Sharp LC-32LD145K, Service Manual

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LC-39LD145
LC-32LD145
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2. AUDIO AMPLIFIER STAGE
TAS5721 (optional)
2.1. General Description
The TAS5721 is a 15-W stereo or 2x10 W + 1x15 W2.1 device, efficient, digital audio-power
amplifier fordriving stereo bridge-tied speakers. One serial datainput allows processing of
up to two discrete audiochannels and seamless integration to most digitalaudio processors
and MPEG decoders. The deviceaccepts a wide range of input data and data rates. Afully
programmable data path routes these channelsto the internal speaker drivers.The TAS5721
is a slave-only device receiving allclocks from external sources. The TAS5721 operateswith
a PWM carrier between a 384-kHz switching rateand a 352-KHz switching rate, depending
on the inputsample rate. Oversampling combined with a fourth- order noise shaper provides
a flat noise floorand excellent dynamic range from 20 Hz to 20 kHz.
2.2. Features
• Audio Input/Output
– 15Wx2 into 8

– Supports Single Device 0.1, 2.0, 2.1 Modes
– Wide PVDD Range, From 4.5 V to 26 V Performance
– Efficient Class-D Operation Eliminates Need for Heatsinks
– Requires Only 3.3 V and PVDD
– One Serial Audio Input (Two Audio Channels)
– I2C Address Selection via PIN (Chip Select)
– Supports 8-kHz to 48-kHz Sample Rate (LJ/RJ/I2S)
– External Headphone-Amplifier Shutdown Signal
– Integrated CAP-Free Headphone Amplifier
– Stereo Headphone (Stereo 2-V RMS Line Driver) Outputs
• Audio/PWM Processing
– Independent Channel Volume Controls With The 24-dB to Mute
– Separate Dynamic Range Control for Satellite and Sub Channels
– 21 Programmable Biquads for Speaker EQ
– Programmable Coefficients for DRC Filters
– DC Blocking Filters
– Support for 3D Effects
• General Features
– Serial Control Interface Operational Without MCLK
– Factory-Trimmed Internal Oscillator for Automatic Rate Detection
– Surface Mount, 48-Pin, 7-mm × 7-mm HTQFP Package
– Thermal and Short-Circuit Protection
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