Epson S1F70000 User Manual

S1F70000 Series

3–3

Technical Manual

S1F78100Y Series is a fixed positive output type volt-
age regulator of series regulator system and is fitted
with an output control MOS transistor between the in-
put and output pins as shown in the figure below.   The
voltage regulator feeds back voltages (V

REG

) divided

with the built-in resistors R

1

 and R

2

 connected between

V

DD

(2pin)

V

SS

(1pin)

V

O

(3pin)

R2

R1

V

REF

+

–

(V

REG

)

(Output control transistor)

(Operational amplifier)

the output pin (V

O 

pin) and the V

SS

 pin to compare

them with the reference voltage (V

REF

) and outputs the

stable output voltage (V

0

) not depending on input volt-

age by controlling the gate voltage of the output control
transistor.   The output voltage is fixed inside and is de-
cided with the following formula:

V

O  

=

R

1

+R

2

·V

REF

R

1