MAX9700, MAX9700A, MAX9700B, MAX9700C, MAX9700D

1.2W, Low-EMI, Filterless, Class D Audio Amplifier

1.2W, Low-EMI, Filterless, Class D Audio Amplifiers Provide Class AB Amplifier Performance with Class D Efficiency, Conserving Board Space and Extending Battery Life

Please check latest availability status for a specific part variant.


The MAX9700 mono class D audio power amplifier provides class AB amplifier performance with class D efficiency, conserving board space and extending battery life. Using a class D architecture, the MAX9700 delivers 1.2W into an 8Ω load while offering efficiencies above 90%. A low-EMI modulation scheme renders the traditional class D output filter unnecessary.

The MAX9700 offers two modulation schemes: a fixed-frequency (FFM) mode, and a spread-spectrum mode that reduces EMI-radiated emissions due to the modulation frequency. Furthermore, the MAX9700 oscillator can be synchronized to an external clock through the SYNC input, allowing the switching frequency to be user defined. The SYNC input also allows multiple MAX9700s to be cascaded and frequency locked, minimizing interference due to clock intermodulation. The device utilizes a fully differential architecture, a full-bridged output, and full-bridged comprehensive click-and-pop suppression. The gain of the MAX9700 is set internally (MAX9700A: 6dB, MAX9700B: 12dB, MAX9700C: 15.6dB, MAX9700D: 20dB), further reducing external component count.

The MAX9700 features high 72dB PSRR, a low 0.01% THD+N, and SNR in excess of 90dB. Short-circuit and thermal-overload protection prevent the device from damage during a fault condition. The MAX9700 is available in 10-pin TDFN (3mm x 3mm x 0.8mm), 10-pin µMAX® and 12-bump UCSP™ (1.5mm x 2mm x 0.6mm) packages. The MAX9700 is specified over the extended -40°C to +85°C temperature range.
MAX9700, MAX9700A, MAX9700B, MAX9700C, MAX9700D: Functional Diagram MAX9700, MAX9700A, MAX9700B, MAX9700C, MAX9700D: Functional Diagram Enlarge+

Key Features

  • Filterless Amplifier Passes FCC Radiated Emissions Standards with 100mm of Cable
  • Unique Spread-Spectrum Mode Offers 5dB Emissions Improvement Over Conventional Methods
  • Optional External SYNC Input
  • Simple Master-Slave Setup for Stereo Operation
  • 94% Efficiency
  • 1.2W into 8Ω
  • Low 0.01% THD+N
  • High PSRR (72dB at 217Hz)
  • Integrated Click-and-Pop Suppression
  • Low Quiescent Current (4mA)
  • Low-Power Shutdown Mode (0.1µA)
  • Short-Circuit and Thermal-Overload Protection
  • Available in Thermally Efficient, Space-Saving Packages
    • 10-Pin TDFN (3mm x 3mm x 0.8mm)
    • 10-Pin µMAX
    • 12-Bump UCSP (1.5mm x 2mm x 0.6mm)


  • Cell Phones
  • MP3 Players
  • PDAs
  • Portable Audio

MAX9700BEVKIT: Evaluation Kit for the MAX9700A, MAX9700B, MAX9700C, MAX9700D, and MAX9712

Technical Documents

Tutorial 4691 Introduction to Hearing Aids and Important Design Considerations
Tutorial 4675 Important Considerations for Insulin Pump and Portable Medical Designs
App Note 4551 Simple Circuit Limits Amplifier's Output
App Note 3977 Class D Amplifiers: Fundamentals of Operation and Recent Developments

Quality and Environmental Data

Product Reliability Reports: MAX9700.pdf  MAX9700A.pdf  MAX9700B.pdf 
Request Reliability Report for: MAX9700C  MAX9700D 
Lead-Free Package Tin (Sn) Whisker Reports

Additional Resources

Topmark Coding MAX9700A
Topmark Coding MAX9700B
Topmark Coding MAX9700C
Topmark Coding MAX9700D
Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C  

Note : The failure rates are summarized by technology and mapped to the associated material part numbers. The failure rates are highly dependent on the number of units tested.

Quality Management System >
Environmental Management System >


Related Resources

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