Compact, 600 mA, 3 MHz, Step-Down DC-to-DC Converter Data Sheet ADP2108 FEATURES GENERAL DESCRIPTION Peak efficiency: 95% The ADP2108 is a high efficiency, low quiescent current step- 3 MHz fixed frequency operation down dc-to-dc converter manufactured in two different Typical quiescent current: 18 A packages. The total solution requires only three tiny external Maximum load current: 600 mA components. It uses a proprietary, high speed current mode, Input voltage: 2.3 V to 5.5 V constant frequency PWM control scheme for excellent stability Uses tiny multilayer inductors and capacitors and transient response. To ensure the longest battery life in Current mode architecture for fast load and line portable applications, the ADP2108 has a power save mode that transient response reduces the switching frequency under light load conditions. 100% duty cycle low dropout mode The ADP2108 runs on input voltages of 2.3 V to 5.5 V, which Internal synchronous rectifier allows for single lithium or lithium polymer cell, multiple alkaline Internal compensation or NiMH cell, PCMCIA, USB, and other standard power sources. Internal soft start The maximum load current of 600 mA is achievable across the Current overload protection input voltage range. Thermal shutdown protection The ADP2108 is available in fixed output voltages of 3.3 V, 3.0 V, Shutdown supply current: 0.2 A 2.5 V, 2.3 V, 1.82 V, 1.8 V, 1.5 V, 1.3 V, 1.2 V, 1.1 V, and 1.0 V. All Available in versions include an internal power switch and synchronous rect- 5-ball WLCSP ifier for minimal external part count and high efficiency. The 5-lead TSOT ADP2108 has an internal soft start and is internally compensated. Supported by ADIsimPower design tool During logic controlled shutdown, the input is disconnected APPLICATIONS from the output and the ADP2108 draws less than 1 A from PDAs and palmtop computers the input source. Wireless handsets Other key features include undervoltage lockout to prevent deep Digital audio, portable media players battery discharge and soft start to prevent input current over- Digital cameras, GPS navigation units shoot at startup. The ADP2108 is available in 5-ball WLCSP and 5-lead TSOT packages. The ADP2109 provides the same features and operations as the ADP2108 and has the additional function of a discharge switch in the WLCSP package. TYPICAL APPLICATIONS CIRCUIT ADP2108 1H 2.3V TO 5.5V 1.0V TO 3.3V SW VIN 4.7F 10F ON OFF EN FB GND Figure 1. Rev. H Document Feedback Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 20082014 Analog Devices, Inc. All rights reserved. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Technical Support www.analog.com Trademarks and registered trademarks are the property of their respective owners. 07375-003ADP2108 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Enable/Shutdown ....................................................................... 11 Applications ....................................................................................... 1 Short-Circuit Protection ............................................................ 12 General Description ......................................................................... 1 Undervoltage Lockout ............................................................... 12 Typical Applications Circuit ............................................................ 1 Thermal Protection .................................................................... 12 Revision History ............................................................................... 2 Soft Start ...................................................................................... 12 Specifications ..................................................................................... 3 Current Limit .............................................................................. 12 Absolute Maximum Ratings ............................................................ 4 100% Duty Operation ................................................................ 12 Thermal Resistance ...................................................................... 4 Applications Information .............................................................. 13 ESD Caution .................................................................................. 4 ADIsimPower Design Tool ....................................................... 13 Pin Configuration and Function Descriptions ............................. 5 External Component Selection ................................................ 13 Typical Performance Characteristics ............................................. 6 Thermal Considerations ............................................................ 14 Theory of Operation ...................................................................... 11 PCB Layout Guidelines .............................................................. 14 Control Scheme .......................................................................... 11 Evaluation Board ............................................................................ 15 PWM Mode ................................................................................. 11 Outline Dimensions ....................................................................... 16 Power Save Mode ........................................................................ 11 Ordering Guide .......................................................................... 17 REVISION HISTORY 6/14Rev. G to Rev. H 4/09Rev. B to Rev. C Updated Outline Dimensions ....................................................... 16 Changes to General Description Section ....................................... 1 6/12Rev. F to Rev. G 2/09Rev. A to Rev. B Change to Features Section ............................................................. 1 Added 5-Lead TSOT Package ........................................... Universal Added ADIsimPower Design Tool Section ................................. 13 Changes to Absolute Maximum Ratings Section .......................... 4 Updated Outline Dimensions ....................................................... 16 Updated Outline Dimensions ....................................................... 16 Changes to Ordering Guide .......................................................... 17 1/12Rev. E to Rev. F 11/08Rev. 0 to Rev. A Change to Table 3................................................................................... 4 Changes to Output Capacitor Section ......................................... 13 Changes to Figure 4 ........................................................................... 6 Updated Outline Dimensions ....................................................... 16 10/10Rev. D to Rev. E 9/08Revision 0: Initial Version Changed 40C to +85C to 40C to +125C Throughout ......... 3 Changes to Ordering Guide .......................................................... 17 1/10Rev. C to Rev. D Changes to Ordering Guide .......................................................... 17 Rev. H Page 2 of 20