Typical Applications - Epson Power Supply IC S1F70000 Technical Manual

V circuit
O
PWCR
RST
Output voltage response compensation
The S1F76380 series are provided with a response com-
pensation input. A response compensation capacitor is
connected between V
CONT
voltage generated by the boosted output voltage to be
suppressed to a minimum.
Standby mode and battery backup
The S1F76310 series are equipped with a standby
mode, initiated by connecting PS to GND.

TYPICAL APPLICATIONS

Example Circuits
The output current, I , and power conversion effi-
O
ciency, Peff of a particular device in a series depends on
S1F76310 series
L
V
I1
V
I2
S1F76310M/C
GND
PS RST
S1F70000 Series
Technical Manual
V circuit
I1
V
I1
–
+
and V , allowing the ripple
O
D
V
SW
V
O
PWCR
C1
R1
EPSON
In standby mode, the booster, including the crystal os-
cillator, is disabled (the switching transistor used to
drive the inductor is turned OFF) and the built-in
backup switch is turned ON, so that the input voltage at
V is output at V . This enables the battery backup
I2 O
function. PS is pulled-up internally, so when standby
mode is not required, the pin should be left open.
Powering up
Ensure that V is at least the minimum operating volt-
O
age (0.9V) before switching on the booster circuit.
One way to do this is to attach a battery so that V
drops below the minimum required for backup mode. If
no such external power supply is available, connect V
to V and hold PS Low when applying power for the
I1
first time.
Battery
PS
C
factors such as the switching frequency, type of coil,
and the size and type of other external components.
S1F76380 series
L
V
I1
S1F76380M/C
GND
PWCR PS
S1F76300 Series
never
O
I2
V
I2
S1F76310M
D
V
SW
V
O
V
CONT
C1
RST
4–15