MAX9726BETP+T

Audio Amplifiers Overview

The MAX9726BETP+T is a stereo DirectDrive headphone amplifier from Analog Devices/Maxim Integrated, designed for portable audio applications. It operates on a single 2.7V to 5.5V supply and delivers 105mW into a 32Ω load with 0.02% THD+N. The device features an integrated inverting charge pump that creates a negative supply rail, enabling ground-referenced outputs without bulky DC-blocking capacitors. Key specifications include 85dB PSRR at 1kHz, 5.5mA quiescent current, and 8μA shutdown current. It incorporates software-controlled BassMax bass boost, a 64-level digital volume control via I²C/SMBus, and industry-leading click-and-pop suppression.

Audio Amplifiers Feature Summary

• DirectDrive architecture eliminates the need for large external DC-blocking capacitors by generating an internal negative supply rail.
• Integrated 64-level digital volume control and software-enabled BassMax bass boost accessible via I²C/SMBus interface.
• Advanced click-and-pop suppression circuitry minimizes audible transients during power-up and power-down transitions.
• High 85dB power-supply rejection ratio allows direct connection to battery-powered supplies without dedicated LDOs.

Audio Amplifiers Applications

• Portable audio devices requiring space-constrained designs
• Battery-powered consumer electronics needing low-power operation
• Applications demanding high-fidelity audio reproduction with minimal external components

Audio Amplifiers Procurement Notes

Verify the specific suffix 'T' indicates tape and reel packaging when ordering. Confirm the 'B' variant designation matches the required slave address configuration for your system design. Ensure compatibility with the 20-pin TQFN footprint dimensions during PCB layout. Cross-reference the lead-free status (+) with environmental compliance requirements for your target market.

Audio Amplifiers Selection Notes

Select this component for designs prioritizing board space reduction through the elimination of output coupling capacitors. Consider the 20-pin TQFN package for its thermal efficiency and compact form factor compared to UCSP alternatives. Evaluate the I²C interface requirements against your microcontroller's available serial ports. Assess the 105mW output capability against your specific headphone impedance and desired maximum volume levels.

Audio Amplifiers Part Context

The MAX9726 belongs to Maxim Integrated's DirectDrive family of headphone amplifiers. This series focuses on integrating charge pumps to enable single-supply operation with ground-referenced outputs. The MAX9726 specifically adds digital control features like volume adjustment and bass boost, distinguishing it from basic amplifier variants within the same architectural lineage.

Audio Amplifiers Replacement Considerations

The MAX9726AETP+ serves as a functional alternative with a different I²C slave address (1001100 vs 1001101). Verify software compatibility if substituting between the A and B variants due to the address difference.

Audio Amplifiers FAQ

How does the DirectDrive architecture affect external component count?

The DirectDrive architecture uses an internal charge pump to create a negative supply rail, allowing ground-referenced outputs. This eliminates the need for large external DC-blocking capacitors typically required by conventional single-supply amplifiers.

What is the mechanism for controlling the volume level?

Volume is controlled digitally via the I²C/SMBus-compatible interface. The internal command register allows selection among 64 discrete attenuation levels, eliminating the need for an external potentiometer.

How is the BassMax feature implemented?

BassMax is enabled or disabled via the I²C interface. When enabled, it boosts low-frequency response by feeding a filtered version of the output signal back to the amplifier inputs using external passive components connected to the BM_ pins.