Sharp LC-19LE510E, Service Manual

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LC-19LE510
LC-22LE510
LC-24LE510
6. AUDIO AMPLIFIER STAGE WITH TPA3113(U168)
6.1.General Description
17MB60 uses a 6W Class D Mono Audio Amplifiers 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.
6.2.Features

6-W/ch into an 8-
Ω
Loads at 10% THD+N From a 10-V Supply

12-W into a 4-
Ω
Mono Load at 10% THD+N From a 10-V Supply

87% Efficient Class-D Operation Eliminates Need for Heat Sinks

Wide Supply Voltage Range Allows Operation from 8 V to 26 V

Filter-Free Operation
 SpeakerGuard™ Speaker Protection Includes Adjustable Power Limiter plus DC Protection

Flow Through Pin Out Facilitates Easy Board Layout
 Robust Pin-to-Pin Short Circuit Protection and Thermal Protection with Auto Recovery
Option
 Excellent THD+N / Pop-Free Performance

Four Selectable, Fixed Gain Settings
 Differential inputs
6.3.Absolute Ratings
6.3.1.Electrical Characteristics
6.3.2.Operating Specifications