1 A, Low Dropout, CMOS Linear Regulator ADP1706/ADP1707/ADP1708 FEATURES TYPICAL APPLICATION CIRCUITS Maximum output current: 1 A ADP1706 10nF Input voltage range: 2.5 V to 5.5 V 1 EN SS 8 Low shutdown current: <1 A 2 GND SENSE 7 V = 3.3V OUT Low dropout voltage: 345 mV 1 A load 3 IN OUT 6 V = 5V IN 4 IN OUT 5 Initial accuracy: 1% 4.7F 4.7F Accuracy over line, load, and temperature: 2.5% 16 fixed output voltage options with soft start: 0.75 V to 3.3 V (ADP1706) Figure 1. ADP1706 with Fixed Output Voltage, 3.3 V 16 fixed output voltage options with tracking ADP1707 0.75 V to 3.3 V (ADP1707) V 1 EN TRK 8 TRK Adjustable output voltage option: 2 GND SENSE 7 0.8 V to 5.0 V (ADP1708) V 3 IN OUT 6 OUT V = 5V IN Stable with small 4.7 F ceramic output capacitor 4 IN OUT 5 Excellent load/line transient response 4.7F 4.7F V (V) Current limit and thermal overload protection OUT Logic-controlled enable 3 2 Available in an 8-lead, exposed paddle SOIC and 1 3 mm 3 mm, 8-lead exposed paddle LFCSP 0 123 45 V (V) TRK APPLICATIONS Figure 2. ADP1707 with Output Voltage Tracking Notebook computers Memory components ADP1708 R2 Telecommunications equipment 1 EN ADJ 8 R1 Network equipment 2 GND SENSE 7 V = 0.8V(1 + R1/R2) OUT 3 6 DSP/FPGA/microprocessor supplies V = 5V IN OUT IN 4 IN OUT 5 Instrumentation equipment/data acquisition systems 4.7F 4.7F Figure 3. ADP1708 with Adjustable Output Voltage, 0.8 V to 5.0 V GENERAL DESCRIPTION ADP1707 and ADP1708 contain internal soft start capacitors The ADP1706/ADP1707/ADP1708 are CMOS, low dropout that give a typical start-up time of 100 s. The ADP1707 linear regulators that operate from 2.5 V to 5.5 V and provide includes a tracking feature that allows the output to follow an up to 1 A of output current. Using an advanced proprietary external voltage rail or reference. architecture, they provide high power supply rejection and achieve excellent line and load transient response with a small The ADP1706/ADP1707/ADP1708 are available in an 8-lead, 4.7 F ceramic output capacitor. exposed paddle SOIC package and an 8-lead, 3 mm 3 mm exposed paddle LFCSP, making them not only very compact The ADP1706/ADP1707 are available in 16 fixed output volt- solutions but also providing excellent thermal performance for age options. The ADP1708 is available in an adjustable version, applications requiring up to 1 A of output current in a small, which allows output voltages that range from 0.8 V to 5.0 V via low profile footprint. an external divider. The ADP1706 allows an external soft start capacitor to be connected to program the start-up time the Rev. 0 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 www.analog.com license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Fax: 781.461.3113 2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. 06640-003 06640-001 06640-002ADP1706/ADP1707/ADP1708 TABLE OF CONTENTS Soft Start Function (ADP1706) ................................................ 10 Features .............................................................................................. 1 Adjustable Output Voltage (ADP1708)................................... 11 Applications....................................................................................... 1 Track Mode (ADP1707) ............................................................ 11 Typical Application Circuits............................................................ 1 Enable Feature ............................................................................ 11 General Description ......................................................................... 1 Application Information................................................................ 12 Revision History ............................................................................... 2 Capacitor Selection .................................................................... 12 Specifications..................................................................................... 3 Voltage Tracking Applications.................................................. 12 Absolute Maximum Ratings............................................................ 5 Current Limit and Thermal Overload Protection ................. 12 Thermal Resistance ...................................................................... 5 Thermal Considerations............................................................ 13 ESD Caution.................................................................................. 5 PCB Layout Considerations...................................................... 15 Pin Configurations and Function Descriptions ........................... 6 Outline Dimensions....................................................................... 16 Typical Performance Characteristics ............................................. 7 Ordering Guide .......................................................................... 17 Theory of Operation ...................................................................... 10 REVISION HISTORY 6/07Revision 0: Initial Version Rev. 0 Page 2 of 20