L78S05 STMICROELECTRONICS [STMicroelectronics], L78S05 Datasheet - Page 18

• Manufacturer Part Number: L78S05
• Description: 2A POSITIVE VOLTAGE REGULATORS
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

L78S00 SERIES
Figure 32 : Light Controllers (V
= V
+ V
).
o min
xx
BE
V
falls when the light goes up
V
rises when the light goes up
O
O
Figure 33 : Protection against Input Short-circuit
with High Capacitance Loads.
Applications with high capacitance loads and an
output voltage greater than 6 volts need an external
diode (see fig. 33) to protect the device against input
short circuit. In this case the input voltage falls
rapidly while the output voltage decreases showly.
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 tran-
sistor may be destroyed. The external diode by-
passes the current from the IC to ground.
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