SC186 Datasheet, PDF (1/18 Pages) Semtech Corporation – 4A Synchronous Step-Down Regulator

POWER MANAGEMENT
SC186
4A Synchronous
Step-Down Regulator
Features
Description
 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
 Switching Frequency — 1.5MHz
 Automatic Power Save Mode
 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
 Routers and Network Cards
 LCD TV
 Office Automation
 Printers
The SC186 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 SC186 is optimized for maximum efficiency over a
wide range of load currents. During full load operation,
the device operates in PWM mode with fixed 1.5MHz
oscillator frequency, allowing the use of small surface
mount external components. As the load decreases, the
regulator will transition into Power Save mode maintain-
ing high efficiency.
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 SC186 is available in a thermally-enhanced, 3 x 3 x 0.6
(mm) MLPQ-UT16 package.
Typical Application Circuit
V_IN
CIN
22µF
RPGOOD
100kΩ
R_AVIN
1Ω
PVIN
LX
SC186
L
1.0µH
C_OUT
47µF
V_OUT
CTL0
CTL1
CTL2
CTL3
CAVIN
0.1µF
AVIN
PGOOD
CTL0
CTL1
CTL2
CTL3
VOUT
SS
C_SS
10nF
PGND
AGND
Revision 2.0
© 2011 Semtech Corporation