Sharp LC-22LE240E, Service Manual

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LC-22LE240
2.3.2. Operating Specifications
2.4. Pinning
3. AUDIO AMPLIFIER STAGE WITH TPA3113(U168)
3.1. General Description
17MB62 uses a 6W Class D Mono Audio Amplifers for from 26” to 32” TVs. The
TPA3113D2 is a 6-W (per channel) efficient, Class-D audio power amplifier for driving
bridged-tied stereo speakers. Advanced EMI Suppression Technology enables the use of
inexpensive ferrite bead filters at the outputs while meeting EMC requirements.
SpeakerGuard™ speaker protection circuitry includes an adjustable power limiter and a
DC detection circuit. The adjustable power limiter allows the user to set a "virtual" voltage
rail lower than the chip supply to limit the amount of current through the speaker. The DC
detect circuit measures the frequency and amplitude of the PWM signal and shuts off the
output stage if the input capacitors are damaged or shorts exist on the inputs.
The TPA3113D2 can drive stereo speakers as low as 4 Ω. The high efficiency of the
TPA3113D2, 87%, eliminates the need for an external heat sink when
playing music.
The outputs are also fully protected against shorts to GND, VCC, and output-to-output.
The short-circuit protection and thermal protection includes an auto-recovery feature.