EVALUATION KIT AVAILABLE MAX98371 Digital Input Class D Speaker Amplifier with Dynamic Headroom Tracking General Description Benefits and Features Wide Supply Range (5.5V to 18V) The MAX98371 is a high-efficiency, mono Class D audio amplifier featuring dynamic headroom tracking (DHT). Dynamic Headroom Tracking Maintains a Consistent Listening Experience DHT automatically optimizes the headroom available to the Class D amplifier as the power supply voltage var- Integrated Thermal Foldback Allows Robust ies, due to sudden transients and declining battery life to Operation in a WLP Package maintain a consistent listening experience. A wide 5.5V Remote Output Sensing Allows Up to 20dB THD+N to 18V supply range allows the device to reach 19W into Improvement When Ferrites Are Used an 8 load. Class D Edge Rate Control Enables Filterless Operation The MAX98371s flexible digital audio interface (DAI) 2 110dB A-Weighted Dynamic Range supports I S, left-justified, and TDM formats. The digital Output Power at 1% THD+N: audio interface accepts 32kHz, 44.1kHz, 48kHz, 88.2kHz, 15.7W into 8, V = 17V and 96kHz sample rates with 16-/24-/32-bit data sup- PVDD 13.2W into 4, V = 12V PVDD ported for all data formats. In TDM mode, the device can Output Power at 10% THD+N support up to 16 channels of audio data. A unique clock- 19W into 8, V = 17V ing structure eliminates the need for an external MCLK PVDD 15.8W into 4, V = 12V PVDD signal that is typically needed for PCM communication. Speaker Amplifier Efficiency This reduces pin count and simplifies board layout. 91% at 10W into 8, V = 12V PVDD Active emissions limiting with edge rate control minimizes 81% at 15W into 4, V = 12V PVDD EMI, and eliminates the need for output filtering found in Extensive Click-and-Pop Suppression traditional Class D devices. Space Saving, 30-Bump WLP Package (2.1mm x An 8-bit PVDD supply voltage ADC enables the Dynamic 2.6mm x 0.6mm, 0.4mm Pitch) Headroom Tracking circuit. DHT optimizes audio program peak behavior as the supply voltage varies and provides Simplified Block Diagram flexible user-defined parameters. Thermal foldback protection ensures robust behavior DVDD PVDD when the thermal limits of the device are exercised. The circuit can be enabled to automatically reduce the output power above a user specified temperature. This allows for MAX98371 uninterrupted music playback even at high ambient tem- peratures. Traditional thermal protection is also available THERMAL 2 DHT I C FOLDBACK in addition to robust overcurrent protection. All MAX98371 control is performed using a standard 2 2-wire, I C interface. One of sixteen slave addresses can D be selected through two, four-level address pins. The IC P V G CLASS D DAC O A is available in a 0.4mm pitch, 30-bump WLP package. It is L specified over the extended, -40C to +85C temperature range. Applications Ordering Information appears at end of data sheet. Tablets Notebook Computers Soundbars 19-7537 Rev 0 3/15 DIGITAL AUDIO INTERFACE DSPMAX98371 Digital Input Class D Speaker Amplifier with Dynamic Headroom Tracking TABLE OF CONTENTS General Description ............................................................................ 1 Applications .................................................................................. 1 Benefits and Features .......................................................................... 1 Simplified Block Diagram........................................................................ 1 Detailed Functional Diagram ..................................................................... 6 Absolute Maximum Ratings ...................................................................... 7 Package Thermal Characteristics ................................................................. 7 Electrical Characteristics ........................................................................ 7 2 I C Timing Characteristics ...................................................................... 14 Power Consumption ........................................................................... 15 Typical Operating Characteristics ................................................................ 16 Pin Configurations ............................................................................ 23 Pin Description ............................................................................... 24 Detailed Description........................................................................... 25 Interrupts 29 Status 29 State . 29 Flag . 29 Enable . 29 Clear . 29 Digital Audio Interface 40 Interface Format 41 Configuring the DAI Format . 41 Configuring the Digital Audio Input . 42 Digital Passband Filtering 47 Biquad Filter . 48 Signal Path Delay 48 PVDD ADC 49 Digital Volume Control . 49 Output Voltage Scaling 50 Dynamic Headroom Tracking 51 DHT Ballistics 58 Limiter 61 Maxim Integrated 2 www.maximintegrated.com