600mA 3MHz Synchronous

Step-Down DC-DC Converter

Preliminary Technical Data

ADP2102

Rev. PrA

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

responsibilityis assumedbyAnalogDevicesforitsuse,norforanyinfringements of patents or other

rightsofthirdpartiesthatmayresultfromitsuse.Specificationssubjecttochangewithoutnotice.No

license is granted by implication or otherwise under any patent or patent rights of Analog Devices.

Trademarksandregisteredtrademarksarethepropertyoftheirrespectiveowners.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781.329.4700

www.analog.com

Fax: 781.461.3113

©200

7 Analog Devices, Inc. All rights reserved.

FEATURES

95% peak efficiency

Optimized for low output voltages

Optimized for extremely small ceramic inductors

Up to 600mA, load current

2.7 V to 5.5 V input voltage range

Operates with a Single Li-Ion battery

Fixed Output Voltage from 0.8V to 1.875V

Adjustable Output Voltage from 0.8V to 1.875V

Low 60μA quiescent current

Internal Synchronous rectifier

3 MHz Operating Frequency

0.1μA Shutdown Supply Current

Small 8-Lead 3 x3 LFCSP Package

Enable /shutdown logic input

Under Voltage Lockout

Internal Soft Start

Internal Compensation

APPLICATIONS

Wireless Handsets

Portable Media Players

PDA’s and Palmtop Computers

Digital Cameras

Smart Phones

GENERAL DESCRIPTION

The ADP2102 is a low quiescent current step-down DC-DC

converter optimized to regulate low output voltages in a

compact 3mmx3mm LFCSP package. At high load currents, the

ADP2102 uses a current mode, constant on time, pseudo fixed

frequency, valley current control scheme for excellent stability

and transient response with very few, small external

components. To ensure the longest battery life in portable

applications, the ADP2102 has a power saving mode that

reduces the switching frequency under light load conditions to

significantly reduce the quiescent current.

The ADP2102 runs from input voltages from 2.7V to 5.5V

allowing single Li+/Li- polymer cell, multiple Alkaline/Ni-MH

cells and other standard power sources. ADP2102 output

voltage is adjustable from 0.8V to 1.875V, while the suffix part

numbers ADP2102-XX indicate pre-set voltage ranges of 1.875,

1.8, 1.5, 1.375, 1.25, 1.2, 1.0 & 0.8V. All versions include an

internal power switch and a synchronous rectifier for high

efficiency while internal compensation guarantees minimal

number of external components. During logic-controlled

shutdown, the input is disconnected from the output and it

draws less than 0.1μA from the input source. Other key features

include under voltage lockout to prevent deep battery discharge

and soft start to prevent input current overshoot at startup.

TYPICAL PERFORMANCE CHARACTERITICS

ADP2102_Efficiency

Vout= 1.375V L =2.2uH Cin= Cout = 10uF

60

70

80

90

100

0

100

200

300

400

500

600

Load Current ( mA)

Vin= 2.7V

Vin=3.0V

Vin=3.6V

Vin=4.2V

Figure 1.

TYPICAL APPLICATION CIRCUIT

Figure 2.