SC120_10 Datasheet, PDF (1/32 Pages) Semtech Corporation – Low Voltage Synchronous Boost Regulator

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)
C_IN
IN
EN
GND
LX
OUT
FB
SC120
3.3V
C_OUT
April 30, 2010
© 2010 Semtech Corporation
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