SC630A Datasheet, PDF (1/15 Pages) Semtech Corporation – 1MHz Fixed 3.3V Output Charge Pump Regulator

POWER MANAGEMENT
Features
 Input voltage range — 2.95V to 5.5V
 V_OUT tolerance — 3.3V ±3%
 Continuous output current — 300mA max
 Three charge pump modes — 1x, 1.5x and 2x
 Output ripple voltage — 33mV_PP , typical
 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
 Tablets
 USB On-The-Go
 Multi-LED backlit LCDs
 Compact flash/CF+ products
 Digital video cameras
 DVI/HDMI ports
 Wi-Fi base stations
 Modems
 Set-top boxes
SC630A
1MHz Fixed 3.3V Output
Charge Pump Regulator
Description
The SC630A is a high-current voltage regulator using
Semtech’s proprietary low-noise charge pump technol-
ogy. The charge pump provides a low EMI solution
compared to inductive boost regulators. Performance is
optimized for use in single Li-Ion battery cell applications.
The regulator provides the performance of a linear, low
drop-out (LDO) voltage regulator when the battery is
greater than 3.3V. Unlike an LDO, drop-out is avoided
when the battery is less than 3.3V. Instead, a charge pump
is activated to provide voltage boost and the head-room
needed for regulation.
The SC630A’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. Hysteresis is provided to prevent chatter between
charge pump modes. When active, the charge pump pro-
vides low-ripple operation at 1MHz. Typically the output
ripple is 1% of the output voltage — 33mVpp at 215mA.
A small 2.2µF capacitor is recommended for all four capaci-
tors. The full rated output current is provided when 2.2µF
is used for both bucket capacitors. At the output, a 2.2µF
capacitor decouples the load and provides smoothing for
mode transitions, while another 2.2µF is used to decouple
the input.
Typical Application Circuit
V_BAT
C_IN
IN
2.2µF
OUT
V_OUT = 3.3V @ 300mA
C_OUT
2.2µF
SC630A
Chip
enable
EN
C1+
C1-
C2+
GND
C2-
C₁
2.2µF
C₂
2.2µF
Rev. 1.1
© 2011 Semtech Corporation
US Patent: 7,808,220