Filterless High Efficiency Mono 1.4 W Class-D Audio Amplifier SSM2301 The SSM2301 operates with 85% efficiency at 1.4 W into 8 FEATURES from a 5.0 V supply and has a signal-to-noise ratio (SNR) that Filterless Class-D amplifier with - modulation is greater than 98 dB. Spread-spectrum modulation is used to No sync necessary when using multiple Class-D amplifiers provide lower EMI-radiated emissions compared with other from Analog Devices, Inc. Class-D architectures. 1.4 W into 8 at 5.0 V supply with less than 1% THD + N 85% efficiency at 5.0 V, 1.4 W into 8 speaker The SSM2301 has a micropower shutdown mode with a maximum Greater than 98 dB SNR (signal-to-noise ratio) shutdown current of 30 nA. Shutdown is enabled by applying Single-supply operation from 2.5 V to 5.0 V a logic low to the SD pin. 20 nA ultralow shutdown current Short-circuit and thermal protection The device also includes pop-and-click suppression circuitry. Available in 8-lead, 3 mm 3 mm LFCSP and MSOP packages This minimizes voltage glitches at the output during turn-on Pop-and-click suppression and turn-off, thus reducing audible noise on activation and Built-in resistors reduce board component count deactivation. Fixed and user-adjustable gain configurations The fully differential input of the SSM2301 provides excellent APPLICATIONS rejection of common-mode noise on the input. Input coupling Mobile phones capacitors can be omitted if the dc input common-mode voltage MP3 players is approximately VDD/2. Portable gaming Portable electronics The SSM2301 also has excellent rejection of power supply noise, Educational toys including noise caused by GSM transmission bursts and RF rectification. PSRR is typically 63 dB at 217 Hz. GENERAL DESCRIPTION The SSM2301 is a fully integrated, high efficiency, Class-D audio The gain can be set to 6 dB or 12 dB by utilizing the gain control amplifier designed to maximize performance for mobile phone select pin connected respectively to ground or to VDD. Gain applications. The application circuit requires a minimum of can also be adjusted externally by inserting a resistor in series external components and operates from a single 2.5 V to 5.0 V with each input pin. supply. It is capable of delivering 1.4 W of continuous output The SSM2301 is specified over the commercial temperature range power with less than 1% THD + N driving an 8 load from (40 C to +85 C). It has built-in thermal shutdown and output a 5.0 V supply. short-circuit protection. It is available in both an 8-lead, 3 mm The SSM2301 features a high efficiency, low noise modulation 3 mm lead-frame chip scale package (LFCSP) and an 8-lead scheme that does not require external LC output filters. The modu- MSOP package. lation provides high efficiency even at low output power. FUNCTIONAL BLOCK DIAGRAM VBATT 10F 2.5V TO 5.0V 0.1F SSM2301 VDD 1 0.01F OUT+ IN+ AUDIO IN+ GAIN FET MODULATOR CONTROL IN DRIVER OUT AUDIO IN 1 0.01F GAIN SD POP/CLICK BIAS OSCILLATOR SHUTDOWN SUPPRESSION GND NOTES 1 INPUT CAPS 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 2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. 06163-001SSM2301 TABLE OF CONTENTS Features .............................................................................................. 1 Typical Application Circuits ......................................................... 10 Applications....................................................................................... 1 Applications Information .............................................................. 12 General Description ......................................................................... 1 Overview ..................................................................................... 12 Functional Block Diagram .............................................................. 1 Gain Selection............................................................................. 12 Revision History ............................................................................... 2 Pop-and-Click Suppression ...................................................... 12 Specifications..................................................................................... 3 Layout .......................................................................................... 12 Absolute Maximum Ratings............................................................ 4 Input Capacitor Selection.......................................................... 12 Thermal Resistance ...................................................................... 4 Proper Power Supply Decoupling ............................................ 13 ESD Caution.................................................................................. 4 Outline Dimensions ....................................................................... 14 Pin Configurations and Function Descriptions ........................... 5 Ordering Guide .......................................................................... 14 Typical Performance Characteristics ............................................. 6 REVISION HISTORY 10/07Rev. 0 to Rev. A Added MSOP Package .......................................................Universal Changes to Features.......................................................................... 1 Changes to General Description .................................................... 1 Changes to Table 1............................................................................ 3 Deleted Evaluation Board Information Section ......................... 14 Updated Outline Dimensions ....................................................... 14 Changes to Ordering Guide .......................................................... 14 1/07Revision 0: Initial Version Rev. A Page 2 of 16