Sharp LC-42LE761K Service Manual ▷ View online
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3. AUDIO AMPLIFIER STAGES
A. MAIN AMPLIFIER (TAS5719)
a. General Description
The TAS5717/TAS5719 is a 10-W/15-W, efficient,digital audio-power amplifier for
driving stereo bridge-tied speakers. One serial data input allows processing of up to two
discrete audio channels and seamless integration to most digital audio processors and MPEG
decoders. The device accepts a wide of input data and data rates. A fully programmable data
path routes these channels to the internal speaker drivers.
The TAS5717/9 is a slave-only device receiving all clocks from external sources. The
TAS5717/TAS5719 operates with a PWM carrier between a 384-kHz switching rate and a
352-KHz switching rate, depending on the input sample rate. Oversampling combined with a
fourth-order noise shaper provides a flat noise floor and excellent dynamic range from 20 Hz
to 20 kHz.
b. Features
• Audio Input/Output
– TAS5717 Supports 2×10 W and TAS5719 Supports 2×15 W Output
– Wide PVDD Range, From 4.5 V to 26 V
– 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
– Wide PVDD Range, From 4.5 V to 26 V
– 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 24-dB to Mute
– Programmable Two-Band Dynamic Range Control
– 14 Programmable Biquads for Speaker EQ
– Programmable Coefficients for DRC Filters
– DC Blocking Filters
– 0.125-dB Fine Volume Support
– Programmable Two-Band Dynamic Range Control
– 14 Programmable Biquads for Speaker EQ
– Programmable Coefficients for DRC Filters
– DC Blocking Filters
– 0.125-dB Fine Volume Support
• General Features
– Serial Control Interface Operational Without MCLK
– Factory-Trimmed Internal Oscillator for Automatic Rate Detection
– Factory-Trimmed Internal Oscillator for Automatic Rate Detection
2 . AUDIO AMPLIFIER STAGES
A. MAIN AMPLIFIER (TAS5719
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– Surface Mount, 48-Pin, 7-mm × 7-mm HTQFP Package
– AD, BD, and Ternary PWM-Mode Support
– Thermal and Short-Circuit Protection
– AD, BD, and Ternary PWM-Mode Support
– Thermal and Short-Circuit Protection
• Benefits
– EQ: Speaker Equalization Improves Audio Performance
– DRC: Dynamic Range Compression. Can Be Used As Power Limiter. Enables
– DRC: Dynamic Range Compression. Can Be Used As Power Limiter. Enables
Speaker Protection, Easy Listening, Night-Mode Listening
– DirectPath Technology: Eliminates Bulky DC Blocking Capacitors
– Stereo Headphone/Stereo Line Drivers: Adjust Gain via External Resistors, Dedicated
– Stereo Headphone/Stereo Line Drivers: Adjust Gain via External Resistors, Dedicated
Active Headpone Mute Pin, High Signal-to-Noise Ratio
– Two-Band DRC: Set Two Different Thresholds for Low- and High-Frequency
Content
c. Pin descriptions and functions:
9
– Surface Mount, 48-Pin, 7-mm × 7-mm HTQFP Package
– AD, BD, and Ternary PWM-Mode Support
– Thermal and Short-Circuit Protection
– AD, BD, and Ternary PWM-Mode Support
– Thermal and Short-Circuit Protection
• Benefits
– EQ: Speaker Equalization Improves Audio Performance
– DRC: Dynamic Range Compression. Can Be Used As Power Limiter. Enables
– DRC: Dynamic Range Compression. Can Be Used As Power Limiter. Enables
Speaker Protection, Easy Listening, Night-Mode Listening
– DirectPath Technology: Eliminates Bulky DC Blocking Capacitors
– Stereo Headphone/Stereo Line Drivers: Adjust Gain via External Resistors, Dedicated
– Stereo Headphone/Stereo Line Drivers: Adjust Gain via External Resistors, Dedicated
Active Headpone Mute Pin, High Signal-to-Noise Ratio
– Two-Band DRC: Set Two Different Thresholds for Low- and High-Frequency
Content
c. Pin descriptions and functions:
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Figure : Pin description.
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Table: Pin functions.
Table: Recommended operating conditions.
B. HEAD-PHONE AMPLIFIER STAGE
Head-phone is a SoC (single on chip) configuration in mainboard, Design scheme is
shown in figure 3.
Figure: Head-phone
B. HEAD-PHONE AMPLIFIER STAGE
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