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SC187 Datasheet, PDF (1/17 Pages) Semtech Corporation – 4A, 2.2MHz Synchronous Step-Down Regulator with 15 Preset Output Voltages
SC187
POWER MANAGEMENT
4A, 2.2MHz Synchronous Step-Down Regulator
with 15 Preset Output Voltages
Features
 Input Voltage Range — 2.9 to 5.5V
 Output Voltage Range — 0.8V to 3.3V
 Output Current — up to 4A
 Ultra-Small Footprint — <1mm Height Solution
 Minimum 1.8MHz Switching Frequency with no AM
Radio Band Interference
 Efficiency Up to 95%
 Low Output Noise Across Load Range
 Excellent Transient Response
 Start Up into Pre-Bias Output
 Duty-Cycle Low Dropout Operation — 100%
 Shutdown Current — <1µA
 Externally Programmable Soft Start Time
 Power Good indicator
 Input Under-Voltage Lockout
 Output Over-Voltage, Current Limit Protection
 Over-Temperature Protection
 Thermally Enhanced 3 x 3 x 0.6 (mm)
MLPQ-UT16 package
 Temperature Range — -40 to +85°C
 Lead-free, Halogen free, and RoHS/WEEE compliant
Applications
 Automotive Power Supplies
 Routers and Network Cards
 LCD TV
 Office Automation
Description
The SC187 is a 4A synchronous step-down regulator
designed to operate with an input voltage range of 2.9V
to 5.5V. The device offers fifteen pre-determined output
voltages via four control pins programmable from 0.8 to
3.3 Volts. The control pins allow for on-the-fly voltage
changes, enabling system designers to implement
dynamic power savings. The device is also capable of
adjusting output voltage via an external resistor divider.
The SC187 operates in PWM mode with fixed 2.2MHz
oscillator frequency, allowing the use of small surface
mount external components.
Connecting the control pins to logic low forces the device
into shutdown mode reducing the supply current to less
than 1μA. Connecting any of the control pins to logic high
enables the converter and sets the output voltage accord-
ing to Table 1. Other features include under-voltage
lockout, programmable soft-start to limit in-rush current,
power good indicator, over-temperature protection, and
output short circuit protection.
The SC187 is available in a thermally-enhanced, 3 x 3 x 0.6
(mm) MLPQ-UT16 package.
Typical Application Circuit
VIN
CIN
22µF
RPGOOD
100kΩ
RAVIN
1Ω
CAVIN
10nF
CTL0
CTL1
CTL2
CTL3
PVIN
LX
SC187
AVIN
PGOOD
CTL0
CTL1
CTL2
CTL3
VOUT
SS
CSS
10nF
PGND
AGND
L
1.0µH
COUT
47µF
VOUT
Rev 2.0