SC195B Datasheet, PDF (1/19 Pages) Semtech Corporation – 3.5MHz, 500mA Synchronous Step Down DC-DC Regulator

POWER MANAGEMENT
Features
 Input Voltage — 2.9V to 5.5V
 Output Voltage — 0.8V to 3.6V
 Output current capability — 500mA
 Efficiency up to 94%
 15 Programmable output voltages
 High light-load efficiency via automatic PSAVE mode
 Fast transient response
 Temperature range — -40 to +85°C
 Oscillator frequency — 3.5MHz
 100% duty cycle capability
 Quiescent current — 38µA typ
 Shutdown Current — 0.1µA typ
 Internal soft-start
 Over-voltage protection
 Current limit and short circuit protection
 Over-temperature protection
 Under-voltage lockout
 Floating control pin protection
 WLCSP8-0.80 X 0.80 X 0.375 (mm) package
 Pb free, halogen free, and RoHS/WEEE compliant
Applications
 Smart phones and cellular phones
 MP3/Personal media players
 Personal navigation devices
 Digital cameras
 Single Li-ion cell or 3 NiMH/NiCd cell devices
 Devices with 3.3V or 5V internal power rails
SC195B
3.5MHz, 500mA Synchronous
Step Down DC-DC Regulator
Description
The SC195B is a high efficiency, 500mA step down regula-
tor designed to operate with an input voltage range of
2.9V to 5.5V. The input voltage range makes it ideal for
battery operated applications with space limitations. The
SC195B also includes fifteen programmable output
voltage settings that can be selected using the four
control pins, eliminating the need for external feedback
resistors. The output voltage can be fixed to a single
setting or dynamically switched between different levels.
Pulling all four control pins low disables the output and
puts the device into a low current shutdown state.
The SC195B operates at a fixed 3.5MHz switching fre-
quency in normal PWM (Pulse-Width Modulation) mode.
A variable frequency PSAVE (power-save) mode is used to
optimize efficiency at light loads for each output setting.
Built-in hysteresis prevents chattering between the two
modes.
The SC195B provides several protection features to safe-
guard the device under stressed conditions. These
include short circuit protection, over-temperature protec-
tion, over-voltage protection, under-voltage lockout, and
soft-start to control in-rush current. These features
coupled with the small 8-bump 0.80 X 0.80 X 0.375 (mm)
package make it a versatile device ideal for step-down
regulation in products needing high efficiency and a
small PCB footprint.
Typical Application Circuit
V_IN
2.9V to 5.5V
Control Logic
(May also be
hard wired to
V_IN/ GND)
C_IN
4.7µF
SC195B
L1
1µH
V IN
LX
CTL3
CTL2
CTL1
CTL0
OUT
GND
V_OUT
0.8V to 3.6V
C_OUT
10µF
Rev 2.1
Semtech Corporation