The MAX9723 stereo DirectDrive? headphone amplifier
with BassMax and volume control is ideal for portable
audio applications where space is at a premium and performance
is essential. The MAX9723 operates from a single
1.8V to 3.6V power supply and includes features that
reduce external component count, system cost, board
space, and improves audio reproduction.
The headphone amplifier uses Maxim’s patented
DirectDrive architecture that produces a ground-referenced
output from a single supply, eliminating the need
for large DC-blocking capacitors. The headphone amplifiers
deliver 62mW into a 16Ω load, feature low 0.006%
THD+N, and high 90dB PSRR. The MAX9723 features
Maxim’s industry-leading click-and-pop suppression.
The BassMax feature boosts the bass response of the
amplifier, improving audio reproduction when using
inexpensive headphones. The integrated volume control
features 32 discrete volume levels, eliminating the
need for an external potentiometer. BassMax and the
volume control are enabled through the I2C/SMBus?-
compatible interface. Shutdown is controlled through
either the hardware or software interfaces.
The MAX9723 consumes only 3.7mA of supply current
at 1.8V, provides short-circuit and thermal-overload
protection, and is fully specified over the extended
-40°C to +85°C temperature range. The MAX9723 is
available in a tiny (2mm x 2mm x 0.62mm) 16-bump
chip-scale package (UCSP?) or 16-pin thin QFN (4mm
x 4mm x 0.8mm) package.