Sharp VL-C780S Serviceanleitung Seite 182

(c)
(d
—
(e)
(f)
{g)
VL-C780S/H/X
VL-C7400E
VL-C630S/H/x
VL-C6400£
Error amplifier
The error amplifier is a circuit to detect the output voltage of 5V and 9V regulator circuit. Equal-
phase input voltage of the error amplifier ranges from 1.05V to 1.45V, and reference voltage output
is divided by resistance and connected to respective inversion input terminal (pin (4) and pin (13)).
The output (pin (5) and pin (12)) terminal of the error amplifier connects a capacitor and resistance
to respective inversion input terminal, applying feedback. Also the output of the error amplifier is
connected to the inversion input of PWM comparator as well as to the detection circuit of the incor-
porated short-circuit protective circuit.
Low input malfunction prevention circuit
Output drive transistor
21