LM78XX Series Voltage Regulators
May 2000
LM78XX Series Voltage Regulators
General Description
The LM78XX series of t...
LM78XX Series
Voltage Regulators
May 2000
LM78XX Series
Voltage Regulators
General Description
The LM78XX series of three terminal regulators is available with several fixed output
voltages making them useful in a wide range of applications. One of these is local on card regulation, eliminating the distribution problems associated with single point regulation. The
voltages available allow these regulators to be used in logic systems, instrumentation, HiFi, and other solid state electronic equipment. Although designed primarily as fixed
voltage regulators these devices can be used with external components to obtain adjustable
voltages and currents.
The LM78XX series is available in an aluminum TO-3 package which will allow over 1.0A load current if adequate heat sinking is provided. Current limiting is included to limit the peak output current to a safe value. Safe area protection for the output transistor is provided to limit internal power dissipation. If internal power dissipation becomes too high for the heat sinking provided, the thermal shutdown circuit takes over preventing the IC from overheating.
Considerable effort was expanded to make the LM78XX series of regulators easy to use and minimize the number of external components. It is not necessary to bypass the out-
put, although this does improve transient response. Input bypassing is needed only if the regulator is located far from the filter capacitor of the power supply.
For output
voltage other than 5V, 12V an...