SC120
POWER MANAGEMENT
Features
Input voltage — 0.7V to 4.5V
Minimum input startup voltage — 0.865V
Output voltage — fixed at 3.3V; adjustable from 1.8V
to 5.0V
Peak input current limit — 1.2A
Output current at 3.3 V — 80mA with V = 1.0V,
OUT
IN
190mA with V = 1.5V
IN
Efficiency up to 94%
Internal synchronous rectifier
Switching frequency — 1.2MHz
Automatic power save
Anti-ringing circuit
Operating supply current (measured at OUT) — 50μA
Shutdown current — 0.1μA (typ)
No forward conduction path during shutdown
Available in ultra-thin 1.5 × 2.0 × 0.6 (mm)
MLPD-UT-6 and SOT23-6 packages
Lead-free and halogen-free
WEEE and RoHS compliant
Applications
MP3 players
Smart Phones and cellular phones
Palmtop computers and handheld Instruments
PCMCIA cards
Memory cards
Digital cordless phones
Personal medical products
Wireless VoIP phones
Small motors
Typical Application Circuit
Low Voltage Synchronous
Boost Regulator
Description
The SC120 is a high efficiency, low noise, synchronous
step-up DC-DC converter that provides boosted voltage
levels in low-voltage handheld applications. The wide
input voltage range allows use in systems with single
NiMH or alkaline battery cells as well as in systems with
higher voltage battery supplies. It features an internal
1.2A switch and synchronous rectifier to achieve up to
94% efficiency and to eliminate the need for an external
Schottky diode. The output voltage can be set to 3.3V
with internal feedback, or to any voltage within the speci-
fied range using a standard resistor divider.
The SC120 operates in Pulse Width Modulation (PWM)
mode for moderate to high loads and Power Save Mode
(PSAVE) for improved efficiency under light load condi-
tions. It features anti-ringing circuitry for reduced EMI in
noise sensitive applications. Output disconnect capability
is included to reduce leakage current, improve efficiency,
and eliminate external components sometimes needed to
disconnect the load from the supply during shutdown.
Low quiescent current is obtained despite a high 1.2MHz
operating frequency. Small external components and the
space saving MLPD-UT-6, 1.5×2.0×0.6 (mm) package, or
low cost SOT23-6 package, make this device an excellent
choice for small handheld applications that require the
longest possible battery life.
L1
Single
Cell
(1.2V)
CIN
IN
EN
GND
LX
OUT
FB
SC120
3.3V
COUT
April 30, 2010
© 2010 Semtech Corporation
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