The MAX5406 stereo audio processor provides a complete audio solution with volume, balance, bass, and treble controls. It features dual 32-tap logarithmic potentiometers for volume control, dual potentiometers for balance control, and linear digital potentiometers for tone control. A simple debounced pushbutton interface controls all functions. The MAX5406 advances the wiper setting once per button push. Maxim’s proprietary SmartWiper™ control eliminates the need for a microcontroller (µC) to increase the wiper transition rate. Holding the control input low for more than 1s advances the wiper at a rate of 4Hz for 4s and 16Hz thereafter. An integrated click/pop suppression feature eliminates the audible noise generated by the wiper’s movements. The MAX5406 provides a subwoofer output that internally combines the left and right channels. An external filter capacitor allows for a customized cut-off frequency for the subwoofer output. A bass-boost mode enhances the low-frequency response of the left and right channels. An integrated bias amplifier generates the required (VDD + VSS) / 2 bias voltage, eliminating the need for external op amps for unipolar operation. The MAX5406 also features ambience control to enhance the separation of the left- and right-channel outputs for headphones and desktop speakers systems, and a pseudostereo feature that approximates stereo sound from a monophonic signal.
The MAX5406 audio processor provides a complete solution for stereo audio handling, featuring dual 32‑tap logarithmic potentiometers for volume, dual potentiometers for balance, and linear digital potentiometers for tone control. All functions are operated via a debounced push‑button interface and Maxim’s SmartWiper™ technology, which eliminates the need for a microcontroller.
The device is available in a 7 mm × 7 mm, 48‑pin TQFN package and a 48‑pin TSSOP package, operates over a –40 °C to +85 °C temperature range, and supports single‑supply (+2.7 V to +5.5 V) or dual‑supply (±2.7 V) operation. Key performance figures include < ‑90 dB mute attenuation, > ‑70 dB channel isolation, and 0.02 % typical THD into a 10 kΩ load.
| Supply Voltage | +2.7 V to +5.5 V (single) or ±2.7 V (dual) |
|---|---|
| Volume Control Resolution | 32‑tap logarithmic potentiometer, 2 dB steps |
| Mute Attenuation | < ‑90 dB (typ) |
| Channel Isolation | > ‑70 dB (typ) |
| THD (10 kΩ Load) | 0.02 % (typ) at 1 kHz |
The MAX5406 can be powered from a single supply of +2.7 V to +5.5 V or from a dual supply of ±2.7 V.
The device provides 32 logarithmic volume steps, each representing a 2 dB change.
Typical total harmonic distortion is 0.02 % into a 10 kΩ load at 1 kHz.
The mute function attenuates the audio signal by less than –90 dB (typ).