Filterless High Efficiency Mono 3 W Class-D Audio Amplifier SSM2317 supply. It is capable of delivering 3 W of continuous output FEATURES power with <1% THD + N driving a 3 load from a 5.0 V supply. Filterless Class-D amplifier with - modulation Automatic level control (ALC) improves dynamic range and The SSM2317 features a high efficiency, low noise modulation prevents clipping scheme that does not require any external LC output filters. The 3 W into 3 load and 1.4 W into 8 load at 5.0 V supply modulation continues to provide high efficiency even at low output with <10% total harmonic distortion (ALC off) power. It operates with 93% efficiency at 1.4 W into 8 or 85% 700 mW into 8 load at 4.2 V supply (ALC 80%) efficiency at 3 W into 3 from a 5.0 V supply and has an SNR of 93% efficiency at 5.0 V, 1.4 W into 8 speaker >93 dB. Spread-spectrum pulse density modulation is used to >93 dB signal-to-noise ratio (SNR) provide lower EMI radiated emissions compared with other Single-supply operation from 2.5 V to 5.5 V Class-D architectures. 20 nA ultralow shutdown current Automatic level control (ALC) can be activated to suppress Short-circuit and thermal protection clipping and improve dynamic range. This feature only requires Available in 9-ball, 1.5 mm 1.5 mm WLCSP one external resistor tied to GND via the VTH pin and an Pop-and-click suppression activation voltage on the ALC EN pin. Built-in resistors reduce board component count Default fixed 18 dB or user-adjustable gain setting The SSM2317 has a micropower shutdown mode with a typical shutdown current of 20 nA. Shutdown is enabled by applying APPLICATIONS a logic low to the SD pin. Mobile phones MP3 players The device also includes pop-and-click suppression circuitry. This Portable gaming minimizes voltage glitches at the output during turn-on and turn- Portable electronics off, reducing audible noise on activation and deactivation. Educational toys The default gain of the SSM2317 is 18 dB, but users can reduce the GENERAL DESCRIPTION gain by using a pair of external resistors (see the Gain section). The SSM2317 is a fully integrated, high efficiency, Class-D audio The SSM2317 is specified over the commercial temperature range amplifier. It is designed to maximize performance for mobile of 40C to +85C. It has built-in thermal shutdown and output phone applications. The application circuit requires a minimum short-circuit protection. It is available in a 9-ball, 1.5 mm 1.5 mm of external components and operates from a single 2.5 V to 5.5 V wafer level chip scale package (WLCSP). FUNCTIONAL BLOCK DIAGRAM VBATT 10F 2.5V TO 5.5V 0.1F VDD SSM2317 1 80k 0.1F 10k IN+ AUDIO IN+ OUT+ MODULATOR FET (- ) DRIVER OUT 1 0.1F 10k IN AUDIO IN 80k SD INTERNAL POP-AND-CLICK SHUTDOWN BIAS ALC OSCILLATOR SUPPRESSION GND ALC EN VTH R TH ALC ENABLE 1 INPUT CAPACITORS ARE OPTIONAL IF INPUT DC COMMON-MODE VOLTAGE IS APPROXIMATELY V /2. DD Figure 1. Rev. A 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 2008 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. 07242-001SSM2317 TABLE OF CONTENTS Features .............................................................................................. 1 Gain .............................................................................................. 14 Applications ....................................................................................... 1 Pop-and-Click Suppression ...................................................... 14 General Description ......................................................................... 1 Output Modulation Description .............................................. 14 Functional Block Diagram .............................................................. 1 Layout .......................................................................................... 14 Revision History ............................................................................... 2 Input Capacitor Selection .......................................................... 15 Specif icat ions ..................................................................................... 3 Proper Power Supply Decoupling ............................................ 15 Absolute Maximum Ratings ............................................................ 5 Automatic Level Control (ALC) ............................................... 15 Thermal Resistance ...................................................................... 5 Operating Modes ........................................................................ 15 ESD Caution .................................................................................. 5 Attack Time, Hold Time, and Release Time ........................... 15 Pin Configuration and Function Descriptions ............................. 6 Output Threshold ....................................................................... 16 Typical Performance Characteristics ............................................. 7 Enable/Disabling ALC ............................................................... 16 Typical Application Circuits .......................................................... 13 Outline Dimensions ....................................................................... 17 Theory of Operation ...................................................................... 14 Ordering Guide .......................................................................... 17 O ver vie w ...................................................................................... 14 REVISION HISTORY 6/08Rev. 0 to Rev. A Changes to Figure 1 .......................................................................... 1 Changes to Table 2 ............................................................................ 5 Changes to Figure 17 and Figure 18 ............................................... 9 Changes to Figure 39 and Figure 40 ............................................. 13 Changes to Ordering Guide .......................................................... 17 3/08Revision 0: Initial Version Rev. A Page 2 of 20