SC633 Datasheet, PDF (1/15 Pages) Semtech Corporation – Fixed 5.3V Output Charge Pump Regulator

POWER MANAGEMENT
Features
 Input voltage range — 2.9V to 5.5V
 V_OUT tolerance — 5.3V ±3%
 Continuous output current — 275mA, V_IN=3V
 Peak output current — 400mA
 Three charge pump modes — 1x, 1.5x and 2x
 Output ripple ≤ 40mV_PP for I_OUT ≤ 400mA
 Short circuit, over-voltage, and over-temperature
protection
 Soft-start functionality
 Shutdown current — 0.1µA, typical
 Ultra thin package — 2 x 2 x 0.6 (mm)
 Lead-free and halogen-free
 WEEE and RoHS compliant
Applications
 Mobile phones
 MP3 players
 USB On-The-Go
 Multi-LED backlit LCDs
 Compact flash/CF+ products
 PMPs
 Digital video cameras
 Digital still cameras
 PDAs
SC633
Fixed 5.3V Output
Charge Pump Regulator
Description
The SC633 is a high-current voltage regulator using
Semtech’s proprietary low-noise charge pump technol-
ogy. Performance is optimized for use in single Li-Ion
battery cell applications. The regulator provides the per-
formance of a linear, low drop-out (LDO) voltage regulator
when the input is greater than 5.3V. Unlike an LDO, drop-
out is avoided when the input is less than 5.3V. Instead, a
charge pump is activated to provide voltage boost and
the head-room needed for voltage regulation.
Only two 2.2µF bucket capacitors are required to deliver
the full output current. The charge pump provides a low
EMI solution compared to inductive boost regulators.
The SC633’s charge pump has three modes of operation:
2x, 1.5x, and 1x modes. The 2x and 1.5x modes deliver
current to the load in each of two phases. The 1x mode
turns off the charge pump, delivering current through an
LDO. When active, the charge pump provides low-ripple
operation at 200kHz, which is typically less than 30mVpp
at the output. The SC633 is capable of delivering 275mA
continuous current, with peak current to 400mA. A 22µF
output capacitor is used for decoupling the load and for
smoothing mode transitions. Hysteresis is provided to
prevent chatter between charge pump modes.
Typical Application Circuit
V_BAT
C _IN
IN
2 2 µF
OUT
V_OUT = 5.3V @ 275mA
C_OUT
2 2 µF
SC633
C h ip
enable
EN
C1+
C1-
C2+
GND
C2-
C₁
2 .2 µF
C₂
2 .2 µF
Rev 2.0
US Patent: 7,808,220