Audio Amplifier Stage With Max9736; General Description; Features - Sharp LC-40LE530E Service Manual

5. AUDIO AMPLIFIER STAGE WITH MAX9736

5.1.

General Description

The MAX9736A/B Class D amplifiers provide high-performance, thermally efficient amplifier solutions.
The MAX9736A delivers 2 x 15W into 8
devices are pinfor-pin compatible, allowing a single audio design to work across a broad range of
platforms, simplifying design efforts, and reducing PCB inventory.
Both devices operate from 8V to 28V and provide a high PSRR, eliminating the need for a regulated
power supply. The MAX9736 offers up to 88% efficiency at 12V supply.
Pin-selectable modulation schemes select between filterless modulation and classic PWM
modulation. Filterless modulation allows the MAX9736 to pass CE EMI limits with 1m cables using
only a low-cost ferrite bead and capacitor on each output. Classic PWM modulation is optimized for
best audio performance when using a full LC filter.
A pin-selectable stereo/mono mode allows stereo operation
loads. In mono mode, the right input op amp becomes available
as a spare device, allowing flexibility in system design.
Comprehensive click-and-pop reduction circuitry minimizes noise coming into and out of shutdown or
mute. Input op amps allow the user to create summing amplifiers,
lowpass or highpass filters, and select an optimal gain.
The MAX9736A/B are available in 32-pin TQFN packages and specified over the -40°C to +85°C
temperature
range.
5.2.

Features

Wide 8V to 28V Supply Voltage Range
Spread-Spectrum Modulation Enables Low EMI Solution
Passes CE EMI Limits with Low-Cost Ferrite Bead/Capacitor Filter
Low BOM Cost, Pin-for-Pin Compatible Family
High 67dB PSRR at 1kHz Reduces Supply Cost
88% Efficiency Eliminates Heatsink
Thermal and Output Current Protection
< 1 A Shutdown Mode
Mute Function
Space-Saving, 7mm x 7mm x 0.8mm, 32-Pin TQFN
Package
25
LC-32LE530
LC-40LE530