wide range of applications. One of these is local regulation on the card, eliminating the single point of regulation associated with allocation issues. Allowable voltages for these to be used in systems for logic regulation, instrumentation, audio and other solid state electronics. Although designed primarily as fixed voltage regulators these devices can be used with external components to obtain adjustable voltage and current. The LM342-XX series are available in plastic TO-202 packages. This package allows these regulators to provide adequate heat dissipation if more than 0.25A is provided. A current limit is included to limit the peak output current to a safe value. Provides limited internal power dissipation for output transistor safe area protection. If the internal power dissipation is too high the heat supply sinks, a thermal shutdown circuit takes over, preventing the IC from overheating. Considerable effort has gone into making the LM342-XX series of regulators easy to use, minimizing the number of external components. It is not necessary to bypass the output, although this does improve transient response. The input needs to bypass the filter capacitor only when the regulator is far away from the supply. For output voltages below 5V, 12V and 15V other series of LM117 provide an output voltage range from 1.2V to 57V.

Features Output Current Excessive at 0.25A Internal Thermal Overload Protection No External Components Output Transistor Safe Zone Protection Internal Short-Circuit Current Limiting in Plastic TO-202 Package Special Circuit Allows Startup Even When Output Pulls Negative Voltage (gsupplies)