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 patented, low-EMI modulation scheme renders
the traditional class D output filter unnecessary.
The MAX9700 offers two modulation schemes: a fixedfrequency
(FFM) mode, and a spread-spectrum (SSM)
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 fullbridged
output, and 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 ✕ 3mm ✕ 0.8mm), 10-pin
μMAX, and 12-bump UCSP™ (1.5mm ✕ 2mm ✕ 0.6mm)
packages. The MAX9700 is specifie