AME5251 Datasheet, PDF (1/19 Pages) Analog Microelectronics – Dual 1A, 1.5MHz Synchronous Step-Down Converter

AME
AME5251
n General Description
The AME5251 is a high efficiency monolithic synchro-
nous dual buck regulator using a constant frequency, cur-
rent mode architecture. Capable of delivering 1A output
cur-rent each channel over a wide input voltage range from
2.5V to 5.5V, the AME5251 is ideally suited for single Li-
Ion battery powered applications. 100% duty cycle pro-
vides low dropout operation, extending battery life in por-
table systems. Under light load conditions, the AME5251
operates in a power saving mode that consumes just
around 20µA of supply current, maximizing battery life in
portable applications.
The internal synchronous switch increases efficiency
and eliminates the need for an external Schottky diode.
Low output voltages are easily supported with the 0.6V
feedback reference voltage. The AME5251 is available
in small DFN-12A packages.
Other features include soft start, lower internal refer-
ence voltage with 2% accuracy, over temperature protec-
tion, and over current protection.
Dual 1A, 1.5MHz Synchronous
Step-Down Converter
n Features
l High Efficiency: Up to 95%
l Very Low 20µA Quiescent Current
l High Efficiency in Light Load Condition
l 2.5V to 5.5V Input Range
l Adjustable Output From 0.6V to V_IN
l Adjustable Output Voltage
l 1A Output Current Per Channel
l Low Dropout Operation: 100% Duty Cycle
l No Schottky Diode Required
l 1.5MHz Constant Frequency PWM Opera
tion
l Small DFN-12A Packages
l Green Products Meet RoHS Standard
n Applications
l Cellular Telephones
l Personal Information Appliances
l Wireless and DSL Modems
l MPS Players
l Portable Instruments
n Typical Application
VIN1
CIN2
R2
C1
VOUT1
COUT2
L2
VOUT2
AME5251
ON
OFF
IN2
EN2
SW2
NC2
R3
C2
GND
FB2
FB1
GND
R4
NC1
SW1
CIN1
R1
EN1
ON
OFF
IN1
VIN1
L1
COUT1
Rev.A.05
1