SC284 Datasheet, PDF (1/20 Pages) Semtech Corporation – Dual Channel 2.5MHz, 1.8A Synchronous Step-Down Regulator

SC284
Dual Channel 2.5MHz, 1.8A
POWER MANAGEMENT
Features
Synchronous Step-Down Regulator
Description
 V_IN Range — 2.9 – 5.5V
 V_OUT Selectable — 0.8 - 3.3V
 Up to 1.8A Output Current for Each Channel
 Ultra-Small Footprint, <1mm Height Solution
 Switching Frequency — 2.5MHz
 Efficiency Up to 94%
 Excellent Light Load Efficiency
 Low Output Noise Across Load Range
 Excellent Transient Response
 Start Up into Pre-Bias Output
 100% Duty-Cycle Low Dropout Operation
 Shutdown Current — <1µA
 Internal Soft Start
 Input Under-Voltage Lockout
 Output Over-Voltage, Current Limit Protection
 Over-Temperature Protection
 Adjustable Output Voltage
 Package — 3 x 3 x 0.6(mm) UT20
 Temperature Range — -40 to +85°C
 Lead-free, halogen-free, and RoHS/WEEE compliant
Applications
 Desktop Computing
 Set-Top Box
 LCD TV
 Network Cards
 Printer
The SC284 is a dual channel 1.8A synchronous step-
down regulator designed to operate with an input
voltage range of 2.9 to 5.5 Volts. Each channel 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
SC284 is also capable of adjusting the output voltage via
an external resistor divider.
The device operates with a fixed 2.5MHz oscillator
frequency, allowing the use of small surface mount
external components.
Connecting CTL0 — CTL3 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
according to Table 1. Other features include under-
voltage lockout, soft-start to limit inrush current, and
over-temperature protection.
The SC284 is available in a 3 x 3 x 0.6 (mm) MLPQ-UT20
package and has a rated temperature range of -40 to
+85°C.
Typical Application Circuit
V_INA
CINA
10µF
V_INB
C_INB
10µF
CTL0A
CTL1A
CTL2A
CTL3A
RAVINA 1Ω
CAVINA 10nF
RAVINB 1Ω
C_AVINB 10nF
PVINA
AVINA
LXA
VOUTA
AGNDA
LXB
VOUTB
SC284
PVINB
PGNDA
AVINB
AGNDB
PGNDB
CTL0A
CTL1A
CTL2A
CTL3A
CTL0B
CTL1B
CTL2B
CTL3B
LA 2.2µH
L_B 2.2µH
C_OUTA
22µF
C_OUTB
22µF
VOUTA
V_OUTB
CTL0B
CTL1B
CTL2B
CTL3B
Revision 2.0