19-6044; Rev 0; 9/11 MAX97003 High-Efficiency, Low-Noise Audio Subsystem General Description Features The MAX97003 audio subsystem combines a mono speaker amplifier with a stereo headphone amplifier. The headphone and speaker amplifiers have independent volume and on/off controls. The four inputs are configurable as two differential or four single-ended inputs. S2.7V to 5.5V Speaker Supply Voltage S1.8V Headphone Supply Voltage S1.0W Speaker Output (VPVDD = 4.2V, ZSPK = 8I + 68µH, 1% THD+N) To minimize output noise, both the headphone and speaker outputs utilize a downward expander/noise gate to attenuate noise when no desired input signal is present. S32mW/Channel Headphone Output (RHP = 32I) The speaker output incorporates an adjustable dynamic range compressor (DRC) and distortion limiter to protect the speaker and maximize loudness. This allows high gain for low-level signals without compromising the quality of large signals. SEfficient Class H Headphone Amplifier All controls are performed using the two-wire I2C inter- SIntegrated Expander/Noise Gate for Low Output Noise SActive Emissions Limiting for Enhanced EMI Reduction SGround-Referenced Headphone Outputs SHeadphone Ground Sense S2 Stereo Single-Ended/Mono Differential Inputs face. The IC operates in the extended -40NC to +85NC temperature range, and is available in the 2.0mm x 2.4mm, 20-bump WLP package (0.4mm pitch). SIntegrated DRC (Speaker Outputs) SIntegrated Distortion Limiter (Speaker Outputs) Applications SExtensive Click-and-Pop Reduction Circuitry STDMA Noise Free Cell Phones S2.0mm x 2.4mm, 20-Bump WLP Package (0.4mm Pitch) Portable Media Players Ordering Information appears at end of data sheet. Simplified Block Diagram 1.8V I2C BATTERY POWER SUPPLY STEREO/ MONO INPUT CONTROL DRC AND EXPANDER VOLUME CLASS D AMPLIFIER LIMITER EXPANDER STEREO/ MONO INPUT VOLUME CLASS H AMPLIFIER CHARGE PUMP MAX97003 HEADPHONE GROUND SENSE For related parts and recommended products to use with this part, refer to: www.maxim-ic.com/MAX97003.related. ����������������������������������������������������������������� Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. MAX97003 High-Efficiency, Low-Noise Audio Subsystem TABLE OF CONTENTS General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Simplified Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Functional Diagram/Typical Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Digital I/O Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 I2C Timing Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Typical Operating Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Bump Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Bump Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Detailed Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Signal Path . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Class D Speaker Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Ultra-Low EMI Filterless Output Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Dynamic Range Compressor (DRC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Expander . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Speaker Low-Power Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Distortion Limiter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Headphone Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 DirectDrive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Charge Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Class H Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Ground Sense . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Volume-Change Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Zero-Crossing Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Volume Slewing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Enhanced Volume Smoothing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Volume Readback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 I2C Slave Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Registers Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Volume Readback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Input Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Mixers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Volume Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 ����������������������������������������������������������������� Maxim Integrated Products 2 MAX97003 High-Efficiency, Low-Noise Audio Subsystem TABLE OF CONTENTS (continued) Dynamic Range Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Expander (Noise Gate) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Distortion Limiter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Speaker Low-Power Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Output Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Advanced Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 Power Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 I2C Serial Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Bit Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 START and STOP Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Early STOP Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Slave Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Acknowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Write Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Read Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Applications Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Filterless Class D Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 RF Susceptibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Startup/Shutdown Sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Component Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Optional Ferrite Bead Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Input Capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Charge-Pump Capacitor Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Charge-Pump Flying Capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Charge-Pump Holding Capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Supply Bypassing, Layout, and Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 WLP Applications Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 ����������������������������������������������������������������� Maxim Integrated Products 3 MAX97003 High-Efficiency, Low-Noise Audio Subsystem LIST OF FIGURES Figure 1. Signal Path . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Figure 2. Stereo Single-Ended and Differential Input Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Figure 3. EMI with 12in of Speaker Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Figure 4. Low-Signal to High-Signal Transition, No Clipping, DRC Disabled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Figure 5. Low-Signal to High-Signal Transition, Increased Gain, DRC Disabled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Figure 6. Low-Signal to High-Signal Transition, Increased Gain, DRC Enabled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Figure 7. DRC Gain Curve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Figure 8. Expander Gain Curve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Figure 9. High-Signal to Low-Signal Transition, Expander Disabled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Figure 10. High-Signal to Low-Signal Transition, Expander Enabled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Figure 11. High-Signal to Low-Signal Transition, Speaker Expander with Speaker Low-Power Mode . . . . . . . . . . . . . 26 Figure 12. Limiter Gain Curve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Figure 13. Traditional Amplifier Output vs. MAX97003 DirectDrive Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Figure 14. Class H Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Figure 15. I2C Serial Interface Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Figure 16. START, STOP, and REPEATED START Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Figure 17. Acknowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Figure 18. Writing 1 Byte of Data to the IC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Figure 19. Writing n-Bytes of Data to the IC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Figure 20. Reading One Byte of Data from the IC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Figure 21. Reading n-Bytes of Data from the IC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Figure 22. Optional Class D Ferrite Bead Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Figure 23. WLP Ball Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 ����������������������������������������������������������������� Maxim Integrated Products 4 MAX97003 High-Efficiency, Low-Noise Audio Subsystem LIST OF TABLES Table 1. Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Table 2. Volume Readback Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Table 3. Input Configuration Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Table 4. Mixer Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Table 5. Headphone Volume Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Table 6. Dynamic Range Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Table 7. Expander Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Table 8. Distortion Limiter Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Table 9. Speaker Low-Power Mode Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Table 10. Output Gain Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Table 11. Advanced Configuration Control Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 Table 12. Power Management Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Table 13. Startup Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 ����������������������������������������������������������������� Maxim Integrated Products 5 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Functional Diagram/Typical Application Circuit 1.6V TO 2.0V 10µF 2.7V TO 5.5V 0.1µF 1µF VDD PVDD C3 1µF C1 PGAINA -3dB TO +12dB INA1 D4 BIAS HPLVOL: -63dB TO 0dB INADIFF 1µF INA2 D5 A5 HPL 0dB TO 6dB HPLEN HPLMIX PGAINA -3dB TO +12dB HPVSS EXPANDER + B4 HPSNS HPVDD MIX A4 HPR 0dB TO 6dB 1µF PGAINB -3dB TO +12dB INB1 C4 HPRVOL: -63dB TO 0dB HPRMIX INBDIFF PGAINB -3dB TO +12dB INB2 C5 HPREN HPVSS PVDD SPKVOL: -63dB TO 0dB D1 SPKP +12dB TO 24dB MIX 1µF D2 SPKN SPKEN SPKMIX PGND DRC AND EXPANDER + THD LIMITER THDCLP VDD VDD SDA C2 SCL B2 B5 BIAS HPVDD MIX 1µF 10µF MAX97003 CONTROL CHARGE PUMP B1 GND D3 PGND A2 A1 B3 A3 C1P C1N CPVDD CPVSS 1µF 1µF 1µF ����������������������������������������������������������������� Maxim Integrated Products 6 MAX97003 High-Efficiency, Low-Noise Audio Subsystem ABSOLUTE MAXIMUM RATINGS (Voltages with respect to GND.) VDD, CPVDD.........................................................-0.3V to +2.2V BIAS........................................................... -0.3V to (VDD + 0.3V) PVDD.....................................................................-0.3V to +6.0V PGND....................................................................-0.1V to +0.1V CPVSS.................................................................. -2.2V to +0.3V C1N.................................... (VCPVSS - 0.3V) to (VCPVDD + 0.3V) C1P...................................................... -0.3V to (VCPVDD + 0.3V) HPL, HPR........................... (VCPVSS - 0.3V) to (VCPVDD + 0.3V) INA1, INA2, INB1, INB2........................................-0.3V to +6.0V SDA, SCL..............................................................-0.3V to +6.0V SPKP, SPKN...........................................-0.3V to (VPVDD + 0.3V) HPSNS...................................................................-0.3V to +0.3V Continuous Current In/Out of PVDD, PGND, SPK_........ Q800mA Continuous Current In/Out of HPR, HPL, VDD............... Q140mA Continuous Input Current (all other pins)......................... Q20mA Duration of SPK_ Short Circuit to GND or PVDD.......Continuous Duration of Short Circuit Between SPKP and SPKN.... Continuous Duration of HP_ Short Circuit to GND or VDD............Continuous Continuous Power Dissipation (TA = +70NC) WLP Multilayer Board (derate 21.7mW/NC above +70NC).................................1.74W Junction Temperature......................................................+150NC Operating Temperature Range........................... -40NC to +85NC Storage Temperature Range............................. -65NC to +150NC Soldering Temperature (reflow).......................................+260NC Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. Headphone path: PGAIN_ = -1.5dB, HP_VOL = 0dB, HPGAIN = +2dB, input signal configured single-ended. Speaker path: PGAIN_ = 0dB, SPKVOL = 0dB, SPKGAIN = +12dB, input signal configured differential. Speaker loads (ZSPK) connected between SPKP and SPKN. Headphone loads (RHP) connected from HPL or HPR to GND. SDA and SCL pullup voltage = 1.8V. ZSPK = J, RHP = J. CC1P‑C1N = CCPVDD = CCPVSS = CBIAS = 1FF. TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 1) PARAMETER Speaker Amplifier Supply Voltage Range Headphone Amplifier Supply Voltage Range SYMBOL CONDITIONS TYP MAX UNITS PVDD Guaranteed by PSRR test 2.7 5.5 V VDD Guaranteed by PSRR test 1.6 2 V IVDD 1.21 1.6 IPVDD 1.07 1.3 IVDD 2.46 2.95 IPVDD 1.34 1.6 IVDD 0.1 0.15 IPVDD 2.25 2.6 IVDD 1.35 1.65 IPVDD 2.6 2.95 1.21 1.6 2.74 3.2 HP mode, TA = +25NC, stereo SE input on INA routed to HP output, HP expander disabled HP mode, TA = +25NC, stereo SE input on INA routed to HP output, HP expander enabled Quiescent Current MIN IDD SPK mode, TA = +25NC mono differential input on INA routed to SPK output; SPK expander, DRC, and limiter all disabled SPK mode, TA = +25NC mono differential input on INA routed to SPK output; SPK expander, DRC, and limiter all enabled SPK + HP mode, TA = +25NC IVDD stereo SE input on INA routed to HP and SPK output; SPK and HP expanders, DRC, and limiter IPVDD all disabled mA ����������������������������������������������������������������� Maxim Integrated Products 7 MAX97003 High-Efficiency, Low-Noise Audio Subsystem ELECTRICAL CHARACTERISTICS (continued) (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. Headphone path: PGAIN_ = -1.5dB, HP_VOL = 0dB, HPGAIN = +2dB, input signal configured single-ended. Speaker path: PGAIN_ = 0dB, SPKVOL = 0dB, SPKGAIN = +12dB, input signal configured differential. Speaker loads (ZSPK) connected between SPKP and SPKN. Headphone loads (RHP) connected from HPL or HPR to GND. SDA and SCL pullup voltage = 1.8V. ZSPK = J, RHP = J. CC1P‑C1N = CCPVDD = CCPVSS = CBIAS = 1FF. TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 1) PARAMETER Shutdown Current SYMBOL ISHDN Turn On-Time MIN TYP MAX IVDD, TA = +25NC CONDITIONS 0.08 2.5 IPVDD, TA = +25NC 0.05 1 SLEW = 0 17 SLEW = 1 10 -3dB to +9dB 15 20.4 28.5 +10.5dB to +12dB 5.2 6.96 9.5 -3.2 -2.98 -2.79 tON Time from power-on to full operation RIN TA = +25NC UNITS FA ms PREAMPLIFIERS Input Resistance PGAIN_ = 0x0 PGAIN_ = 0x1 -1.49 PGAIN_ = 0x2 Gain Maximum Input Signal Swing Common-Mode Rejection Ratio Input DC Voltage CMRR Bias Voltage VBIAS kI -0.22 -0.02 PGAIN_ = 0x3 1.57 PGAIN_ = 0x4 3.04 PGAIN_ = 0x5 4.52 PGAIN_ = 0x6 6.06 PGAIN_ = 0x7 7.51 PGAIN_ = 0x8 9.01 PGAIN_ = 0x9 10.59 +0.21 dB PGAIN_ = 0xA 11.82 12 12.36 Preamp = 0dB 2.4 VP-P 63 dB IN__ inputs 1.2 1.23 1.275 V 1.2 1.23 1.275 V TA = +25NC (volume at mute, SPKGAIN = 00) Q0.5 Q2.5 TA = +25NC (volume at 0dB, SPKGAIN = 00) Q1.0 -72 f = 1kHz (differential input mode), 0dB SPEAKER AMPLIFIER Output Offset Voltage Click-and-Pop Level VOS KCP Peak voltage, TA = +25NC, A-weighted, 32 samples per second, volume at 0dB, SPKGAIN = 00 (Note 2) Into shutdown mV dBV Out of shutdown -65 ����������������������������������������������������������������� Maxim Integrated Products 8 MAX97003 High-Efficiency, Low-Noise Audio Subsystem ELECTRICAL CHARACTERISTICS (continued) (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. Headphone path: PGAIN_ = -1.5dB, HP_VOL = 0dB, HPGAIN = +2dB, input signal configured single-ended. Speaker path: PGAIN_ = 0dB, SPKVOL = 0dB, SPKGAIN = +12dB, input signal configured differential. Speaker loads (ZSPK) connected between SPKP and SPKN. Headphone loads (RHP) connected from HPL or HPR to GND. SDA and SCL pullup voltage = 1.8V. ZSPK = J, RHP = J. CC1P‑C1N = CCPVDD = CCPVSS = CBIAS = 1FF. TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX 65 90.4 f = 217Hz, VRIPPLE = 200mVP-P 80 f = 1kHz, VRIPPLE = 200mVP-P 78 f = 10kHz, VRIPPLE = 200mVP-P 72 ZSPK = 8I + 68FH, VPVDD = 4.2V 1007 ZSPK = 8I + 68FH, VPVDD = 3.6V 735 ZSPK = 4I + 33FH, VPVDD = 5.0V 2585 VPVDD = 2.7V to 5.5V Power-Supply Rejection Ratio (Note 2) Output Power (Note 3) Total Harmonic Distortion Plus Noise Output Noise PSRR POUT THD+N TA = +25NC THD+N = 1% f = 1kHz, POUT = 700mW, TA = +25NC, ZSPK = 8I + 68FH dB 0.048 Noise gate disabled 40 Noise gate enabled 25 Noise gate disabled 93 Noise gate enabled 98 298.9 kHz Q10 kHz SNR A-weighted, POUT = 700mW Output Frequency fOSC Spread spectrum SPKGAIN = 00 Gain 0.06 0.029 Signal-to-Noise Ratio Spread-Spectrum Bandwidth mW % f = 1kHz, POUT = 350mW, TA = +25NC, ZSPK = 8I + 68FH A-weighted UNITS SPKGAIN = 01 FVRMS dB 11.69 15.4 15.65 SPKGAIN = 10 19.64 SPKGAIN = 11 23.7 15.92 dB Current Limit 2 A Efficiency h 92 % Volume Control POUT = 1W, f = 1kHz, ZSPK = 8I + 68FH SPKVOL = 0x00 -63.35 -62.87 -62.36 SPKVOL = 0x3F -0.044 0 0.13 Volume Control Step Size 1 dB Mute Attenuation f = 1kHz 118 dB dB ����������������������������������������������������������������� Maxim Integrated Products 9 MAX97003 High-Efficiency, Low-Noise Audio Subsystem ELECTRICAL CHARACTERISTICS (continued) (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. Headphone path: PGAIN_ = -1.5dB, HP_VOL = 0dB, HPGAIN = +2dB, input signal configured single-ended. Speaker path: PGAIN_ = 0dB, SPKVOL = 0dB, SPKGAIN = +12dB, input signal configured differential. Speaker loads (ZSPK) connected between SPKP and SPKN. Headphone loads (RHP) connected from HPL or HPR to GND. SDA and SCL pullup voltage = 1.8V. ZSPK = J, RHP = J. CC1P‑C1N = CCPVDD = CCPVSS = CBIAS = 1FF. TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX 80 83.3 86 665 500 UNITS CHARGE PUMP Charge-Pump Frequency Positive Output Voltage VCPVDD Negative Output Voltage VCPVSS Output Voltage Threshold VTH Mode Transition Timeouts VHPL = VHPR = 0V VHPL = VHPR = 0.2V kHz VHPL = VHPR = 0.5V VOUT > VTH VDD VOUT < VTH VDD/2 VOUT > VTH VOUT < VTH -VDD -VDD/2 QVDD x 0.216 QVDD x 0.25 QVDD x 0.278 V Time it takes for the charge pump to transition from invert to split mode 30 ms Time it takes for the charge pump to transition from split to invert mode 20 Fs Q0.15 Q0.5 mV -73 Output voltage at which the charge pump switches modes, VOUT rising or falling V V HEADPHONE AMPLIFIERS Output Offset Voltage Click-and-Pop Level Power-Supply Rejection Ratio (Note 2) VOS TA = +25NC KCP Peak voltage, TA = +25NC, A-weighted, 32 samples per second, volume at 0dB (Note 2) PSRR TA = +25NC Into shutdown dBV Out of shutdown -73 VDD = 1.6V to 2.0V 65 99.9 f = 217Hz, VRIPPLE = 200mVP-P 93 f = 1kHz, VRIPPLE = 200mVP-P 88 f = 20kHz, VRIPPLE = 200mVP-P 65 dB ���������������������������������������������������������������� Maxim Integrated Products 10 MAX97003 High-Efficiency, Low-Noise Audio Subsystem ELECTRICAL CHARACTERISTICS (continued) (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. Headphone path: PGAIN_ = -1.5dB, HP_VOL = 0dB, HPGAIN = +2dB, input signal configured single-ended. Speaker path: PGAIN_ = 0dB, SPKVOL = 0dB, SPKGAIN = +12dB, input signal configured differential. Speaker loads (ZSPK) connected between SPKP and SPKN. Headphone loads (RHP) connected from HPL or HPR to GND. SDA and SCL pullup voltage = 1.8V. ZSPK = J, RHP = J. CC1P‑C1N = CCPVDD = CCPVSS = CBIAS = 1FF. TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 1) PARAMETER Output Power SYMBOL POUT Channel-to-Channel Gain Tracking Total Harmonic Distortion Plus Noise Output Noise THD+N Signal-to-Noise Ratio Capacitive Drive SNR CL Crosstalk CONDITIONS THD+N = 1%, PGAINA = -1.5dB, HPGAIN = +2dB THD+N = 0.1%, PGAINA = -1.5dB, HPGAIN = +2dB MIN TYP MAX RHP = 16I 42 RHP = 32I 32 RHP = 32I 27 0.25 1.5 0.005 0.006 Noise gate disabled 10 Noise gate enabled 5.9 Noise gate disabled 94.2 Noise gate enabled 96.4 1000 -78 HPL to HPR, volume at 0dB, HPLMIX = 0x1, HPRMIX = 0x2, IN_DIFF = 0 RHP = 32I, POUT = 10mW, f = 1kHz RHP = 16I, POUT = 10mW, f = 1kHz A-weighted A-weighted, POUT = 10mW HPL to HPR, HPR to HPL, RHP = 32I, POUT = 10mW f = 20Hz to 10kHz Volume Control % % FVRMS dB pF -83 -0.53 -0.25 HPGAIN = 01 1.72 HPGAIN = 10 3.72 HPGAIN = 11 5.85 +0.09 dB HP_VOL = 0x00 -63.74 -63.3 -62.9 HP_VOL = 0x3F -0.50 -0.27 +0.09 1 dB 100 dB Volume Control Step Size Mute Attenuation mW dB f = 1kHz HPGAIN = 00 Gain UNITS f = 1kHz dB SPEAKER DRC Release Time Attack Time Compression Ratio DRCRLS = 000 800 DRCRLS = 101 25 DRCATK = 000 0.5 DRCATK = 111 50 DRCEN = 001 1.34:1 DRCEN = 101 J:1 ms/ step ms ratio ���������������������������������������������������������������� Maxim Integrated Products 11 MAX97003 High-Efficiency, Low-Noise Audio Subsystem ELECTRICAL CHARACTERISTICS (continued) (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. Headphone path: PGAIN_ = -1.5dB, HP_VOL = 0dB, HPGAIN = +2dB, input signal configured single-ended. Speaker path: PGAIN_ = 0dB, SPKVOL = 0dB, SPKGAIN = +12dB, input signal configured differential. Speaker loads (ZSPK) connected between SPKP and SPKN. Headphone loads (RHP) connected from HPL or HPR to GND. SDA and SCL pullup voltage = 1.8V. ZSPK = J, RHP = J. CC1P‑C1N = CCPVDD = CCPVSS = CBIAS = 1FF. TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 1) PARAMETER SYMBOL Compression Threshold CONDITIONS MIN TYP MAX DRCTH = 0x01 0.839 DRCTH = 0x1F 0.199 EXP_ATK = 000 500 EXP_ATK = 101 25 EXP_ATK = 110 15 Low-signal to high-signal transition 0.2 EXP_TH = 0x1 32 EXP_TH = 0xF 1 THDCLP = 0x1 <1 THDCLP = 0xF 24 UNITS VRMS SPEAKER AND HEADPHONE EXPANDER High signal to low signal transition Attack Time Release Time Expander Threshold ms/ step ms/ step mVP SPEAKER DISTORTION LIMITER Distortion Threshold Attack Time Release Time % 0.5 THDRLS = 000 0.076 THDRLS = 111 6.2 ms s DIGITAL I/O CHARACTERISTICS (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DIGITAL INPUTS (SDA and SCL) Input Voltage High ViH Input Voltage Low VIL Input Hysteresis 0.7 x VDD V 0.4 x VDD V VHYS 200 mV Input Capacitance CIN 10 pF Input Leakage Current IIN TA = +25NC Q1.0 FA Input Leakage Current IIN VDD = 0V, TA = +25NC Q1.0 FA 0.4 V DIGITAL OUTPUTS (SDA Open Drain) Output Low Voltage SDA VOL ISINK = 3mA ���������������������������������������������������������������� Maxim Integrated Products 12 MAX97003 High-Efficiency, Low-Noise Audio Subsystem I2C TIMING CHARACTERISTICS (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25NC.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 400 kHz Serial-Clock Frequency fSCL 0 Bus Free Time Between STOP and START Conditions tBUF 1.3 Fs Hold Time (Repeated) START Condition tHD,STA 0.6 Fs SCL Pulse-Width Low tLOW 1.3 Fs SCL Pulse-Width High tHIGH 0.6 Fs Setup Time for a Repeated START Condition tSU,STA 0.6 Fs Data Hold Time tHD,DAT 0 Data Setup Time tSU,DAT 100 ns ns 900 ns SDA and SCL Receiving Rise Time tR (Note 4) 20 + 0.1CB SDA and SCL Receiving Fall Time tF (Note 4) 20 + 0.1CB 300 ns SDA Transmitting Fall Time tF (Note 4) 20 + 0.1CB 250 ns 0.6 Setup Time for STOP Condition tSU,STO Bus Capacitance CB Pulse Width of Suppressed Spike tSP Note Note Note Note 0 Fs 400 pF 50 ns 1: 100% production tested at TA = +25NC. Specifications over temperature limits are guaranteed by design. 2: Amplifier inputs are AC-coupled to GND. 3: Class D amplifier testing performed with a resistive load in series with an inductor to simulate an actual speaker load. 4:CB is in pF. ���������������������������������������������������������������� Maxim Integrated Products 13 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Typical Operating Characteristics (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. Headphone path: PGAIN_ = -1.5dB, HP_VOL = 0dB, HPGAIN = +2dB, input signal configured singled-ended. Speaker path: PGAIN_ = 0dB, SPKVOL = 0dB, SPKGAIN = +12dB, input signal configured differential. Speaker loads (ZSPK) connected between SPKP and SPKN. Headphone loads (RHP) connected from HPL or HPR to GND. SDA and SCL pullup voltage = 1.8V. ZSPK = J, RHP = J. CC1P‑C1N = CCPVDD = CCPVSS = CBIAS = 1FF.) GENERAL SHUTDOWN CURRENT vs. SUPPLY VOLTAGE IPVDD SPK MODE EXPANDER, DRC, AND LIMITER DISABLED IPVDD 0.09 SHUTDOWN CURRENT (µA) SUPPLY CURRENT (mA) 2.5 0.10 MAX97003 toc01 3.0 2.0 1.5 1.0 MAX97003 toc02 SUPPLY CURRENT vs. SUPPLY VOLTAGE 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.5 0.01 0 0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 2.5 3.0 3.5 SUPPLY VOLTAGE (V) 4.0 4.5 5.0 5.5 SUPPLY VOLTAGE (V) SPEAKER AMPLIFIER 1 POUT = 800mW 0.01 1 POUT = 1.5W 0.1 0.01 0.001 1k FREQUENCY (Hz) 10 1 0.1 SSM 0.01 POUT = 200mW 100 VPVDD = 4.2V ZSPK = 8I + 68µH POUT = 600mW POUT = 500mW 0.001 10 100 10k 100k MAX97003 toc05 VPVDD = 4.2V ZSPK = 4I + 33µH 10 THD+N RATIO (%) THD+N RATIO (%) 10 TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY THD+N RATIO (%) VPVDD = 4.2V ZSPK = 8I + 68µH 0.1 100 MAX97003 toc03 100 TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY MAX97003 toc04 TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY FFM 0.001 10 100 1k FREQUENCY (Hz) 10k 100k 10 100 1k 10k 100k FREQUENCY (Hz) ���������������������������������������������������������������� Maxim Integrated Products 14 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Typical Operating Characteristics (continued) (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. Headphone path: PGAIN_ = -1.5dB, HP_VOL = 0dB, HPGAIN = +2dB, input signal configured singled-ended. Speaker path: PGAIN_ = 0dB, SPKVOL = 0dB, SPKGAIN = +12dB, input signal configured differential. Speaker loads (ZSPK) connected between SPKP and SPKN. Headphone loads (RHP) connected from HPL or HPR to GND. SDA and SCL pullup voltage = 1.8V. ZSPK = J, RHP = J. CC1P‑C1N = CCPVDD = CCPVSS = CBIAS = 1FF.) SPEAKER AMPLIFIER 0.1 f = 1kHz 0.01 f = 6kHz 0.1 f = 1kHz 0.01 f = 100kHz 0.001 1.0 1.5 2.0 f = 100kHz 0.001 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT POWER TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT POWER VPVDD = 3.6V ZSPK = 8I + 68µH f = 6kHz 0.1 f = 1kHz 0.01 f = 100kHz 0.001 1.0 1.5 2.0 OUTPUT POWER (W) 2.5 3.0 1 f = 6kHz 0.1 f = 1kHz 0.01 f = 100kHz 0.001 0.5 VPVDD = 3.6V ZSPK = 4I + 33µH 10 THD+N RATIO (%) THD+N RATIO (%) 10 1 100 MAX97003 toc10 100 1.6 MAX97003 toc11 TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT POWER f = 1kHz 0 f = 1kHz OUTPUT POWER (W) f = 6kHz 0.01 0.1 OUTPUT POWER (W) 10 0.1 f = 6kHz OUTPUT POWER (W) VPVDD = 4.2V ZSPK = 4I + 33µH 1 2.5 MAX97003 toc09 100 0.5 1 0.01 f = 100kHz 0.001 0 THD+N RATIO (%) 1 VPVDD = 4.2V ZSPK = 8I + 68µH 10 THD+N RATIO (%) f = 6kHz VPVDD = 5V ZSPK = 4I + 33µH 10 THD+N RATIO (%) THD+N RATIO (%) 10 100 MAX97003 toc07 VPVDD = 5V ZSPK = 8I + 68µH 1 100 MAX97003 toc06 100 TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT POWER MAX97003 toc08 TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT POWER TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT POWER f = 100kHz 0.001 0 0.2 0.4 0.6 0.8 OUTPUT POWER (W) 1.0 1.2 0 0.5 1.0 1.5 2.0 OUTPUT POWER (W) ���������������������������������������������������������������� Maxim Integrated Products 15 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Typical Operating Characteristics (continued) (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. Headphone path: PGAIN_ = -1.5dB, HP_VOL = 0dB, HPGAIN = +2dB, input signal configured singled-ended. Speaker path: PGAIN_ = 0dB, SPKVOL = 0dB, SPKGAIN = +12dB, input signal configured differential. Speaker loads (ZSPK) connected between SPKP and SPKN. Headphone loads (RHP) connected from HPL or HPR to GND. SDA and SCL pullup voltage = 1.8V. ZSPK = J, RHP = J. CC1P‑C1N = CCPVDD = CCPVSS = CBIAS = 1FF.) SPEAKER AMPLIFIER 60 50 40 60 50 40 30 20 20 VPVDD = 4.2V fIN = 1kHz 0 0 0.5 1.0 1.5 2.0 ZSPK = 8I + 68µH fIN = 1kHz 2.0 1.5 10% THD+N 1.0 1% THD+N 0.5 VPVDD = 3.6V fIN = 1kHz 10 0 2.5 MAX97003 toc14 ZSPK = 4I + 33µH 70 30 10 0 0.5 1.0 1.5 0 2.5 2.5 3.0 3.5 4.0 4.5 5.0 OUTPUT POWER (mW) OUTPUT POWER (mW) SUPPLY VOLTAGE (V) OUTPUT POWER vs. SUPPLY VOLTAGE OUTPUT POWER vs. LOAD RESISTANCE POWER-SUPPLY REJECTION RATIO vs. FREQUENCY 10% THD+N 2.0 1.5 1% THD+N 1.0 3.0 THD+N = 10% 2.0 1.5 2.5 3.0 3.5 4.0 4.5 SUPPLY VOLTAGE (V) 5.0 5.5 MAX97003 toc17 100 60 40 THD+N = 1% VPVDD = 4.2V VRIPPLE = 200mVP-P ZSPK = 8I + 68µH INPUTS AC-COUPLED TO GND 20 0.5 0 5.5 80 2.5 1.0 0.5 120 PSRR (dB) 3.0 2.5 3.5 OUTPUT POWER (W) 3.5 VPVDD = 4.2V ZSPK = LOAD + 68µH fIN = 1kHz MAX97003 toc16 ZSPK = 4I + 33µH fIN = 1kHz 4.0 4.0 MAX97003 toc15 4.5 OUTPUT POWER (W) 80 2.5 OUTPUT POWER (W) ZSPK = 4I + 33µH 70 ZSPK = 8I + 68µH 90 EFFICIENCY (%) EFFICIENCY (%) 80 100 MAX97003 toc12 90 OUTPUT POWER vs. SUPPLY VOLTAGE EFFICIENCY vs. OUTPUT POWER ZSPK = 8I + 68µH MAX97003 toc13 EFFICIENCY vs. OUTPUT POWER 100 0 0 1 10 100 LOAD RESISTANCE (I) 1k 10 100 1k 10k 100k FREQUENCY (Hz) ���������������������������������������������������������������� Maxim Integrated Products 16 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Typical Operating Characteristics (continued) (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. Headphone path: PGAIN_ = -1.5dB, HP_VOL = 0dB, HPGAIN = +2dB, input signal configured singled-ended. Speaker path: PGAIN_ = 0dB, SPKVOL = 0dB, SPKGAIN = +12dB, input signal configured differential. Speaker loads (ZSPK) connected between SPKP and SPKN. Headphone loads (RHP) connected from HPL or HPR to GND. SDA and SCL pullup voltage = 1.8V. ZSPK = J, RHP = J. CC1P‑C1N = CCPVDD = CCPVSS = CBIAS = 1FF.) SPEAKER AMPLIFIER 60 40 20 0 3.0 3.5 4.0 4.5 -80 -80 -100 -120 -120 -140 0 5k 10k 15k 20k 5k 0 10k 15k FREQUENCY (Hz) FREQUENCY (Hz) WIDEBAND OUTPUT SPECTRUM WIDEBAND OUTPUT SPECTRUM SPEAKER VOLUME GAIN vs. SPKVOL CODE -60 -80 -100 -20 -40 -60 -80 -100 -120 10 FREQUENCY (MHz) 100 0 -10 -20 -30 -40 -50 -60 -70 -120 1 20k MAX97003 toc23 RBW = 100Hz SSM SPEAKER VOLUME GAIN (dB) -40 0 MAX97003 toc22 RBW = 100Hz FFM 0.1 -60 -100 -140 5.5 MAX97003 toc21 OUTPUT AMPLITUDE (dBV) -60 -40 SUPPLY VOLTAGE (V) 0 -20 5.0 OUTPUT AMPLITUDE (dBV) 2.5 -40 FFM fIN = 1kHz -20 AMPLITUDE (dBV) AMPLITUDE (dBV) PSRR (dB) 80 SSM fIN = 1kHz -20 INBAND OUTPUT SPECTRUM 0 MAX97003 toc19 VRIPPLE = 200mVP-P fIN = 1kHz INPUTS AC-COUPLED TO GND 100 INBAND OUTPUT SPECTRUM 0 MAX97003 toc18 120 MAX97003 toc20 POWER-SUPPLY REJECTION RATIO vs. SUPPLY VOLTAGE 0.1 1 10 FREQUENCY (MHz) 100 0 10 20 30 40 50 60 70 SPKVOL CODE (NUMERIC) ���������������������������������������������������������������� Maxim Integrated Products 17 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Typical Operating Characteristics (continued) (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. Headphone path: PGAIN_ = -1.5dB, HP_VOL = 0dB, HPGAIN = +2dB, input signal configured singled-ended. Speaker path: PGAIN_ = 0dB, SPKVOL = 0dB, SPKGAIN = +12dB, input signal configured differential. Speaker loads (ZSPK) connected between SPKP and SPKN. Headphone loads (RHP) connected from HPL or HPR to GND. SDA and SCL pullup voltage = 1.8V. ZSPK = J, RHP = J. CC1P‑C1N = CCPVDD = CCPVSS = CBIAS = 1FF.) SPEAKER AMPLIFIER SHUTDOWN RESPONSE TURN-ON RESPONSE MAX97003 toc24 MAX97003 toc25 SCL 2V/div VS2EN = 0 SLEW = 0 ZCD = 0 SCL 2V/div VS2EN = 0 SLEW = 0 ZCD = 0 SPEAKER OUTPUT 200mA /div SPEAKER OUTPUT 200mA /div 2ms/div 4ms/div HEADPHONE AMPLIFIER 0.1 POUT = 5mW 0.01 10 100 1 0.1 1k FREQUENCY (Hz) 10k 10 1 0.1 f = 6kHz f = 1kHz 0.01 POUT = 25mW 0.001 100k RHP = 32I POUT = 10mW 0.01 POUT = 20mW 0.001 100 THD+N RATIO (%) THD+N RATIO (%) THD+N RATIO (%) 1 VPVDD = 4.2V VDD = 1.8V RHP = 16I 10 TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT POWER MAX97003 toc27 VPVDD = 4.2V VDD = 1.8V RHP = 32I 10 100 MAX97003 toc26 100 TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY MAX97003 toc28 TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY 10 100 1k FREQUENCY (Hz) 10k 100k f = 100Hz 0.001 0 0.010 0.020 0.030 0.040 0.050 0.005 0.015 0.025 0.035 0.045 OUTPUT POWER (W) ���������������������������������������������������������������� Maxim Integrated Products 18 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Typical Operating Characteristics (continued) (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. Headphone path: PGAIN_ = -1.5dB, HP_VOL = 0dB, HPGAIN = +2dB, input signal configured singled-ended. Speaker path: PGAIN_ = 0dB, SPKVOL = 0dB, SPKGAIN = +12dB, input signal configured differential. Speaker loads (ZSPK) connected between SPKP and SPKN. Headphone loads (RHP) connected from HPL or HPR to GND. SDA and SCL pullup voltage = 1.8V. ZSPK = J, RHP = J. CC1P‑C1N = CCPVDD = CCPVSS = CBIAS = 1FF.) HEADPHONE AMPLIFIER POWER DISSIPATION vs. OUTPUT POWER f = 6kHz f = 1kHz 0.01 0 0.01 0.02 RLOAD = 32I 50 40 30 0.04 0.05 0.06 0.07 20 40 60 80 100 120 OUTPUT POWER vs. LOAD RESISTANCE AND CHARGE-PUMP CAPACITANCE POWER-SUPPLY REJECTION RATIO vs. FREQUENCY 40 CCHARGE_PUMP = 1µF 30 CCHARGE_PUMP = 0.47µF 10 60 VPVDD = 4.2V VDD = 1.8V VRIPPLE = 200mVP-P on VDD INPUTS AC-COUPLED TO GND RLOAD = 32I 20 0 10 100 1k LOAD RESISTANCE (I) 10k 10k 0 fIN = 1kHz RLOAD = 32I -20 -40 -60 -80 -100 -120 -140 0 1 1k INBAND OUTPUT SPECTRUM 80 40 20 100 LOAD RESISTANCE (I) MAX97003 toc33 100 10 1 AMPLITUDE (dBV) 50 120 PSRR (dB) fIN = 1kHz THD+N = 1% CCHARGE_PUMP = CC1N-C1P CCPVDD = CCPVSS THD+N = 1% 30 140 160 OUTPUT POWER (mW) CCHARGE_PUMP = 2.2µF 40 0 0 OUTPUT POWER (W) 60 THD+N = 10% 50 10 0 0.03 60 20 fIN = 1kHz POUT = PHPL + PHPR 10 70 OUTPUT POWER (mW) 60 20 f = 100Hz 0.001 70 MAX97003 toc34 0.1 RLOAD = 16I 80 fIN = 1kHz 70 OUTPUT POWER (mW) 1 90 MAX97003 toc32 THD+N RATIO (%) 10 80 MAX97003 toc30 RHP = 16I OUTPUT POWER vs. LOAD RESISTANCE 100 POWER DISSIPATION (mW) MAX97003 toc29 100 MAX97003 toc31 TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT POWER -160 10 100 1k FREQUENCY (Hz) 10k 100k 0 2k 4k 6k 8k 10k 12k 14k 16k 18k 20k FREQUENCY (Hz) ���������������������������������������������������������������� Maxim Integrated Products 19 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Typical Operating Characteristics (continued) (VDD = 1.8V, VPVDD = 4.2V, VGND = VPGND = 0V. Headphone path: PGAIN_ = -1.5dB, HP_VOL = 0dB, HPGAIN = +2dB, input signal configured singled-ended. Speaker path: PGAIN_ = 0dB, SPKVOL = 0dB, SPKGAIN = +12dB, input signal configured differential. Speaker loads (ZSPK) connected between SPKP and SPKN. Headphone loads (RHP) connected from HPL or HPR to GND. SDA and SCL pullup voltage = 1.8V. ZSPK = J, RHP = J. CC1P‑C1N = CCPVDD = CCPVSS = CBIAS = 1FF.) HEADPHONE AMPLIFIER -20 CROSSTALK (dB) -60 -80 -100 80 -40 -60 HPR TO HPL -80 PGAIN = 0dB PGAIN = -3dB 60 PGAIN = 6dB 50 40 PGAIN = 12dB 30 HPL TO HPR -100 20 10 0 -120 -160 0 2k 4k 6k 8k 10k 12k 14k 16k 18k 20k 10 100 1k 10k FREQUENCY (Hz) FREQUENCY (Hz) HEADPHONE VOLUME GAIN vs. HP_VOL CODE SHUTDOWN RESPONSE 100k MAX97003 toc38 -10 10 100 1k 10k 100k FREQUENCY (Hz) MAX97003 toc39 0 HEADPHONE VOLUME GAIN (dB) RLOAD = 32I 90 70 -120 -140 100 MAX97003 toc36 RLOAD = 32I CMRR (dB) fIN = 1kHz RLOAD = 16I -40 AMPLITUDE (dBV) 0 MAX97003 toc35 0 -20 COMMON-MODE REJECTION RATIO vs. FREQUENCY CROSSTALK vs. FREQUENCY MAX97003 toc37 INBAND OUTPUT SPECTRUM TURN-ON RESPONSE MAX97003 toc40 SCL 2V/div SCL 2V/div VS2EN = 0 SLEW = 0 ZCD = 0 -20 -30 -40 HP_ 500mV/div -50 HP_ 500mV/div VS2EN = 0 SLEW = 0 ZCD = 0 -60 -70 0 10 20 30 40 50 60 70 4ms/div 4ms/div HP_VOL CODE (NUMERIC) ���������������������������������������������������������������� Maxim Integrated Products 20 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Bump Configuration TOP VIEW (BUMP SIDE DOWN) MAX97003 1 2 3 4 5 A C1N C1P CPVSS HPR HPL B GND SCL CPVDD HPSNS BIAS C PVDD SDA VDD INB1 INB2 D SPKP SPKN PGND INA1 INA2 + WLP Bump Description BUMP NAME FUNCTION A1 C1N Charge-Pump Flying Capacitor Negative Terminal. Connect a 1FF capacitor between C1P and C1N. A2 C1P Charge-Pump Flying Capacitor Positive Terminal. Connect a 1FF capacitor between C1P and C1N. A3 CPVSS A4 HPR Headphone Amplifier Right Output A5 HPL Headphone Amplifier Left Output B1 GND Analog Ground B2 SCL Serial Clock Input. Connect a pullup resistor from SCL to the I2C bus supply. B3 CPVDD Headphone Amplifier Positive Power Supply. Bypass with a 1FF capacitor to PGND. B4 HPSNS Headphone Ground Sense. Connect to the headset jack’s ground terminal. Headphone Amplifier Negative Power Supply. Bypass with a 1FF capacitor to PGND. B5 BIAS Common-Mode Bias. Bypass to GND with a 1FF capacitor. C1 PVDD Speaker Amplifier Power Supply. Bypass with a 0.1FF and a 10FF capacitor to PGND. C2 SDA Serial-Data Input/Output. Connect a pullup resistor from SDA to the I2C bus supply. C3 VDD Headphone Amplifier Supply. Bypass with a 0.1FF and a 10FF capacitor to GND. C4 INB1 Input B1. Left or negative input. C5 INB2 Input B2. Right or positive input. D1 SPKP Positive Speaker Output D2 SPKN Negative Speaker Output D3 PGND Speaker Amplifier Ground and Charge-Pump Ground D4 INA1 Input A1. Left or negative input. D5 INA2 Input A2. Right or positive input. ���������������������������������������������������������������� Maxim Integrated Products 21 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Detailed Description The MAX97003 audio subsystem combines a mono speaker amplifier with a stereo headphone amplifier. The high-efficiency 1W class D speaker amplifier operates directly from a lithium-ion battery and consumes no more than 0.05FA when in shutdown mode. The headphone amplifier utilizes a dual-mode charge pump and a Class H output stage to maximize efficiency while outputting a ground-referenced signal that does not require output coupling capacitors. The headphone and speaker amplifiers have independent volume and on/off control. The four inputs are configurable as two differential inputs or four single-ended inputs. All control is performed using the two-wire I2C interface. The speaker amplifier incorporates a distortion limiter to automatically reduce the volume level when excessive clipping occurs. This allows high gain for low-level signals without compromising the quality of large signals. The speaker amplifier also features an adjustable DRC that provides programmable compression or limiting of the audio signal. Both the headphone and speaker amplifiers feature a downward expander/noise gate to attenuate noise when no input signal is present. The headphone amplifier features a ground-sense pin to eliminate ground loop noise when the headphone jack is in use. Signal Path The signal path consists of flexible inputs, signal mixing, volume control, and output amplifiers (Figure 1). The inputs can be configured for single-ended or differential signals (Figure 2). The internal preamplifiers feature programmable gain settings using internal resistors. Following preamplification, the input signals are mixed, volume adjusted, and routed to the headphone and speaker amplifiers based on the desired configuration. Class D Speaker Amplifier The Class D speaker amplifier utilizes active emissionslimiting and spread-spectrum modulation to minimize the EMI radiated by the amplifier. HPL INA2 INA1 INPUT A -3dB TO +12dB -63dB TO 0dB 0dB TO +6dB MIXER AND MUX INB2 INB1 HPR -63dB TO 0dB 0dB TO +6dB SPKP INPUT B -3dB TO +12dB SPKN -63dB TO 0dB +12dB TO +24dB Figure 1. Signal Path ���������������������������������������������������������������� Maxim Integrated Products 22 MAX97003 High-Efficiency, Low-Noise Audio Subsystem STEREO SINGLE-ENDED IN_2 (R) R TO MIXER IN_1 (L) L DIFFERENTIAL IN_2 (+) IN_1 (-) TO MIXER Figure 2. Stereo Single-Ended and Differential Input Configurations EMISSION LEVEL (dBµV/m) 90 70 50 30 10 -10 0 100 200 300 400 500 600 700 800 900 1000 FREQUENCY (MHz) Ultra-Low EMI Filterless Output Stage Traditional Class D amplifiers require the use of external LC filters or shielding to meet EN55022B electromagnetic-interference (EMI) regulation standards. Maxim’s patented active emissions limiting edge-rate control circuitry and spread-spectrum modulation reduces EMI emissions, while maintaining up to 93% efficiency. Maxim’s spread-spectrum modulation mode flattens wideband spectral components, while proprietary techniques ensure that the cycle-to-cycle variation of the switching period does not degrade audio reproduction or efficiency. The IC’s spread-spectrum modulator randomly varies the switching frequency by Q10kHz around the center frequency (300kHz). Above 10MHz, the wideband spectrum looks like noise for EMI purposes. See Figure 3. Figure 3. EMI with 12in of Speaker Cable ���������������������������������������������������������������� Maxim Integrated Products 23 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Dynamic Range Compressor (DRC) The speaker amplifier features a dynamic range compressor (DRC) that attenuates high-amplitude signals and allows for a higher gain setting to be selected without clipping the output signal. This increases the perceived loudness of the audio signal and maintains a stable output amplitude despite changes in input amplitude. Figure 4, Figure 5, and Figure 6 demonstrate the benefits of using the DRC. Each of these figures uses the same input signal. Figure 4. Low-Signal to High-Signal Transition, No Clipping, DRC Disabled To operate the DRC, select a threshold level, compression ratio, attack time constant, and release time through registers 0x0A and 0x0B. When enabled, RMS signal levels that cross above the selected DRC threshold level are attenuated based on the selected compression ratio (Figure 7). Attenuation is achieved by automatically modifying the speaker volume to a lower gain setting. The user-selected gain setting is automatically restored when the RMS signal level falls below the DRC threshold. The attack time constant determines the time constant used when the DRC engages. The release time determines the time-per-step used when the DRC disengages. OUTPUT (VRMS) 0.85 1:1 1.5:1 2:1 Figure 5. Low-Signal to High-Signal Transition, Increased Gain, DRC Disabled 4:1 ∞:1 THRESHOLD 0.199 TO 0.839 Figure 6. Low-Signal to High-Signal Transition, Increased Gain, DRC Enabled 0.85 INPUT (VRMS) Figure 7. DRC Gain Curve ���������������������������������������������������������������� Maxim Integrated Products 24 MAX97003 High-Efficiency, Low-Noise Audio Subsystem OUTPUT (mVP) 1200 1:1 2:1 4:1 ∞:1 INPUT (mVP) Expander The IC’s speaker and headphone amplifier signal paths include and expander. The expander reduces the noise floor when there is no desired input signal by attenuating peak signals that are below the selected expander threshold (Figure 8). Attenuation is achieved by automatically modifying the speaker or headphone volume to a lower gain setting. Expansion ratio and attack time settings are configured by registers 0x0C for the headphone path and 0x0D for the speaker path. The expansion ratio determines the input:output relationship used when the input signal is below the selected threshold. The expansion attack time determines the time-per-step used when the expander engages. Figure 9 and Figure 10 show the benefits of the expander by comparing the output with the expander disabled against the output with the expander enabled. Figure 8. Expander Gain Curve The expander acts as a noise gate when the expansion ratio is set to an input:output relationship of infinity:1. In this case, all signals below the selected threshold are muted. Figure 9. High-Signal to Low-Signal Transition, Expander Disabled Figure 10. High-Signal to Low-Signal Transition, Expander Enabled THRESHOLD 1 TO 32 1200 ���������������������������������������������������������������� Maxim Integrated Products 25 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Speaker Low-Power Mode The IC’s speaker path expander includes a low-power mode that increases power efficiency when there is no desired input signal. Set the programmable threshold in register 0x0F to determine when low-power mode is activated. When low-power mode is enabled, the Class D switching output is active only if the speaker volume setting selected by the expander is above the selected low-power mode threshold. For example, if the speaker low-power mode threshold is set to -30dB and the input SPKP Distortion Limiter The speaker amplifier integrates a limiter to provide speaker protection and ensures high-quality audio. When enabled, the limiter monitors the audio signal at the output of the Class D speaker amplifier and decreases the gain if the distortion exceeds the predefined threshold. Attenuation is achieved by automatically modifying the speaker volume as appropriate. The limiter automatically tracks the battery voltage to reduce the gain as the battery voltage drops. Figure 12 shows the typical output vs. input curves with and without the distortion limiter. The dotted line shows the maximum gain for a given distortion limit without the distortion limiter. The solid line shows how, with the distortion limiter enabled, the gain can be increased without exceeding the set distortion limit. When the limiter is enabled, selecting a high gain level results in peak signals being attenuated while low signals are left unchanged. This increases the perceived loudness without the harshness of a clipped waveform. SPKN Figure 11. High-Signal to Low-Signal Transition, Speaker Expander with Speaker Low-Power Mode To operate the distortion limiter, select a distortion threshold and release time constant through the 0x0E register. ZCD must be set to 0 in register 0x11 for the distortion limiter to operate properly. DISTORTION (% THD+N) DISTORTION THRESHOLD LEVEL < 1 TO 24 signal is such that the speaker expander attenuates the output volume setting to at least -30dB, the Class D amplifier is turned off (Figure 11). Low-power mode is only available when the speaker expander is enabled. Headphone Amplifier DirectDrive Traditional single-supply headphone amplifiers have outputs biased at a nominal DC voltage (typically half the supply). Large coupling capacitors are needed to block this DC bias from the headphone. Without these capacitors, a significant amount of DC current flows to the headphone, resulting in unnecessary power dissipation and possible damage to both headphone and headphone amplifier. LIMITER ENABLED AND GAIN INCREASED LIMITER DISABLED INPUT Figure 12. Limiter Gain Curve Maxim’s patented DirectDriveM architecture uses a charge pump to create an internal negative supply voltage. This allows the headphone outputs of the IC to be biased at GND while operating from a single supply (Figure 13). Without a DC component, there is no need for the large DC-blocking capacitors. Instead of two large (220FF, typ) capacitors, the IC's charge pump requires DirectDrive is a registered trademark of Maxim Integrated Products, Inc. ���������������������������������������������������������������� Maxim Integrated Products 26 MAX97003 High-Efficiency, Low-Noise Audio Subsystem two small ceramic capacitors, conserving board space, reducing cost, and improving the frequency response of the headphone amplifier. See the Output Power vs. Charge-Pump Capacitance and Load Resistance graph in the Typical Operating Characteristics section for details of the possible capacitor sizes. There is a low DC voltage on the amplifier outputs due to amplifier offset. However, the offset of the IC is typically Q0.15mV, which, when combined with a 32I load, results in less than 5FA of DC current flow to the headphones. In addition to the cost and size disadvantages of the DC-blocking capacitors required by conventional headphone amplifiers, these capacitors limit the amplifier’s low-frequency response and can distort the audio signal. Previous attempts at eliminating the VDD VOUT VDD/2 GND CONVENTIONAL DRIVER-BIASING SCHEME +VDD VOUT VDD/2 -VDD DirectDrive BIASING SCHEME Figure 13. Traditional Amplifier Output vs. MAX97003 DirectDrive Output output-coupling capacitors involved biasing the headphone return (sleeve) to the DC bias voltage of the headphone amplifiers. This method raises a few issues: • The sleeve is typically grounded to the chassis. Using the midrail biasing approach, the sleeve must be isolated from system ground, complicating product design. • During an ESD strike, the amplifier’s ESD structures are the only path to system ground. Thus, the amplifier must be able to withstand the full energy from an ESD strike. • When using the headphone jack as a line out to other equipment, the bias voltage on the sleeve can conflict with the ground potential from other equipment, resulting in possible damage to the amplifiers. Charge Pump The IC’s dual-mode charge pump generates both the positive and negative power supply for the headphone amplifier. To maximize efficiency, both the charge pump’s switching frequency and output voltage change based on signal level. When the input signal level is less than 10% of VDD, the switching frequency is reduced to a low rate. This minimizes switching-losses in the charge pump. When the input signal exceeds 10% of VDD, the switching frequency increases to support the load current. For input signals below 25% of VDD, the charge pump generates Q(VDD/2) to minimize the voltage drop across the amplifier’s power stage and thus improves efficiency. Input signals that exceed 25% of VDD cause the charge pump to output QVDD. The higher output voltage allows for full output power from the headphone amplifier. To prevent audible glitches when transitioning from the Q(VDD/2) output mode to the QVDD output mode, the charge pump transitions very quickly. This quick change draws significant current from VDD for the duration of the transition. The bypass capacitor on VDD supplies the required current and prevent droop on VDD. The charge pump’s dynamic switching mode can be turned off through the I2C interface. The charge pump can then be forced to output either Q(VDD/2) or QVDD regardless of input signal level. ���������������������������������������������������������������� Maxim Integrated Products 27 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Class H Operation A Class H amplifier uses a Class AB output stage with power supplies that are modulated by the output signal. In the case of the IC, two nominal power-supply differentials of 1.8V (+0.9V to -0.9V) and 3.6V (+1.8V to -1.8V) are available from the charge pump. Figure 14 shows the operation of the output voltage dependent power supply. Ground Sense The headphone amplifier features output ground sensing that is used to reduce ground loop noise when the headphone output jack is connected to a different ground than the amplifier ground. An example of this is when the headphone jack is used as a lineout and connected to an external power amplifier. In addition, the ground sense reduces noise that can be caused by voltage drops between the amplifier ground and the headphone jack ground pin during normal headphone use. HPSNS must be connected to the ground pin on the headphone jack. Volume-Change Features The IC includes several features that enhance performance during volume changes. Zero-crossing detection, volume slewing, and enhanced volume smoothing are used to improve click-and-pop performance during volume changes. Volume readback is used to report the actual volume setting after the DRC, expander, or distortion limiter applies an automatic volume change. Zero-Crossing Detection The IC features zero-crossing detection to reduce clicks and pops during volume changes. When zero-crossing detection is enabled, all volume changes are delayed until a zero-crossing has been detected. If no zero-crossing is detected within 100ms, then the zero-crossing detector times out and volume changes are executed. 1.8V 0.9V VTH HPVDD 32ms OUTPUT VOLTAGE VTH -0.9V HPVSS -1.8V 32ms Disabling zero-crossing detection allows volume changes to occur immediately. Volume Slewing The IC offers volume slewing for all volume changes to further reduce clicks and pops. When enabled, the IC ramps through intermediate volume settings when a change to the volume is made. If zero-crossing detection is disabled, slewing occurs at a rate of 0.2ms per step. If zero-crossing detection is enabled, slew time depends on the input signal. If the duration between zero-crossings is less than 0.2ms, the slew time is limited at 0.2ms per volume change. If the duration between zero-crossings is longer than 0.2ms, volume changes occur at each zero-crossing. Volume slewing also provides a soft-start at power-on and soft-stop at power-off. Enhanced Volume Smoothing Enhanced volume smoothing can be used when the volume slewing feature is enabled. When enhanced volume smoothing is enabled and a volume change occurs, the IC waits for each step in the ramp to be applied before executing the next step. When zero-crossing detection is enabled, enhanced volume smoothing prevents large steps in the output volume when no zero-crossings are detected. Volume Readback The IC features three volume readback registers that report the actual volume settings of the speaker, left headphone, and right headphone volume registers. The DRC, expander, and distortion limiter are capable of automatically adjusting these volume registers according to their respective settings. I2C Slave Address The IC’s audio subsystem uses a slave address of 0x9A or 1001101 R/W. The address is defined as the 7 most significant bits (MSBs) followed by the read/write bit. Set the read/write bit to 1 to configure the audio subsystem to read mode. Set the read/write bit to 0 to configure the IC to write mode. The address is the first byte of information sent to the IC after the START condition. Registers Map 19 internal registers program the audio subsystem. Table 1 lists all of the registers, their addresses, and power-on-reset states. Register 0xFF indicates the device revision. Write zeros to all unused bits in the register table when updating the register, unless otherwise noted. Figure 14. Class H Operation ���������������������������������������������������������������� Maxim Integrated Products 28 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Table 1. Register Map REGISTER B7 B6 0 0 0 B5 B4 B3 B2 B1 B0 ADDRESS DEFAULT R/W HPLVOLRB 0x00 — R 0 HPRVOLRB 0x01 — R 0 0 SPKVOLRB 0x02 — R Input A Configuration 0 0 0 INADIFF PGAINA 0x03 0x00 R/W Input B Configuration 0 0 0 INBDIFF PGAINB 0x04 0x00 R/W HPRMIX 0x05 0x00 R/W 0 0 0 0 SPKMIX 0x06 0x00 R/W HPLM 0 HPLVOL 0x07 0x00 R/W HPRM 0 HPRVOL 0x08 0x00 R/W STATUS Left Headphone Volume Readback Right Headphone Volume Readback Speaker Volume Readback Headphone Mixer HPLMIX Speaker Mixer Left Headphone Volume Right Headphone Volume Speaker Volume SPKM Dynamic Range Control Dynamic Range Control 0 SPKVOL DRCEN 0 DRCATK 0 0x00 R/W 0x0A 0x00 R/W 0x0B 0x00 R/W Headphone Expander EXPHEN EXPHATK EXPHTH 0x0C 0x00 R/W Speaker Expander EXPSEN EXPSATK EXPSTH 0x0D 0x00 R/W THDRLS 0x0E 0x00 R/W 0x0F 0x00 R/W 0x10 0x00 R/W Distortion Limiter 0 0x09 DRCRLS DRCTH THDCLP Speaker Low-Power 0 SLPEN 0 0 0 0 0 Advanced Configuration VS2EN SLEW ZCD 0 FFM 0 CPSEL FIXED 0x11 0x00 R/W Power Management SHDN 0 0 0 0 SPKEN HPLEN HPREN 0x12 0x00 R/W 0xFF 0x40 R Mode Output Gain SLPTH HPGAIN SPKGAIN REVISION ID Rev ID REV ���������������������������������������������������������������� Maxim Integrated Products 29 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Volume Readback The Volume Readback registers report the actual volume setting of each output volume control when the DRC, expander, or distortion limiter is active. Table 2. Volume Readback Registers REGISTER BIT NAME DESCRIPTION Output Volume 5 4 0x00/0x01/ 0x02 3 2 1 0 HPLVOLRB/ HPRVOLRB/ SPKVOLRB VALUE GAIN (dB) VALUE GAIN (dB) VALUE GAIN (dB) VALUE GAIN (dB) 0x00 -63 0x10 -47 0x20 -31 0x30 -15 0x01 -62 0x11 -46 0x21 -30 0x31 -14 0x02 -61 0x12 -45 0x22 -29 0x32 -13 0x03 -60 0x13 -44 0x23 -28 0x33 -12 0x04 -59 0x14 -43 0x24 -27 0x34 -11 0x05 -58 0x15 -42 0x25 -26 0x35 -10 0x06 -57 0x16 -41 0x26 -25 0x36 -9 0x07 -56 0x17 -40 0x27 -24 0x37 -8 0x08 -55 0x18 -39 0x28 -23 0x38 -7 0x09 -54 0x19 -38 0x29 -22 0x39 -6 0x0A -53 0x1A -37 0x2A -21 0x3A -5 0x0B -52 0x1B -36 0x2B -20 0x3B -4 0x0C -51 0x1C -35 0x2C -19 0x3C -3 0x0D -50 0x1D -34 0x2D -18 0x3D -2 0x0E -49 0x1E -33 0x2E -17 0x3E -1 0x0F -48 0x1F -32 0x2F -16 0x3F 0 ���������������������������������������������������������������� Maxim Integrated Products 30 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Input Configuration The input configuration registers allow the selection of single-ended or differential modes as well as preamp gain settings for INA and INB. Table 3. Input Configuration Registers REGISTER BIT NAME 4 INADIFF/ INBDIFF DESCRIPTION Input A/B Differential Mode. Configures the input as either a mono differential signal (IN_ = IN_2 - IN_1) or as a stereo signal (IN_1 = left, IN_2 = right). 0 = Stereo single-ended 1 = Differential Input A/B Preamp Gain. Set the input gain to maximize output signal level for a given input signal range to improve the SNR of the system. 3 0x03/0x04 VALUE 2 1 0 PGAINA/ PGAINB LEVEL (dB) VALUE LEVEL (dB) 0x0 -3 0x6 +6 0x1 -1.5 0x7 +7.5 0x2 -0 0x8 +9 0x3 +1.5 0x9 +10.5 0x4 +3 0xA–0xF +12 0x5 +4.5 — — ���������������������������������������������������������������� Maxim Integrated Products 31 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Mixers The IC features independent mixers for the left headphone, right headphone, and speaker paths. Each output can select any combination of any inputs. This allows for mixing two audio signals together and routing independent signals to the headphone and speaker amplifiers. If one of the inputs is not selected by either mixer, it is automatically powered down to reduce current consumption. Table 4. Mixer Registers REGISTER BIT NAME 7 6 HPLMIX 5 4 0x05 HPRMIX 1 0 3 1 0 No input INA1 (Disabled when INADIFF = 1) INA2 (Select when INADIFF = 1) INB1 (Disabled when INBDIFF = 1) INB2 (Select when INBDIFF = 1) 0000 xxx1 xx1x x1xx 1xxx No input INA1 (Disabled when INADIFF = 1) INA2 (Select when INADIFF = 1) INB1 (Disabled when INBDIFF = 1) INB2 (Select when INBDIFF = 1) Speaker Mixer. Selects which of the four inputs is routed to the speaker output. 2 0x06 0000 xxx1 xx1x x1xx 1xxx Right Headphone Mixer. Selects which of the four inputs is routed to the right headphone output. 3 2 DESCRIPTION Left Headphone Mixer. Selects which of the four inputs is routed to the left headphone output. SPKMIX 0000 xxx1 xx1x x1xx 1xxx No input INA1 (Disabled when INADIFF = 1) INA2 (Select when INADIFF = 1) INB1 (Disabled when INBDIFF = 1) INB2 (Select when INBDIFF = 1) ���������������������������������������������������������������� Maxim Integrated Products 32 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Volume Control The speaker, left headphone, and right headphone have independent volume control registers that allow a gain to be selected from -63dB to 0dB. Table 5. Headphone Volume Control Registers REGISTER BIT NAME 7 HPLM/ HPRM/ SPKM DESCRIPTION Output Mute 0 = Unmuted 1 = Muted Output Volume 5 4 0x07/0x08/ 0x09 3 2 1 0 HPLVOL/ HPRVOL/ SPKVOL VALUE GAIN (dB) VALUE GAIN (dB) VALUE GAIN (dB) VALUE GAIN (dB) 0x00 -63 0x10 -47 0x20 -31 0x30 -15 0x01 -62 0x11 -46 0x21 -30 0x31 -14 0x02 -61 0x12 -45 0x22 -29 0x32 -13 0x03 -60 0x13 -44 0x23 -28 0x33 -12 0x04 -59 0x14 -43 0x24 -27 0x34 -11 0x05 -58 0x15 -42 0x25 -26 0x35 -10 0x06 -57 0x16 -41 0x26 -25 0x36 -9 0x07 -56 0x17 -40 0x27 -24 0x37 -8 0x08 -55 0x18 -39 0x28 -23 0x38 -7 0x09 -54 0x19 -38 0x29 -22 0x39 -6 0x0A -53 0x1A -37 0x2A -21 0x3A -5 0x0B -52 0x1B -36 0x2B -20 0x3B -4 0x0C -51 0x1C -35 0x2C -19 0x3C -3 0x0D -50 0x1D -34 0x2D -18 0x3D -2 0x0E -49 0x1E -33 0x2E -17 0x3E -1 0x0F -48 0x1F -32 0x2F -16 0x3F 0 ���������������������������������������������������������������� Maxim Integrated Products 33 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Dynamic Range Control The DRC attenuates high-level signals without affecting low-level signals. Attenuation is achieved by automatically modifying the speaker volume as appropriate. When the DRC is enabled, the overall volume can be increased without clipping the high-level signals. To operate the DRC, select a compression threshold, compression ratio, attack time constant, and release time. Table 6. Dynamic Range Control Registers REGISTER BIT NAME DRCEN DRC Enable and Compression Ratio 000 = 1:1 (disabled) 001 = 1.34:1 010 = 2:1 011 = 4:1 100 – 111 = J:1 DRCATK DRC Attack Time Constant. Defines the time constant used during attack. 00 = 500Fs 01 = 1ms 10 = 10ms 11 = 50ms DRCRLS 0 DRC Release Time. Defines the release rate per step. 000 = 800ms 001 = 400ms 010 = 150ms 011 = 75ms 100 = 50ms 101–111 = 25ms 4 Compression Threshold Level. Specifies the minimum input signal level for which compression is applied. 7 6 5 4 0x0A 3 2 1 3 0x0B DESCRIPTION 2 1 0 DRCTH VALUE LEVEL (VRMS) VALUE LEVEL (VRMS) 0x00 Reserved 0x10 0.354 0x01 0.839 0x11 0.334 0x02 0.792 0x12 0.315 0x03 0.748 0x13 0.298 0x04 0.706 0x14 0.281 0x05 0.667 0x15 0.265 0x06 0.629 0x16 0.251 0x07 0.594 0x17 0.237 0x08 0.561 0x18 0.223 0x09 0.529 0x19 0.211 0x0A 0.500 0x1A–0x1F 0.199 0x0B 0.472 0x0C 0.445 0x0D 0.421 0x0E 0.397 0x0F 0.375 ���������������������������������������������������������������� Maxim Integrated Products 34 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Expander (Noise Gate) The expander/noise gate eliminates noise when no desired signal is present by attenuating peak signals that are below the selected threshold. Attenuation is achieved by automatically modifying the headphone or speaker volume as appropriate. To operate the headphone or speaker expander, select an expansion threshold, expansion ratio, and attack time in the appropriate headphone or speaker expander registers. Table 7. Expander Registers REGISTER BIT NAME 7 EXPHEN/ EXPSEN 6 0x0C/0x0D EXPHATK/ EXPSATK 3 0 VALUE ATTACK TIME (ms/step) 000 001 010 011 100 101 110–111 500 350 250 100 50 25 15 Headphone/Speaker Noise Gate Threshold. The expander attenuates or mutes the output below this threshold. Thresholds are based on the PGA input signal level. 2 1 Headphone/Speaker Expansion Ratio 00 = 1:1 (disabled) 01 = 2:1 10 = 4:1 11 = J:1 (noise gate) Headphone/Speaker Expander Attack Time. Decreases volume after the signal drops below the selected expander threshold. 5 4 DESCRIPTION EXPHTH/ EXPSTH VALUE THRESHOLD (mVP) 0x0 0x1 0x2 0x3 0x4 0x5 0x6 0x7 Reserved 32 20 10 8 4 2 1 ���������������������������������������������������������������� Maxim Integrated Products 35 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Distortion Limiter The distortion limiter monitors the audio signal at the output of the Class D speaker amplifier and decreases the gain if the distortion exceeds the selected threshold. Attenuation is achieved by automatically modifying the speaker volume as appropriate. To operate the distortion limiter, select a distortion limit (% THD+N) and a release time constant. Table 8. Distortion Limiter Register REGISTER BIT NAME Distortion Limit. Measured in % THD+N. ZCD must be set to 0 for the distortion limiter to function. 7 6 THDCLP 5 0x0E 4 2 1 0 DESCRIPTION THDRLS VALUE DISTORTION LIMIT (%) VALUE DISTORTION LIMIT (%) 0x0 0x1 0x2 0x3 0x4 0x5 0x6 0x7 Limiter disabled <1 1 2 4 6 8 10 0x8 0x9 0xA 0xB 0xC 0xD 0xE 0xF 12 14 16 18 20 21 22 24 Limiter Release Time Constant. Time constant used while increasing the gain after distortion is no longer detected at the output. 000 = 6.2s 001 = 3.1s 010 = 1.6s 011 = 815ms 100 = 419ms 101 = 223ms 110 = 116ms 111 = 76ms ���������������������������������������������������������������� Maxim Integrated Products 36 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Speaker Low-Power Mode The speaker expander includes a low-power mode that increases power efficiency when a desired audio signal is not present. When this feature is enabled, the Class D switching output is active only if the speaker volume setting selected by the expander is above the selected low-power mode threshold. Low-power mode is only available when the speaker expander is enabled. Table 9. Speaker Low-Power Mode Register REGISTER BIT 7 NAME SLPEN 4 3 0x0F 1 0 Speaker Low-Power Mode. Only functions if EXPSEN ≠ 0. 0 = Class D output is active continuously. 1 = Class D output is active if the speaker volume setting selected by the expander is above SLPTH. Speaker Low-Power Mode Volume Threshold. Threshold used to determine if speaker amplifier should be enabled or disabled. If the volume selected by the expander is less than this threshold, the speaker amplifier is disabled. 5 2 DESCRIPTION SLPTH VALUE GAIN (dB) VALUE GAIN (dB) VALUE GAIN (dB) VALUE GAIN (dB) 0x00 -63 0x10 -47 0x20 -31 0x30 -15 0x01 -62 0x11 -46 0x21 -30 0x31 -14 0x02 -61 0x12 -45 0x22 -29 0x32 -13 0x03 -60 0x13 -44 0x23 -28 0x33 -12 0x04 -59 0x14 -43 0x24 -27 0x34 -11 0x05 -58 0x15 -42 0x25 -26 0x35 -10 0x06 -57 0x16 -41 0x26 -25 0x36 -9 0x07 -56 0x17 -40 0x27 -24 0x37 -8 0x08 -55 0x18 -39 0x28 -23 0x38 -7 0x09 -54 0x19 -38 0x29 -22 0x39 -6 0x0A -53 0x1A -37 0x2A -21 0x3A -5 0x0B -52 0x1B -36 0x2B -20 0x3B -4 0x0C -51 0x1C -35 0x2C -19 0x3C -3 0x0D -50 0x1D -34 0x2D -18 0x3D -2 0x0E -49 0x1E -33 0x2E -17 0x3E -1 0x0F -48 0x1F -32 0x2F -16 0x3F 0 ���������������������������������������������������������������� Maxim Integrated Products 37 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Output Gain The output stage of the headphone and speaker amplifiers can be configured to provide additional gain. The headphone amplifier allows a range of 0dB to +6dB. The speaker amplifier allows range of +12dB to +24dB. Table 10. Output Gain Register REGISTER BIT NAME DESCRIPTION HPGAIN Headphone Output Gain 00 = 0dB 01 = +2dB 10 = +4dB 11 = +6dB SPKGAIN Speaker Output Gain 00 = +12dB 01 = +16dB 10 = +20dB 11 = +24dB 3 2 0x10 1 0 ���������������������������������������������������������������� Maxim Integrated Products 38 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Advanced Configuration The IC includes several advanced configurations related to automatic volume changes initiated by the DRC, expander, and distortion limiter. In addition, settings for the Class D speaker modulation scheme and headphone charge pump are configured in register 0x11. Table 11. Advanced Configuration Register REGISTER BIT 7 6 0x11 NAME DESCRIPTION VS2EN Enhanced Volume Smoothing. During volume slewing, the controller waits for each step in the ramp to be applied before executing the next step. When zero-crossing detection is enabled, this prevents large steps in the output volume when no zero-crossings are detected. 0 = Disabled 1 = Enabled SLEW Volume Slewing. Determines whether volume slewing is used on all volume control changes to reduce clicks and pops. When enabled, volume changes cause the IC to ramp through intermediate volume settings whenever a change to the volume is made. If ZCD = 1, slewing occurs at a rate of 0.2ms per step. If ZCD = 0, slew time depends on the input signal frequency. This bit also activates soft-start at power-on and soft-stop at power-off. 0 = Enabled 1 = Disabled 5 ZCD Zero-Crossing Detection. Determines whether zero-crossing detection is used on all volume control changes to reduce clicks and pops. Disabling zero-crossing detection allows volume changes to occur immediately. Zero-crossing detection times out at 100ms. 0 = Enabled 1 = Disabled 3 FFM Fixed Class D Frequency Enable 0 = Spread-spectrum modulation 1 = Fixed-frequency modulation 1 0 CPSEL Charge-Pump Output Select. Works with FIXED to set QVDD or QVDD/2 outputs on CPVDD and CPVSS. Ignored when FIXED = 0. 0 = QVDD on CPVDD/CPVSS 1 = QVDD/2 on CPVDD/CPVSS FIXED Class H Mode. When enabled, this bit forces the charge pump to generate static power rails for CPVDD and CPVSS, instead of dynamically adjusting them based on output signal level. 0 = Class H mode 1 = Fixed supply mode ���������������������������������������������������������������� Maxim Integrated Products 39 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Power Management The power management register allows the speaker, left headphone, and right headphone signal paths to be enabled. It also enables the IC device. Table 12. Power Management Register REGISTER BIT NAME DESCRIPTION 7 SHDN Software Shutdown 0 = Device disabled 1 = Device enabled 2 SPKEN Speaker Amplifier Enable 0 = Disabled 1 = Enabled 1 HPLEN Left Headphone Amplifier Enable 0 = Disabled 1 = Enabled 0 HPREN Right Headphone Amplifier Enable 0 = Disabled 1 = Enabled 0x12 I2C Serial Interface The IC features an I2C/SMBus-compatible, two-wire serial interface consisting of a serial-data line (SDA) and a serial-clock line (SCL). SDA and SCL facilitate communication between the IC and the master at clock rates up to 400kHz. Figure 1 shows the two-wire interface timing diagram. The master generates SCL and initiates data transfer on the bus. The master device writes data to the IC by transmitting the proper slave address followed by the register address and then the data word. Each transmit sequence is framed by a START (S) or REPEATED START (Sr) condition and a STOP (P) condition. Each word transmitted to the IC is 8 bits long and is followed by an acknowledge clock pulse. A master reading data from the IC transmits the proper slave address followed by a series of nine SCL pulses. The IC transmits data on SDA in sync with the master-generated SCL pulses. The master acknowledges receipt of each byte of data. Each read sequence is framed by a START (S) or REPEATED START (Sr) condition, a not acknowledge, and a STOP SDA tSU,STA tSU,DAT tLOW tBUF tHD,STA tHD,DAT tSP tSU,STO tHIGH SCL tHD,STA tR tF START CONDITION REPEATED START CONDITION STOP CONDITION START CONDITION Figure 15. I2C Serial Interface Timing Diagram ���������������������������������������������������������������� Maxim Integrated Products 40 MAX97003 High-Efficiency, Low-Noise Audio Subsystem (P) condition. SDA operates as both an input and an open-drain output. A pullup resistor, typically greater than 500I, is required on SDA. SCL operates only as an input. A pullup resistor, typically greater than 500I, is required on SCL if there are multiple masters on the bus, or if the single master has an open-drain SCL output. Series resistors in line with SDA and SCL are optional. Series resistors protect the digital inputs of the IC from high voltage spikes on the bus lines, and minimize crosstalk and undershoot of the bus signals. Bit Transfer One data bit is transferred during each SCL cycle. The data on SDA must remain stable during the high period of the SCL pulse. Changes in SDA while SCL is high are control signals. See the START and STOP Conditions section. START and STOP Conditions SDA and SCL idle high when the bus is not in use. A master initiates communication by issuing a START condition. A START condition is a high-to-low transition on SDA with SCL high. A STOP condition is a low-to-high transition on SDA while SCL is high (Figure 16). A START condition from the master signals the beginning of a transmission to the IC. The master terminates transmission, and frees S Sr P SCL SDA Figure 16. START, STOP, and REPEATED START Conditions Early STOP Conditions The IC recognizes a STOP condition at any point during data transmission except if the STOP condition occurs in the same high pulse as a START condition. For proper operation, do not send a STOP condition during the same SCL high pulse as the START condition. Slave Address The slave address is defined as the seven most significant bits (MSBs) followed by the read/write bit. For the IC, the seven most significant bits are 1001101. Setting the read/write bit to 1 (slave address = 0x9B) configures the IC for read mode. Setting the read/write bit to 0 (slave address = 0x9A) configures the IC for write mode. The address is the first byte of information sent to the IC after the START condition. Acknowledge The acknowledge bit (ACK) is a clocked ninth bit that the IC uses to handshake receipt each byte of data when in write mode (Figure 17). The IC pulls down SDA during the entire master-generated ninth clock pulse if the previous byte is successfully received. Monitoring ACK allows for detection of unsuccessful data transfers. An unsuccessful data transfer occurs if a receiving device is busy or if a system fault has occurred. In the event of an unsuccessful data transfer, the bus master retries communication. The master pulls down SDA during the ninth clock cycle to acknowledge receipt of data when the IC is in read mode. An acknowledge is sent by the master after each read byte to allow data transfer to continue. A not-acknowledge is sent when the master reads the final byte of data from the IC, followed by a STOP condition. CLOCK PULSE FOR ACKNOWLEDGMENT START CONDITION SCL the bus, by issuing a STOP condition. The bus remains active if a REPEATED START condition is generated instead of a STOP condition. 1 28 9 NOT ACKNOWLEDGE SDA ACKNOWLEDGE Figure 17. Acknowledge ���������������������������������������������������������������� Maxim Integrated Products 41 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Write Data Format A write to the IC includes transmission of a START condition, the slave address with the R/W bit set to 0, one byte of data to configure the internal register address pointer, one or more bytes of data, and a STOP condition. Figure 18 illustrates the proper frame format for writing one byte of data to the IC. Figure 19 illustrates the frame format for writing n-bytes of data to the IC. The slave address with the R/W bit set to 0 indicates that the master intends to write data to the IC. The IC acknowledges receipt of the address byte during the master-generated ninth SCL pulse. The second byte transmitted from the master configures the IC’s internal register address pointer. The pointer tells the IC where to write the next byte of data. An acknowledge pulse is sent by the IC upon receipt of the address pointer data. The third byte sent to the IC contains the data that are written to the chosen register. An acknowledge pulse from the IC signals receipt of the data byte. The address pointer autoincrements to the next register address after each received data byte. This autoincrement feature allows a master to write to sequential registers within one continuous frame. The master signals the end of transmission by issuing a STOP condition. Register addresses greater than 0x12 are reserved. Do not write to these addresses. ACKNOWLEDGE FROM SLAVE B7 ACKNOWLEDGE FROM SLAVE SLAVE ADDRESS S 0 B6 B5 B4 B3 B2 B1 B0 ACKNOWLEDGE FROM SLAVE A REGISTER ADDRESS A A DATA BYTE R/W P 1 BYTE AUTOINCREMENT INTERNAL REGISTER ADDRESS POINTER Figure 18. Writing 1 Byte of Data to the IC ACKNOWLEDGE FROM SLAVE S SLAVE ADDRESS ACKNOWLEDGE FROM SLAVE 0 A REGISTER ADDRESS R/W A ACKNOWLEDGE FROM SLAVE ACKNOWLEDGE FROM SLAVE B7 B6 B5 B4 B3 B2 B1 B0 B7 B6 B5 B4 B3 B2 B1 B0 DATA BYTE 1 A 1 BYTE DATA BYTE n A P 1 BYTE AUTOINCREMENT INTERNAL REGISTER ADDRESS POINTER Figure 19. Writing n-Bytes of Data to the IC ���������������������������������������������������������������� Maxim Integrated Products 42 MAX97003 High-Efficiency, Low-Noise Audio Subsystem The address pointer can be preset to a specific register before a read command is issued. The master presets the address pointer by first sending the IC’s slave address with the R/W bit set to 0 followed by the register address. A REPEATED START condition is then sent followed by the slave address with the R/W bit set to 1. The IC then transmits the contents of the specified register. The address pointer autoincrements after transmitting the first byte. Read Data Format Send the slave address with the R/W bit set to 1 to initiate a read operation. The IC acknowledges receipt of its slave address by pulling SDA low during the ninth SCL clock pulse. A START command followed by a read command resets the address pointer to register 0x00. The first byte transmitted from the IC is the contents of register 0x00. Transmitted data is valid on the rising edge of SCL. The address pointer autoincrements after each read data byte. This autoincrement feature allows all registers to be read sequentially within one continuous frame. A STOP condition can be issued after any number of read data bytes. If a STOP condition is issued followed by another read operation, the first data byte to be read are from register 0x00. ACKNOWLEDGE FROM SLAVE S SLAVE ADDRESS The master acknowledges receipt of each read byte during the acknowledge clock pulse. The master must acknowledge all correctly received bytes except the last byte. The final byte must be followed by a not acknowledge from the master and then a STOP condition. Figure 20 illustrates the frame format for reading one byte from the IC. Figure 21 illustrates the frame format for reading multiple bytes from the IC. ACKNOWLEDGE FROM SLAVE A 0 REGISTER ADDRESS R/W NOT ACKNOWLEDGE FROM MASTER ACKNOWLEDGE FROM SLAVE Sr A SLAVE ADDRESS REPEATED START 1 A R/W DATA BYTE A P 1 BYTE AUTOINCREMENT INTERNAL REGISTER ADDRESS POINTER Figure 20. Reading One Byte of Data from the IC ACKNOWLEDGE FROM SALVE ACKNOWLEDGE FROM SLAVE S SLAVE ADDRESS 0 A REGISTER ADDRESS R/W ACKNOWLEDGE FROM SLAVE A REPEATED START Sr SLAVE ADDRESS 1 R/W A DATA BYTE A 1 BYTE AUTOINCREMENT INTERNAL REGISTER ADDRESS POINTER Figure 21. Reading n-Bytes of Data from the IC ���������������������������������������������������������������� Maxim Integrated Products 43 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Applications Information Filterless Class D Operation Traditional Class D amplifiers require an output filter to recover the audio signal from the amplifier’s output. The filters add cost, increase the solution size of the amplifier, and can decrease efficiency and THD+N performance. The traditional PWM scheme uses large differential output swings (2 x VPVDD peak-to-peak) and causes large ripple currents. Any parasitic resistance in the filter components results in a loss of power, lowering the efficiency. The IC does not require an output filter. The device relies on the inherent inductance of the speaker coil and the natural filtering of both the speaker and the human ear to recover the audio component of the square-wave output. Eliminating the output filter results in a smaller, less costly, more efficient solution. Because the frequency of the IC output is well beyond the bandwidth of most speakers, voice coil movement due to the square-wave frequency is very small. Although this movement is small, a speaker not designed to handle the additional power can be damaged. For optimum results, use a speaker with a series inductance > 10FH. Typical 8I speakers exhibit series inductances in the 20FH to 100FH range. RF Susceptibility GSM radios transmit using time-division multiple access (TDMA) with 217Hz intervals. The result is an RF signal with strong amplitude modulation at 217Hz and its harmonics that is easily demodulated by audio amplifiers. The IC is designed specifically to reject RF signals. PCB layout, however, has a large impact on the susceptibility of the end product. In RF applications, improvements to both layout and component selection decreases the IC’s susceptibility to RF noise and prevent RF signals from being demodulated into audible noise. Trace lengths should be kept below 1/4 of the wavelength of the RF frequency of interest. Minimizing the trace lengths prevents them from functioning as antennas and coupling RF signals into the IC. The wavelength (l) in meters is given by: l = c/f where c = 3 x 108 m/s, and f = the RF frequency of interest. Route audio signals on middle layers of the PCB to allow ground planes above and below to shield them from RF interference. Ideally, the top and bottom layers of the PCB should primarily be ground planes to create effective shielding. Additional RF immunity can also be obtained by relying on the self-resonant frequency of capacitors as it exhibits the frequency response similar to a notch filter. Depending on the manufacturer, 10pF to 20pF capacitors typically exhibit self resonance at RF frequencies. These capacitors when placed at the input pins can effectively shunt the RF noise at the inputs of the IC. For these capacitors to be effective, they must have a lowimpedance, low-inductance path to the ground plane. Avoid using microvias to connect to the ground plane whenever possible as these vias do not conduct well at RF frequencies. Startup/Shutdown Sequencing To ensure proper device initialization and minimal clickand-pop, program the IC’s control registers in the correct order. Table 13 lists the correct startup sequence for the device. To shutdown the IC, simply set SHDN = 0. Table 13. Startup Sequence SEQUENCE DESCRIPTION REGISTERS 1 Ensure SHDN = 0 0x12 2 Configure inputs 0x03, 0x04 3 Configure mixers 0x05, 0x06 4 Configure volume 0x07, 0x08, 0x09 5 Configure output gain 0x10 6 Enable amplifiers 0x12 7 Configure expander and DRC 0x0A–0x0F 10 Set SHDN = 1 0x12 ���������������������������������������������������������������� Maxim Integrated Products 44 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Component Selection Optional Ferrite Bead Filter For applications in which speaker leads exceed 20mm, additional EMI suppression can be achieved by using a filter constructed from a ferrite bead and a capacitor to ground (Figure 22). Use a ferrite bead with low DC resistance, high frequency (> 600MHz) impedance between 100I and 600I, and rated for at least 1A. The capacitor value varies based on the ferrite bead chosen and the actual speaker lead length. Select a capacitor less than 1nF based on EMI performance. Input Capacitor An input capacitor, CIN, in conjunction with the input impedance of the IC line inputs forms a highpass filter that removes the DC bias from an incoming analog signal. The AC-coupling capacitor allows the amplifier to automatically bias the signal to an optimum DC level. Assuming zero source impedance, the -3dB point of the highpass filter is given by: f-3dB = 1 2πRINCIN RIN is defined in the Electrical Characteristics table under the Input Resistance section. Choose CIN so that f-3dB is well below the lowest frequency of interest. For best audio quality, use capacitors whose dielectrics have low-voltage coefficients, such as tantalum or aluminum electrolytic. Capacitors with high-voltage coefficients, such as ceramics, can result in increased distortion at low frequencies. Charge-Pump Capacitor Selection Use capacitors with an ESR less than 100mI for optimum performance. Low-ESR ceramic capacitors minimize the output resistance of the charge pump. Most surfacemount ceramic capacitors satisfy the ESR requirement. For best performance over the extended temperature range, select capacitors with an X7R dielectric. SPKP MAX97000 CLASS D SPKN Figure 22. Optional Class D Ferrite Bead Filter Charge-Pump Flying Capacitor The value of the flying capacitor (connected between C1N and C1P) affects the output resistance of the charge pump. A value that is too small degrades the device’s ability to provide sufficient current drive, which leads to a loss of output voltage. Increasing the value of the flying capacitor reduces the charge-pump output resistance to an extent. Above 1FF, the on-resistance of the internal switches and the ESR of external charge-pump capacitors dominate. Charge-Pump Holding Capacitor The holding capacitor (bypassing CPVSS) value and ESR directly affect the ripple at CPVSS. Increasing the capacitor’s value reduces output ripple. Likewise, decreasing the ESR reduces both ripple and output resistance. Lower capacitance values can be used in systems with low maximum output power levels. See the Output Power vs. Load Resistance graph in the Typical Operating Characteristics section for more information. Supply Bypassing, Layout, and Grounding Proper layout and grounding are essential for optimum performance. Use a large continuous ground plane on a dedicated layer of the PCB to minimize loop areas. Connect GND and PGND directly to the ground plane using the shortest trace length possible. Proper grounding improves audio performance, minimizes crosstalk between channels, and prevents digital noise from coupling into the analog signals. Place the capacitor between C1P and C1N as close as possible to the IC to minimize trace length from C1P to C1N. Inductance and resistance added to C1P and C1N reduce the output power of the headphone amplifier. Bypass CPVDD and CPVSS with capacitors located close to the pins with a short trace length to PGND. Close decoupling of CPVDD and CPVSS minimizes supply ripple and maximizes output power from the headphone amplifier. Bypass PVDD to PGND with as little trace length as possible. Connect SPKP and SPKN to the speaker using the shortest and widest traces possible. Reducing trace length minimizes radiated EMI. Route SPKP/SPKN as a differential pair on the PCB to minimize the loop area and thereby the inductance of the circuit. If filter components are used on the speaker outputs, be sure to locate them as close as possible to the IC to ensure maximum effectiveness. Minimize the trace length from any ground tied passive components to PGND to further minimize radiated EMI. ���������������������������������������������������������������� Maxim Integrated Products 45 MAX97003 High-Efficiency, Low-Noise Audio Subsystem An evaluation kit (EV kit) is available to provide an example layout for the IC. The EV kit allows quick setup of the IC and includes easy-to-use software allowing all internal registers to be controlled. WLP Applications Information For the latest application details on WLP construction, dimensions, tape carrier information, PCB techniques, bump-pad layout, and recommended reflow temperature profile, as well as the latest information on reliability testing results, refer to the Application Note 1891: WaferLevel Packaging (WLP) and its Applications on Maxim’s website. Figure 23 shows the dimensions of the WLP balls used on the IC. Ordering Information 0.24mm PART TEMP RANGE PIN-PACKAGE MAX97003EWP+ -40NC to +85NC 20 WLP +Denotes a lead(Pb)-free/RoHS-compliant package. 0.21mm Figure 23. WLP Ball Dimensions ���������������������������������������������������������������� Maxim Integrated Products 46 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Package Information For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 20 WLP W201A2+1 21-0544 Refer to Application Note 1891 E PIN 1 INDICATOR COMMON DIMENSIONS MARKING 1 A3 A A1 AAAA D A2 0.05 S 0.64 0.05 A1 0.19 0.03 0.45 REF A2 A 0.025 BASIC A3 0.27 b S See Note 7 SIDE VIEW TOP VIEW A E1 SE 0.03 D1 1.20 BASIC E1 1.60 BASIC e 0.40 BASIC SD 0.20 BASIC SE 0.00 BASIC e B E D C B SD PKG. CODE D1 A 1 2 3 4 5 b 0.05 M S AB MIN D MAX MIN MAX DEPOPULATED BUMPS W201A2+1 2.33 2.36 1.92 1.95 NONE W201B2+1 2.16 2.19 1.60 1.63 NONE W201C2+1 2.01 2.04 1.61 1.64 NONE W201D2+1 2.08 2.11 1.71 1.74 NONE A BOTTOM VIEW NOTES: 1. Terminal pitch is defined by terminal center to center value. 2. Outer dimension is defined by center lines between scribe lines. 3. All dimensions in millimeter. 4. Marking shown is for package orientation reference only. 5. Tolerance is ± 0.02 unless specified otherwise. 6. All dimensions apply to PbFree (+) package codes only. 7. Front - side finish can be either Black or Clear. -DRAWING NOT TO SCALE- TITLE APPROVAL PACKAGE OUTLINE 20 BUMPS, WLP PKG. 0.4mm PITCH DOCUMENT CONTROL NO. 21-0544 REV. B 1 1 ���������������������������������������������������������������� Maxim Integrated Products 47 MAX97003 High-Efficiency, Low-Noise Audio Subsystem Revision History REVISION NUMBER REVISION DATE 0 9/11 DESCRIPTION Initial release PAGES CHANGED — Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2011 Maxim Integrated Products 48 Maxim is a registered trademark of Maxim Integrated Products, Inc.