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MC79L05A / LM79L05A Rev. 1.1.0

3

Typical Application

Design Considerations

The MC79L05A / LC79L05A fixed-voltage regulators are designed with thermal overload protection that shuts down

the circuit when subjected to an excessive power overload condition. Internal short-circuit protection limits the maxi-

mum current the circuit will pass. In many low-current applications, compensation capacitors are not required. How-

ever, it is recommended that the regulator input be bypassed with a capacitor if the regulator is connected to the power

supply filter with long wire lengths, or if the output load capacitance is large. An input bypass capacitor should be

selected to provide good high-frequency characteristics to ensure stable operation under all load conditions. A 0.33

μF

or larger tantalum, mylar, or other capacitor having low internal impedance at high frequencies should be chosen. The

bypass capacitor should be mounted with the shortest possible leads directly across the regulator's input terminals.

Good construction techniques should be used to minimize ground loops and lead resistance drops since the regulator

has no external sense lead. Bypassing the output is also recommended.

A common ground is required between the input and the output voltages. The input voltage must remain typically 2.0 V

above the output voltage, even during the low point on the input ripple voltage.

Figure 2. Positive And Negative Regulator

Figure 3. Typical Application

LM78L05A

MC78L05A

LM79L05A

MC79L05A

I

MC79L05A

LM79L05A