13th Edition Audio Product Guide www.maximintegrated.com Audio Product Guide Table of Contents Speaker Amplifiers 3 Digital Input Class D Amplifiers 4 Tiny Speaker Amplifier Solution 5 Boosted Class D and Class DG Amplifiers 6 High-Power Speaker Amplifiers Headphone Amplifiers 82VRMS DirectDrive Amplifier 9 Class H Headphone Amplifiers Codecs 10 Codec Design Tools 11 Audio Codec with FlexSound Processor 12 Selection Guide 17 2 Class A–Class H Amplifier Tutorial www.maximintegrated.com www.maximintegrated.com Audio Product Guide Plug-and-Play Digital Input Class D Amplifiers The MAX98355A/MAX98355B and the MAX98356 are easy-to-use digital speaker amplifiers that improve audio quality, simplify design, and hasten time to market. They offer very high wideband jitter tolerance, low THD+N, and low output offset voltage to deliver superior performance and audio quality. These devices are easy to use because unique internal circuitry allows the parts to self-configure for sample rate and bit depth. This functionality eliminates the need for programming. The MAX98355A/MAX98355B and the MAX98356 do not require an MCLK signal, simplifying routing and allowing for a small 9-bump package. They also do not require a separate digital supply rail, thereby eliminating the need for an additional capacitor. MAX98355A/MAX98355B • Single-supply operation (2.5V to 5.5V) • 3.2W output power into 4Ω at 5V • 2.2mA quiescent current SHUTDOWN AND CHANNEL SELECT • 92% efficiency (RL = 8Ω, POUT = 900mW, VDD = 3.7V) • 25µVRMS output noise (AV = 15dB) MAX98355A MAX98355B GAIN CONTROL • Low 0.013% THD+N at 1kHz • No MCLK required • Supports left, right, or (left + right)/2 outputs PCM INPUT CLASS D OUTPUT STAGE DIGITAL AUDIO INTERFACE DAC SHUTDOWN AND CHANNEL SELECT MAX98356 GAIN CONTROL DIGITAL AUDIO INTERFACE DAC CLASS D OUTPUT STAGE MAX98356 • Single-supply operation (2.5V to 5.5V) • 3.2W output power into 4Ω at 5V • 1.7mA quiescent current • 92% efficiency (RL = 8Ω, POUT = 900mW, VDD = 3.7V) • 29µVRMS output noise (AV = 6dB) • Low 0.013% THD+N at 1kHz • Supports PDM_CLK rates of 1.8MHz to 4.32MHz and 5.28MHz to 8.6MHz • Supports left, right, or (left + right)/2 outputs PDM INPUT 3 www.maximintegrated.com Audio Product Guide Tiny Speaker Amplifiers for Space-Constrained Applications Small Size to Fit Your Application Maxim continues to lead the industry in innovative packaging technology that enables the smallest audio solutions. The Maxim family includes the industry's smallest Class AB and D amplifiers on the market in tiny 0.3mm pitch, 1mm x 1mm, 9-bump WLP packages. 3DMI Process Technology 3DMI process technology enables us to stack passive components directly onto the active substrate without increasing package height and area. This technology is used to integrate highly linear, input capacitors into the MAX98314, further reducing solution size, to save at least 25% more board space and provide excellent THD+N, PSRR, and CMRR performance at low frequencies. 3DMI technology opens doors to countless possibilities for future solutions. MAX98314 • 0.95mA at 3.7V low quiescent current • 3.2W into 4Ω, VPVDD = 5V • 19µV ultra-low noise • Spread spectrum and active emissions limiting Amplifier Class Power at 10% THD+N (W), RL = 4Ω MAX98304 Class D 3.2 1x1 MAX98309 Class AB 2.7 1x1 MAX98310 Class AB 1.4 MAX98314 Class D 2.7 Part MAX98314 CIN CLASS D MODULATOR AND H-BRIDGE UM 9-B P m 1 GAIN CONTROL 4 Package (mm x mm) 1x1 ✓ m x 1m m CIN Integrated Input Capacitors 1x1 www.maximintegrated.com Audio Product Guide Louder, Clearer Audio with Extended Battery Life The MAX98500/MAX98502 boosted Class D amplifiers and the MAX98307/MAX98308 Class DG amplifiers are designed for battery-operated portable devices. MAX98500/MAX98502 • Integrated boost converter to provide a constant output power for louder audio output over a wide range of battery supply voltages. • The automatic level control (ALC) has a battery tracking function that reduces output swing as the supply voltage drops, preventing collapse of the battery voltage. BATTERY VBAT B4 BOOST CONVERTER SDBST D4 SDSPK C3 GAIN B2 RKNEE LX A3 A2 VCCOUT MAX98500 CONTROL A1 PVDD B3 INP D2 INN D3 DIFFERENTIAL INPUT C4 AGND GAIN A4 BSTPGND OUTPUT STAGE B1 SPKP C1 SPKN D1, C2 SPKPGND MAX98307/MAX98308 • Class DG multilevel architecture offers highly efficient, high-power audio portable solutions. • Class DG multilevel architecture combines Class D switching output efficiency and Class G supply level shifting to more efficiently supply the required signal power. This allows for optimal efficiency over a wide output range. See the Class A– Class H Amplifier Tutorial. A Class DG amplifier improves upon Class AB by using a different power supply voltage depending on the signal level. Two or more voltages can be used, but all the voltages are available all the time. This is done by generating additional voltages from the single input voltage. Multiple Power Supply Voltages 5 www.maximintegrated.com Audio Product Guide No EMI Problems with Maxim's Class D Amplifiers Filterless Class D Amplifiers Provide the Output Power You Need With No EMI Hassles Maxim’s Class D amplifiers use patented spread-spectrum modulation techniques in conjunction with sophisticated edge-rate control technology to minimize EMI emissions. With no need for LC filters to clean up RF interference, your design will be compact, deliver solid performance, and cost less. INL- INL+ CLIPPING LIMITER CLASS D MODULATOR AND H-BRIDGE PGA MAX98400A MAX98400B MONO MAX98400A/MAX98400B • Wide 8V to 28V single-supply voltage range INR- INR+ OUTL+ Differential Input, Power Limiting, Thermal Foldback, Excellent EMI Performance, and Clipping Limiter OUTL- OUTRCLIPPING LIMITER PGA CLASS D MODULATOR AND H-BRIDGE OUTR+ • 2x20W into 8Ω or 1x40W into 4Ω (MAX98400A) or 2x12W into 8Ω (MAX98400B) • Optional 5V supply for efficiency optimization • Integrated edge rate control for low EMI for filterless operation • Clipping and power limiting • Two-pin, eight gain selector (9.1dB to 32.9dB) BIAS CLASS D AUDIO INPUT 20W Stereo/10W Mono Amplifier with I2C Volume Control CLASS D • Thermal foldback avoids thermal shutdown MAX9744/MAX9768 VOLUME CONTROL AUDIO INPUT MUTE • 4.5V to 14V supply voltage range • Filterless, low-EMI modulation scheme SHUTDOWN ANALOG OR I2C VOLUME CONTROL SYNC 6 • I2C or analog volume control MAX9744 OSCILLATOR SYNCOUT • High efficiency eliminates bulky heatsinks • High PSRR, low THD+N www.maximintegrated.com Audio Product Guide Maxim’s Class D Amplifier Family Extend Battery Life While Reducing EMI, Clipping, Noise, and Clicks and Pops Industry’s Lowest Supply Current Supply Current vs. Supply Voltage 4.0 The MAX98300 and the MAX98302 represent a substantial advancement in Class D amplifier power consumption by achieving supply current as low as 600µA. Critical to maximizing battery life in today’s portable products, this low supply current has been achieved without sacrificing EMI suppression, clipping behavior, noise performance, and click-and-pop level. In fact, these have all been improved. SUPPLY CURRENT (mA) 3.5 COMPETITION 3.0 2.5 2.0 1.5 MAX98300 1.0 0.5 0 Overdrive is No Problem—These Amplifiers Clip Cleanly In small consumer devices, both speakers and amplifiers are driven hard to yield the highest sound pressure level (SPL) possible. As a result, the amplifier may be heavily clipped. Many amplifier designs, particularly Class D designs, contribute additional high-frequency distortion artifacts that are far more objectionable than a cleanly clipped signal. The MAX98300 and the MAX98302 have been carefully designed to ensure clean recovery from clipping events. 2.5 3.0 3.5 4.0 4.5 5.0 SUPPLY VOLTAGE (V) 5.5 MAX98300 Heavy Clipping Recovery Low VOS for Low Click-and-Pop Noise Click-and-pop performance becomes important as we aggressively manage the power of amplifiers with frequent turn-on and turn-off cycles. If a pop or click is heard each time, it is annoying for the user. The MAX98300 has a very low offset voltage, and carefully addresses other sources of click-and-pop noise to ensure the best performance MAX98300 Filtered Output Voltage vs. SHDN VOUT 1mV (typ) SHDN MAX98300 EMI Spectrum (~24in Cable) 50.0 AMPLITUDE (dBμV/m) 40.0 EN55022B LIMIT 30.0 20.0 10.0 MAX98300 0.0 -10.0 30.0 100.0 200.0 300.0 400.0 500.0 600.0 700.0 800.0 900.0 1000.0 FREQUENCY (MHz) 7 www.maximintegrated.com Audio Product Guide 2VRMS DirectDrive Headphone Amplifier The MAX97220A-MAX97220E deliver excellent audio quality and performance. • Differential input reduces common input and ground noise • Output power 125mW into 32Ω with a 5V supply • 3VRMS output drive into 1kΩ with a 5V supply • 2VRMS output drive into 600Ω with a 3.3V supply • Fixed or externally adjustable gain with no clicks or pops • Wide 2.5V to 5.5V operating range • DirectDrive® outputs eliminate DC-blocking capacitors • High 112dB SNR and 90dB THD+N across audio bandwidth • Ground sense reduces noise, distortion, and crosstalk RF RIN LEFT AUDIO INPUT INLOUTL RIN INL+ RF RIN RIGHT AUDIO INPUT INL- OUTL RIN RF MAX97220A MAX97220B MAX97220E RF INR+ INR+ OUTR RIN LEFT AUDIO INPUT INL+ INR- RF RIN RIGHT AUDIO INPUT RIN MAX97220C MAX97220D RF SGND SGND OUTR INR- RIN RF RF 8 www.maximintegrated.com Audio Product Guide Ultra-Low Power Headphone Amplifiers Low-Power Class H Headphone Amplifiers Offer Higher Efficiency Class H amplifiers provide nearly 2x higher efficiency than the closest competitive Class G headphone amplifiers. Class H amps modulate the supply voltage to minimize voltage drop across the output devices by using either multiple supply voltages or an infinitely adjustable power supply. Enjoy Longer Battery Life Using Second-Generation, Dual-Mode, DirectDrive Technology Based on Maxim’s proprietary DirectDrive technology, our dual-mode DirectDrive II Class H amplifiers save power by switching between two supply voltages. The dual-mode charge pump uses ±0.9V rails when the output signal is small, only switching to ±1.8V supply voltage when more output power is needed. This technology renders a continuous signal without the glitches seen in Class G amplifiers. OUTPUT VOLTAGE +1.8V +0.9V 32ms HPVDD VTH_H TIME VTH_L -0.9V HPVSS 32ms -1.8V No clicks or pops MAX97200 LEFT AUDIO INPUT AUDIO SOURCE LEFT AUDIO OUTPUT SHDN RIGHT AUDIO INPUT RIGHT AUDIO OUTPUT 0.05% THD+N performance CHARGE PUMP Dynamic, Class H dual-mode charge pump 9 Audio Product Guide www.maximintegrated.com Customized Audio Made Easy MAX98089, MAX98090*, and MAX98091* Codec Design Tool Maxim’s evaluation kit and intuitive user interface allow you to tune flexible, feature-rich codecs to the desired performance quickly and easily. Optimize parametric EQ, automatic level control, speaker excursion limiter, speaker distortion THD limiter, microphone AGC, and microphone noise gate. 1) Download the codec GUI software. 2) Plug evaluation kit into your laptop. 3) Connect your headphones and speakers to the evaluation kit. 4) Graphically route and tune audio as you listen; register is set automatically. Software drivers are available for Linux and other OS platforms. *Future product—contact factory for availability. 10 www.maximintegrated.com Audio Product Guide Audio Codecs with Integrated Digital Signal Processing The MAX98089 and the MAX98090* full-featured audio codecs improve audio performance and prevent speaker damage. The parts feature Maxim’s proprietary FlexSound™ audio technology that optimizes the signal level and frequency response while limiting the maximum distortion and power at the output. This technology improves loudspeaker performance and prevents speaker damage. DIGITAL MICROPHONE DIGITAL AUDIO INTERFACE CONTROL REGISTERS 4 5 6 OR • MICROPHONE 2 PREAMP/PGA (DIFFERENTIAL) 3 ANALOG LINE INPUT MICROPHONE POWER MANAGEMENT MICROPHONE 1 PREAMP/PGA (DIFFERENTIAL) ANALOG LINE INPUT MICROPHONE OR I2C 1 2 OR ANALOG LINE INPUT MICROPHONE I2S/TDM STEREO DIGITAL MICOPHONE OR OR BATTERY 1.8V 1.2V • STEREO ADC LINE INPUT A PGA (DIFFERENTIAL OR SINGLE-ENDED) • • • FlexSound DSP DIGITAL BIQUAD FILTER (RECORD) 7-BAND PARAMETRIC EQUALIZER (PLAYBACK) DYNAMIC RANGE CONTROL (PLAYBACK) DIGITAL FILTERING DIGITAL GAIN/LEVEL CONTROL JACK DETECTION MAX98090* 3-POLE (TRS) 4-POLE (TRRS) Parametric EQ MAX98089 MAX98090*/ MAX98091* 5 band 7 band Distortion limiter Yes Yes Excursion limiter Yes Yes Integrated speaker amplifiers Yes Yes Integrated headphone amplifiers Yes Yes 2 3/3 Digital microphone inputs 2 2/4 Line inputs/line outputs 4 6 Analog microphone inputs Jack detection LINE OUTPUT OR RECEIVER/ EARPIECE SPEAKER LEFT CLASS D AMPLIFIER (DIFFERENTIAL) SPEAKER RIGHT CLASS D AMPLIFIER (DIFFERENTIAL) SPEAKER LEFT/RIGHT STEREO HEADPHONE CLASS H AMPLIFIER (SINGLE-ENDED) LINE INPUT B PGA (DIFFERENTIAL OR SINGLE-ENDED) Feature STEREO DAC STEREO LINE OUTPUT CLASS AB AMPLIFIER (SINGLE-ENDED) OR SPEAKER LEFT CLASS D AMPLIFIER (DIFFERENTIAL) Yes Yes Digital audio interfaces 2 1 Automatic level control Yes Yes Power limiter Yes Yes Microphone AGC Yes No Microphone noise gate Yes No CHARGE PUMP HEADPHONES OR HEADSET *Future product—contact factory for availability. 11 www.maximintegrated.com Audio Product Guide Class AB Speaker Amplifiers Part Supply Voltage (V) Output Power at 1% THD+N (W) Features 8Ω 4Ω Gain Other Package (mm x mm) MAX9710 4.5 to 5.5 2 x 1.5 2 x 2.6 Adj Mute 20-TQFN (5 x 5) MAX9711 4.5 to 5.5 1.5 2.6 Adj Mute 12-TQFN (4 x 4) 1.1 1.4 Adj Fixed Headphone sense 8-TDFN (3 x 3), 9-UCSP™ (1.5 x 1.5) 1.1 1.4 2 x 1.1 2 x 1.4 Adj Fixed Differential inputs 10-TDFN (3 x 3), 9-UCSP (1.5 x 1.5) MAX9716 MAX9717 MAX9718 MAX9719 2.7 to 5.5 2.7 to 5.5 MAX9730 2.7 to 5.5 2.4 — Adj Charge-pump-boosted amp for dynamic speakers 28-TQFN (4 x 4), 20-WLP (2 x 2.5) MAX9738 2.7 to 5.5 16VP-P — Adj DC-DC-boosted amp for ceramic speakers 20-WLP (2 x 2.5) MAX9788 2.7 to 5.5 20VP-P — Adj Charge-pump-boosted amp for ceramic speakers 28-TQFN (4 x 4), 20-WLP (2 x 2.5) 2.2 to 5.5 1.4 2.1 Differential inputs 9-WLP (1 x 1) MAX98309 MAX98310 Adj Fixed High-Power, Class D Speaker Amplifiers Part Supply Voltage (V) Output Power at 10% THD+N (W) Features 8Ω 4Ω Gain Other Package (mm x mm) MAX9708 10 to 18 2 x 20 40 Pin programmable Programmable thermal flag 56-TQFN (8 x 8) MAX9709 10 to 22 2 x 25 50 Pin programmable Programmable thermal flag 56-TQFN (8 x 8) MAX9736A 8 to 28 2 x 15 30 Set by external resistors Mute function 32-TQFN (7 x 7) MAX9736B 8 to 28 2x6 12 Set by external resistors Mute function 32-TQFN (7 x 7) MAX9737 8 to 28 7.4 14 Set by external resistors Mute function 24-TQFN (4 x 4) MAX9742 20 to 40 2 x 20 2 x 16 Set by external resistors Single-ended output 36-TQFN (6 x 6) MAX9744 MAX9768 4.5 to 14 2 x 13 2 x 20 Set by external resistors I2C/analog volume control 44-TQFN (7 x 7) I2C/analog volume control 24-TQFN (4 x 4) 4.5 to 14 10 — Set by external resistors MAX98400A* 8 to 28 2 x 20 40 Pin programmable Clipping limiter 36-TQFN (6 x 6) MAX98400B* 8 to 28 2 x 12 — Pin programmable Clipping limiter 24-TQFN (4 x 4) *JEITA (Japan Electronics and Information Technology Industries Association) standard, “A Guide to the Safe Use of Secondary Lithium Ion Batteries in Notebook-type Personal Computers”, April 20, 2007. 12 www.maximintegrated.com Audio Product Guide Low-Power, Class D Speaker Amplifiers (Filterless) Output Power at 1% THD+N (W) Part Supply Voltage (V) Features 8Ω 4Ω SpreadSpectrum/ Edge-Rate Control Gain Package (mm x mm) Differential Input MAX9715 4.5 to 5.5 2 x 1.4 2 x 2.3 ✓/— Pin programmable 16-TQFN (5 x 5) MAX9759 3.0 to 5.5 1.4 2.6 ✓/— Pin programmable ✓ 16-TQFN (4 x 4) MAX9830 2.6 to 5.5 1.3 1.7 ✓/✓ Fixed ✓ 8-TDFN (2 x 2), 9-WLP (1.2 x 1.2) MAX98300 2.6 to 5.5 1.3 2.1 ✓/✓ Pin programmable ✓ 8-TDFN (2 x 2), 9-WLP (1.2 x 1.2) MAX98302 2.6 to 5.5 2x1 2x2 ✓/✓ Pin programmable ✓ 14-TDFN (3 x 3) MAX98304 2.6 to 5.5 1.4 2.6 ✓/✓ Pin programmable ✓ 9-WLP (1.0 x 1.0) MAX98306 2.6 to 5.5 2 x 1.4 2 x 2.4 ✓/✓ Pin programmable ✓ 14-TDFN (3 x 3) MAX98314 2.6 to 5.5 1.4 2.6 ✓/✓ Pin programmable ✓ 9-WLP (1.0 x 1.0) MAX98500 2.5 to 5.5 1.7 — ✓/✓ Pin programmable ✓ 16-WLP (2.1 x 2.1) MAX98502 2.5 to 5.5 1.7 3.4 ✓/✓ Pin programmable ✓ 16-WLP (2.1 x 2.1) Digital Input Class D Speaker Amplifiers Part Supply Voltage (V) Output Power at 1% THD+N (W) Features 8Ω 4Ω Gain Input Type Package (mm x mm) MAX98355A/ MAX98355B 2.5 to 5.5 1.4 2.5 3, 6, 9, 12, 15 PCM 9-WLP (1.3 x 1.5) MAX98356 2.5 to 5.5 1.4 2.5 3, 6, 9, 12, 15 PDM 9-WLP (1.3 x 1.5) 13 www.maximintegrated.com Audio Product Guide Capless, DirectDrive Headphone Amplifiers Supply Voltage (V) Supply Current (mA) Output Offset (mV) MAX4409 1.8 to 3.6 5.0 MAX4410/ MAX4411 1.8 to 3.6 MAX9722 Part Output Power at 1% THD+N (mW) Package (mm x mm) Features 32Ω 16Ω 0.5 65 80 Ground noise rejection 5.0 0.5 65 80 Ultra-low distortion 2.4 to 5.5 5.5 0.5 130 70 Differential inputs MAX9724 2.7 to 5.5 3.5 1.5 63 42 Industry's lowest RF susceptibility MAX9820 2.7 to 5.5 3.0 0.1 95 70 Windows Vista® premium mobile compliant 10-TDFN (3 x 3) 1.6 to 2 1.15 0.1 34 40 Lowest quiescent current 12-WLP (1.7 x 1.3) 110 2VRMS into 600Ω differential outputs MAX97200 MAX97220– MAX97220E 2.5 to 5.5 5.0 0.35 125 20-TQFN (4 x 4) 16-UCSP (2 x 2), 20-TQFN (4 x 4) 16-TQFN (3 x 3) 12-TQFN (3 x 3), 12-UCSP (1.5 x 2) 16-TQFN (3 x 3 x 0.8) Audio Data Converters Supply Voltage (V) Part 48kHz DAC Playback Power Consumption (mW) Playback Dynamic Range (dB) Features Digital Audio Interface MCLK Range (MHz) Supported Sample Rates (kHz) Package (mm x mm) I2S 8.5 to 40 8 to 48 28-TQFN (5 x 5) 3 line inputs, 3 microphone inputs, 2 line outputs, 2 headphone amps I2S/TDM 10 to 60 8 to 96 40-TQFN (6 x 6) 90 2 microphone inputs, 1 headphone amp I2S/TDM 10 to 60 8 to 48 24-TQFN (4 x 4) 5.5 92 2 line inputs, 2 microphone inputs, 2 headphone amps, 1 aux ADC I2S/TDM 10 to 60 8 to 48 30-WLP (2 x 2.5), 32-TQFN (5 x 5) 5.5 101 4 line inputs, 3 microphone inputs, 2 headphone amplifiers, 2 speaker amplifiers I2S/TDM 10 to 60 8 to 96 63-WLP, 56-TQFN 102 6 line inputs, 3 microphone inputs, 2 headphone amplifiers, 2 speaker amplifiers I2S/TDM 8 to 96 8 to 96 49-WLP, 40-TQFN 102 6 line inputs, 4 microphone inputs, 2 headphone amplifiers, 2 speaker amplifiers I2S/TDM 8 to 96 8 to 96 56-WLP Core I/O MAX9850 (DAC) 1.8 to 3.6 1.8 to 3.6 10.1 91 2 line inputs, 2 line outputs, 2 headphone amps MAX9856 (codec) 1.7 to 3.6 1.7 to 3.6 9 91 MAX9860 (codec) 1.7 to 1.9 1.7 to 3.6 4.5 MAX9867 (codec) 1.65 to 1.95 1.65 to 3.6 MAX98089 (codec) 1.65 to 3.6 1.65 to 2.0 MAX98090* (codec) 1.65 to 3.6 MAX98091* (codec) 1.65 to 3.6 1.65 to 2 1.65 to 2 *Future product—contact factory for availability. 14 3.6 3.6 Analog I/O www.maximintegrated.com Audio Product Guide Microphone Amplifiers With Integrated Mic Bias Features Supply Voltage (V) Supply Current (µA) InputNoise Voltage Density (nV/√Hz) SingleEnded Differential MAX4060 4.5 to 5.5 750 100 1 1 Adj 8-TDFN (3 x 3) MAX4061 2.4 to 5.5 750 20 1 1 0dB, 20dB, 40dB 8-TDFN (3 x 3) MAX4063 2.4 to 5.5 750 12 1 1 Adj 16-TQFN (4 x 4) MAX4465/ MAX4466 2.4 to 5.5 24 80 1 Adj ✓ 5-SC70 (2 x 2), 5-SOT23 (3 x 3) MAX9812L/ MAX9813L 2.7 to 3.6 230 40 2 20dB ✓ 6-SC70 (2 x 2.1) (MAX9812), 8-SOT23 (3 x 3) (MAX9813) MAX9812H/ MAX9813H 4.5 to 5.5 230 40 2 20dB ✓ 6-SC70 (2 x 2.1) (MAX9812), 8-SOT23 (3 x 3) (MAX9813) MAX9814 2.7 to 5.5 3100 30 1 Automatic gain control ✓ 14-TDFN (3 x 3) Part Inputs Gain Shutdown Mode Package (mm x mm) Specialty Audio Devices Part MAX9890 Supply Voltage (V) Description Package (mm x mm) 2.7 to 5.5 Headphone-amp click-pop suppressor 8-TDFN (3 x 3), 9-UCSP (1.5 x 1.5) MAX9892 1.7 to 3.6 Audio shunt-mode click-pop suppressor 6-UCSP (1 x 1.5), 6-µDFN (2 x 2) MAX4744 1.8 to 5.5 Dual SPDT audio switch 10-µDFN (2 x 2) MAX4764 1.8 to 5.5 Dual SPDT audio switch 10-TDFN (3 x 3), 10-UCSP (1.5 x 2) MAX4993/ MAX4994 1.8 to 5.5 DPDT audio switch 10-UTQFN (1.4 x 1.8) MAX9895A* 2.5 to 4.5 Active noise-cancellation solution for stereo headphones 36-WLP (2.5 x 2.5 x 0.4), 40-TQFN (5 x 5) *Future product—contact factory for availability. 15 www.maximintegrated.com Audio Product Guide Integrated Audio Subsystems Output Power at 1% THD+N* Part Supply Voltage (V) HP 32Ω (mW) HP 16Ω (mW) SP 8Ω (W) Features SP 4Ω (W) Gain/Volume Control Package (mm x mm) Speaker Amplifier Other Stereo Class D 6 single-ended or 3 differential audio inputs, 3D sound 36-UCSP (3 x 3) MAX9775 2.7 to 5.5 50 60 2 x 1.1 2 x 1.5 I2C MAX9776 2.7 to 5.5 50 60 1.1 1.5 I2C Mono Class D 6 single-ended or 3 differential audio inputs, 3D sound 36-UCSP (3 x 3), 32-TQFN (5 x 5) MAX9789 4.5 to 5.5 55 100 2x1 2x2 Pin programmable Stereo Class AB Integrated LDO 32-TQFN (5 x 5) MAX9791 2.7 to 5.5 180 100 2 x 1.2 2 x 1.7 Adj Stereo Class D Wake-on-beep, ground sense, integrated LDO 28-TQFN (4 x 4) MAX9792 2.7 to 5.5 180 100 1.5 2.5 Adj Mono Class D Wake-on-beep, ground sense, integrated LDO 28-TQFN (4 x 4) Mono Class D 6 single-ended or 3 differential audio inputs, 3D sound 32-TQFN (5 x 5) MAX9796 2.7 to 5.5 50 60 1.3 2.3 I2C MAX9877 2.7 to 5.25 27 53 0.725 0.825 I2C Mono Class D 2 stereo or 2 mono differential audio inputs 20-WLP (2 x 2.5) MAX9879 2.7 to 5.5 54 58 2 x 0.715 2x 0.825 I2C Stereo Class D 2 stereo or 2 mono differential audio inputs 30-UCSP (2.5 x 3) Mono Class D Integrated LDO, bypass switch, THD limiter, Class H headphone amp 25-WLP (2 x 2 x 0.4) Mono Class D Bypass switch, THD limiter, Class H headphone amp 20-WLP (2 x 2.5) Mono Class D Class H headphone amp, 2 stereo singleended/mono differential inputs 20-WLP (2 x 2.5) MAX97000 2.7 to 5.5/ 1.7 to 2.0 MAX97001 2.7 to 5.5/ 1.6 to 2.0 MAX97003 2.7 to 5.5 *HP = headphone, SP = speaker 16 23 34 32 40 43 42 0.930 I2C 0.710 I2C 1 2.5 I2C www.maximintegrated.com Audio Product Guide Class A–Class H Amplifier Tutorial Class A The simplest type of amplifiers, Class A amplifiers, are those in which the output transistors conduct (i.e., do not fully turn off), irrespective of the output signal waveform. This type of amplifier is typically associated with high linearity, but low efficiency. Class B Class B amplifiers are those in which the output transistors only conduct during half (180°) of the signal waveform. To amplify the entire signal, they use two transistors, one conducting for positive output signals and the other conducting for negative outputs. Class B amplifiers are much more efficient than Class A amplifiers, but they have high distortion due to the crossover point at which the two transistors transition from on to off. Class AB A combination of Class A and Class B, the Class AB amplifier has higher efficiency than Class A, but less distortion than Class B. This performance is achieved by biasing both transistors to conduct near zero signal output—the point where Class B amplifiers introduce nonlinearities. They then transition to Class B for large excursions. Thus, for small signals, both transistors are active, acting like a Class A amplifier. For large signal excursions, only one transistor is active for each half of the waveform, acting like a Class B amplifier. Class D CLASS D MODULATOR CLASS D MOSFET MODULATOR DRIVER MOSFET DRIVER Class D amplifiers are those that output a switching waveform at a frequency far higher than the highest audio signal that needs to be reproduced. The lowpass-filtered average value of this waveform CLASS D MOSFET corresponds to the actual required waveform. These amplifiers MODULATORaudio DRIVER are highly efficient (often up to 90% or higher) because the output transistors are either fully turned on or off during operation. This approach completely eliminates the use of the linear region of the transistor, which is responsible for the inefficiency of other amplifier types. Modern Class D amplifiers achieve fidelity comparable to CLASS D MOSFET MODULATOR DRIVER Class AB. 17 +V1+V2 www.maximintegrated.com Audio Product Guide +V1 +V2 Class A–Class H Amplifier Tutorial (cont.) -V2 -V1 -V1 -V2 Class G +V1+V2 Class G amplifiers are similar to Class AB amplifiers, except that they use two or more supply voltages. When operating at low signal levels, the amplifier selects a low supply voltage. As the signal level increases, the amplifier automatically +V1 selects the appropriate supply voltage. Class G amplifiers are more efficient than Class AB amplifiers because they use the maximum supply voltage only when required, while a Class AB amplifier always uses the maximum supply voltage. +V1 +V2 -V2 -V1 +V1 -V1 -V1 -V2 -V1 +V1 Class DG +V1+V2 +V1 +V2 CLASS D MODULATOR MOSFET DRIVER -V2 -V1 +V1+V2 Class DG uses pulse-width modulation (PWM), a rail-to-rail +V1 digital output signal with variable duty cycle, to approximate an analog input signal as in a Class D amplifier. The Class -V1 +V1 DG multilevel output stage also senses the magnitude of the output signal and switches the supply rails+V2 as needed to more efficiently supply the required signal power. -V2 -V1 -V1 -V2 -V1 -V1 -V2+V1+V2 +V1 +V2 Class H CLASS D MODULATOR MOSFET DRIVER Class H amplifiers modulate their supply voltage to minimize the voltage drop across the output stage. Implementations range from using multiple discrete voltages to an infinitely adjustable supply. Though similar to the Class G technique of reducing dissipation across output devices, the Class H technique does not require multiple power supplies. Class H amplifiers are generally more complex than other designs, with extra control circuitry required to predict and control the supply voltage. -V2 +V1 -V1 -V1 -V2 +V1 -V1 -V1 +V1+V2 +V1 +V2 18 CLASS D MODULATOR MOSFET DRIVER -V2 -V1 www.maximintegrated.com Audio Product Guide Theoretical Output Power The following figure shows the theoretical output power possible from a range of supply voltages. Output power is specified at 1% and 10% THD+N with 4Ω and 8Ω loads. Real amplifiers will always output less power than shown in this figure. Output Power vs. Supply Voltage 100 4Ω BTL, 10% THD+N 4Ω BTL, 1% THD+N 8Ω BTL, 10% THD+N OUTPUT POWER (W) 10 8Ω BTL, 1% THD+N 1 0.1 3 8 13 18 23 28 SUPPLY VOLTAGE (V) 19 Audio Product Guide DirectDrive is a registered trademark and registered service mark and FlexSound and UCSP are trademarks of Maxim Integrated Products, Inc. Windows Vista is a registered trademark and registered service mark of Microsoft Corporation. Contact Maxim Direct at 1.800.629.4642 or for more information, visit www.maximintegrated.com. © 2012 Maxim Integrated. All rights reserved. The Maxim logo and Maxim Integrated are trademarks of Maxim Integrated Products, Inc. in the United States and other jurisdictions throughout the world. All other company names may be trade names or trademarks of their respective owners. Rev. 0; December 2012 www.maximintegrated.com