L78 datasheet(29/55 Pages) STMICROELECTRONICS

부품명	L78

상세설명	Positive voltage regulator ICs

PDF	55 Pages

Scroll/Zoom	100%

제조업체	STMICROELECTRONICS [STMicroelectronics]

홈페이지	http://www.st.com

Logo

29 / 55 page

Figure 27. Light controllers (VO(min) = VXX + VBE)

VO rises when the light goes up

VO 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

L78 데이터시트(PDF) 29 Page - STMicroelectronics