Datasheet

Figure 27. Light controllers (V
O(min)
= V
XX
+ V
BE
)
V
O
rises when the light goes up
V
O
falls when the light goes up
GAMG220920161025MT
Figure 28. Protection against input short-circuit with high capacitance loads
GAMG220920161026MT
Note: Application with high capacitance loads and an output voltage greater than 6 volts need an external diode (see
Figure 23. Reducing power dissipation with dropping resistor) to protect the device against input short circuit. In
this case the input voltage falls rapidly while the output voltage decrease slowly. The capacitance discharges by
means of the base-emitter junction of the series pass transistor in the regulator. If the energy is sufficiently high,
the transistor may be destroyed. The external diode by-passes the current from the IC to ground.
L78
Design consideration
DS0422 - Rev 36
page 29/55