General Description

The MAX9721 fixed-gain, stereo headphone amplifier is ideal for portable equipment where board space is at a premium. The MAX9721 uses a unique, patented DirectDrive architecture to produce a ground-referenced output from a single supply, eliminating the need for large DC-blocking capacitors, saving cost, board space, and component height. Fixed gains of -2V/V (MAX9721A), -1.5V/V (MAX9721B), and -1V/V (MAX9721C) further reduce external component count.

Features

? Single Cell, 0.9V to 1.8V Single-Supply Operation

? Fixed Gain Eliminates External Feedback Network

??? MAX9721A: -2V/V

??? MAX9721B: -1.5V/V

??? MAX9721C: -1V/V

? Ground-Referenced Outputs Eliminate DC Bias

? No Degradation of Low-Frequency Response Due to Output Capacitors

? 20mW per Channel into 32?

? Low 0.006 THD+N

? High PSRR (80dB at 1kHz)

? Integrated Click-and-Pop Suppression

? Low Quiescent Current (2.2mA)

? Low-Power Shutdown Control

? Short-Circuit Protection

? ±8kV ESD-Protected Amplifier Outputs

? Available in Space-Saving Packages

??? 12-Bump UCSP (1.54mm x 2.02mm x 0.6mm)

??? 12-Pin Thin QFN (4mm x 4mm x 0.8mm)

Applications

??? MP3 Players

??? Cellular Phones

??? PDAs

??? Smart Phones

??? Portable Audio Equipment