Epson S1F70000 User Manual

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S1F70000 Series

Technical Manual

S1F71100 is a pulse width modulation (PWM) type
step-down DC/DC converter control IC for which the
CMOS process is used and to which a power transistor
is connected outside. S1F71100 is composed of an os-
cillator, a reference voltage circuit, an error amplifier, a
PWM circuit, a soft start circuit, a driver, etc. When this
IC drives an external P ch power MOS transistor,
S1F71100 can constitute a step-down DC/DC converter
that converts input voltages up to 12V into the output
voltage of 3.3V.
S1F71100 is also provided with a low-voltage protec-
tion circuit, an overcurrent protection circuit and a soft
start protection circuit. When receiving external sig-
nals, S1F71100 can stop the oscillator and the switching
circuit and turn off the power, so that it can reduce
wasteful current consumption at the time of system halt.

• Input voltage : 3.3V ~ 12V
• Output voltage : 3.3V (S1F71100M0A0)
• Power off current : 1

µ

A

• Self current consumption : 800

µ

A

• Frequency fixing (200kHz) PWM
• Power off function (IC shutdown)
• Soft start function
• Overcurrent protection function
• Low-voltage protection function
• Shipping pattern : plastic package SOP4-8pin
* Radiation-resistant design has not been provided for

this specification.

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–

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V

DD

POFFX

I

SENSE

SWO

V

SS

SSCAP

V

O

ERCAP

Low-voltage
protection circuit

Reference

voltage circuit

Soft start

Oscillator

PWM circuit

Error amplifier

Driver

Overcurrent

protection circuit

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