Epson S1F70000 Power Supply User Manual


 
S1F71200 Series
S1F70000 Series EPSON 4–41
Technical Manual
S1F71200
Series
DESCRIPTION
S1F71200 is a step-up/step-down DC/DC converter
control IC for which the CMOS process is used and to
which a power transistor is connected outside.
S1F71200 is composed of an oscillator, a reference
voltage circuit, an error amplifier, a PWM circuit, a se-
ries regulator, a driver, etc. When this IC drives an ex-
ternal power transistor, S1F71200 can constitute a step-
up/step-down DC/DC converter that operates as a [step-
down] series regulator when the input voltage is High
and that operates as a [step-up] switching regulator of
pulse width modulation system (PWM) when the input
voltage is Low.
S1F71200 is also provided with an overcurrent protec-
tion circuit and a soft start circuit. When receiving ex-
ternal signals, S1F71200 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 sys-
tem halt.
FEATURES
Input voltage : 2.5V to 12.0V
Output voltage : 5.0V (S1F71200M0A0)
3.3V (S1F71200M0B0)
Power off current : 1.0µA
Self current consumption : 150µA
(step-up portion)
15µA
(step-down portion)
Frequency fixing (200kHz) PWM at step-up time
Power off function (IC shutdown)
Soft start function
Overcurrent protection function
Shipping pattern : plastic package
(SSOP2-16 pin)
* Radiation-resistant design has not been provided for
this specification.
S1F71200 Series PWM Type Step-up/down DC/DC
Switching Regulator