19-6278 Rev 0 5/12 EVALUATION KIT AVAILABLE MAX98355A/MAX98355B PCM Input Class D Audio Power Amplifiers General Description Features The MAX98355A/MAX98355B are digital pulse-code S Single-Supply Operation (2.5V to 5.5V) modulation (PCM) input Class D power amplifiers that S 3.2W Output Power into 4I at 5V provide Class AB audio performance with Class D effi- ciency. These ICs offer five selectable gain settings S 2.2mA Quiescent Current (3dB, 6dB, 9dB, 12dB, and 15dB) set by a single gain- S 92% Efficiency (R = 8I, P = 900mW, L OUT select input (GAIN). V = 3.7V) DD The digital audio interface is highly flexible with the 2 MAX98355A supporting I S data and the MAX98355B S 25V Output Noise (A = 15dB) RMS V supporting left-justified data. Both ICs support time divi- S Low 0.013% THD+N at 1kHz sion multiplexed (TDM) data. The digital audio interface accepts sample rates ranging from 8kHz to 96kHz for all S No MCLK Required supported data formats. The ICs can be configured to S Sample Rates of 8kHz to 96kHz produce a left channel, right channel, or (left + right)/2 S Supports Left, Right, or (Left + Right)/2 Outputs output from the stereo input data. The ICs operate using 2 16/24/32-bit data for I S and left justified modes as well S Sophisticated Edge Rate Control Enables as 16-bit data with up to four slots when using TDM Filterless Class D Outputs mode. The ICs eliminate the need for the external MCLK signal that is typically used for PCM communication. This S 77dB PSRR at 217Hz reduces EMI and possible board coupling issues in addi- S Low RF Susceptibility Rejects TDMA tion to reducing the size and pin count of the ICs. Noise from GSM Radios The ICs also feature a very high wideband jitter tolerance S Extensive Click-and-Pop Reduction Circuitry (12ns typ) on BCLK and LRCLK to provide robust operation. Active emissions-limiting, edge-rate limiting, and over- S Robust Short-Circuit and Thermal Protection shoot control circuitry greatly reduce EMI. A filterless S Available in Space-Saving Package: spread-spectrum modulation scheme eliminates the 1.345mm x 1.435mm WLP (0.4mm Pitch) need for output filtering found in traditional Class D devices and reduces the component count of the solution. The ICs are available in a 9-pin WLP package (1.345mm x 1.435mm x 0.64mm) and are specified over the -40NC Simplified Block Diagram to +85NC temperature range. Applications Cellular Phones SHUTDOWN Tablets AND GAIN MAX98355A CHANNEL Portable Media Players CONTROL MAX98355B SELECT Notebook Computers CLASS D DIGITAL PCM Ordering Information appears at end of data sheet. AUDIO DAC OUTPUT INPUT INTERFACE STAGE Functional Diagram appears at end of data sheet. For related parts and recommended products to use with this part, refer to www.maxim-ic.com/MAX98355A.related. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.MAX98355A/MAX98355B PCM Input Class D Audio Power Amplifiers TABLE OF CONTENTS General Description .................. 1 Applications .................... 1 Features ................... 1 Simplified Block Diagram .................. 1 Absolute Maximum Ratings ................ 4 Package Thermal Characteristics................ 4 Electrical Characteristics .................. 4 Typical Operating Characteristics ............... 9 General ....................................................................................9 Speaker Amplifier ............................................................................9 Pin Configuration ................... 16 Pin Description ................... 16 Detailed Description................... 17 Digital Audio Interface Modes.................................................................. 17 MCLK Elimination......................................................................... 17 Jitter Tolerance........................................................................... 17 BCLK Polarity............................................................................ 17 LRCLK Polarity........................................................................... 17 PCM Timing Characteristics................................................................. 18 Standby Mode ...........................................................................26 DAC Digital Filters ..........................................................................26 SD MODE and Shutdown Operation .............................................................26 Class D Speaker Amplifier ....................................................................27 Ultra-Low EMI Filterless Output Stage......................................................... 27 Speaker Current Limit .....................................................................28 Gain Selection ...........................................................................28 Click-and-Pop Suppression .................................................................28 Applications Information.................. 29 Filterless Class D Operation ................................................................... 31 Power-Supply Input .......................................................................... 31 Layout and Grounding ....................................................................... 31 WLP Applications Information .................................................................. 31 Functional Diagram ................. 32 Ordering Information .................. 32 Package Information................... 33 Revision History .................... 34 Maxim Integrated Products 2