TI公司的TAS2770是具有揚(yáng)聲器I/V檢測的數(shù)字輸入單聲道20W輸入D類音頻放大器，在12.6V電壓時(shí)能向4-Ω負(fù)載提供15.4W峰值功率，連續(xù)功率11.6W，THD+N小于0.03%，VBAT電壓為4.5 V到16 V，主要用在平板電腦，藍(lán)牙揚(yáng)聲器，家庭自動(dòng)化和智能揚(yáng)聲器/物聯(lián)網(wǎng)（IoT）。本文介紹了TAS2770主要特性，框圖，應(yīng)用電路以及PC立體聲音頻參考設(shè)計(jì)TIDA-01572主要特性，框圖，電路圖，材料清單和PCB設(shè)計(jì)圖。

The TAS2770 is a mono， digital input Class-D audioamplifier optimized for efficiently driving high peakpower into small loudspeakers. The Class-D amplifieris capable of delivering 15.4 W of peak power into a4-Ω load while sustaining 11.6 W continuously with less than 0.03 % THD+N at a battery voltage of 12.6V.

Integrated speaker voltage and current senseprovides for real time monitoring of loudspeakerbehavior. A battery tracking peak voltage limiter withbrown out prevention optimizes amplifier headroomover the entire charge cycle of 2S or 3S batterysystems.Up to eight devices can share a common bus viaeither I2S/TDM + I2C.

The TAS2770 device is available in a 26-pin， 0.4-mmpitch QFN for a compact PCB footprint.

TAS2770主要特性：

1? High-Performance Mono Class-D Amplifier

– 20-W at 1% THD+N （4 Ω， 16 V）

– 15.4-W at 1 % THD+N （4 Ω， 12.6 V）

– 9.1-W at 1 % THD+N （8 Ω， 12.6 V）

– 8.2-W at 1 % THD+N （4 Ω， 8.4 V）

– 4-W at 1 % THD+N （8 Ω， 8.4 V）

? 0.03 % THD+N at 1 W （4 Ω， VBAT = 12.6 V）

? 32-μVrms A-Weighted Idle Channel noise

? 90-dB PSRR with 200 mVPP Ripple at 20 - 20 kHz

? 82.5% Efficiency at 1 W （4 Ω， VBAT = 12.6 V）

? 《 1 μA HW Shutdown VBAT Current

? 42 mW/63 mW Idle Dissipation （8.4 V/12.6 V）

? Speaker Voltage and Current Sense

? Real-Time Diagnostics Using I/V Speaker Sense

– Over Current

– Short Circuit（short to power， short to groundand terminal-to-terminal short）

– Over-Temperature

? VBAT Tracking Peak Voltage Limiter with BrownOut Prevention

? 44.1-kHz to 192-kHz Sample Rates

? Flexible User Interfaces

– I2S/TDM： 8 Channels （32-bit / 96 kHz）

– I2C： 8 selectable Addresses

? MCLK Free Operation

? Low Pop and Click

? Power Supplies

– VBAT： 4.5 V to 16 V

– AVDD： 1.8 V

? Spread-Spectrum Low EMI Mode

? Thermal and Over Current Protection

TAS2770應(yīng)用：

? Laptop Computers

? Bluetooth Speakers

? Home Automation

? Smart Speakers/IoT

圖1.TAS2770功能框圖

圖2.TAS2770典型應(yīng)用電路圖

圖3.立體聲EVM元件布局圖

PC立體聲音頻參考設(shè)計(jì)TIDA-01572

This stereo audio subsystem produces higher qualityaudio over CODEC driver solutions in PC applicationsusing the TAS2770 device. This device enables theuse of a Smart Amp algorithm， which provides speakerprotection while maximizing the sound pressure level（SPL） by monitoring the physical conditions of thespeaker in real time. This design provides a workinglayout and design recommendations to enable a quickadaptation of this solution.

This stereo audio subsystem uses two TAS2770 devices for improved audio capabilities over CODECsolutions. The TAS2770 is highly configurable to various audio input formats and has integrated speakervoltage and current sensing， which can be used to determine the maximum audio signal whilesimultaneously protecting against thermal and mechanical failure mechanisms.

This design incorporates a simple power solution to provide the necessary rails to operate and interfacewith the TAS2770 device. The user is only required to provide VBAT with a supply ranging from 4.5 V to16 V.

For ease of use， this design incorporates an XMOS device， which allows for testing and developmentusing a USB interface. If desired， however， the board can be set to accept external I2C and I2S busconnections to test using another system， such as an audio analyzer.

After connecting the device to a PC running PurePath? Console 3 with the TAS2770-specific application，the user can quickly and easily configure the device. Among the many features of the TAS2770 is abattery protection output limiter. This limiter controls the automatic gain control to help maintain a qualityaudio output while preventing excessive demand on the battery system. Brownout protection is alsoincluded to protect the system from failing due to potential demands generated by the audio system. Inaddition， the designer can configure the inter-chip limiter alignment （ICLA） to ensure that， while in amultichannel configuration， all the channels that are actively grouped together attack equally to maintainaudio continuity and balance.

參考設(shè)計(jì)TIDA-01572主要特性：

? High-Performance Class-D Amplifier SupportsWide VBAT Supply Range of 4.5 V to 16 V

? 15-W Continuous Power Into 4 Ω at 12.6 V（1% THD+N）

? Integrated Voltage and Current Sense forDiagnostics

? 32-μV Idle Channel Noise and Spread SpectrumLow-EMI Mode

? Supports I2S and SoundWire? Inputs

? Small 26-Pin QFN （3.5 mm × 4 mm）

? Input Multiplexing Supporting Multiple InputSources

參考設(shè)計(jì)TIDA-01572應(yīng)用：

? PC and Notebooks

? Wireless （BT） Speaker

? Thermostat

? Video Doorbell

? Video Communications System

圖4.參考設(shè)計(jì)TIDA-01572外形圖

圖5.參考設(shè)計(jì)TIDA-01572框圖

圖6.參考設(shè)計(jì)TIDA-01572電路圖（1）

圖7.參考設(shè)計(jì)TIDA-01572電路圖（2）

圖8.參考設(shè)計(jì)TIDA-01572電路圖（3）

圖9.參考設(shè)計(jì)TIDA-01572電路圖（4）

圖10.參考設(shè)計(jì)TIDA-01572電路圖（5）

圖11.參考設(shè)計(jì)TIDA-01572電路圖（6）

圖12.參考設(shè)計(jì)TIDA-01572電路圖（7）

參考設(shè)計(jì)TIDA-01572材料清單：

圖13.參考設(shè)計(jì)TIDA-01572 PCB設(shè)計(jì)圖（1）：頂層絲印

圖14.參考設(shè)計(jì)TIDA-01572 PCB設(shè)計(jì)圖（2）：頂層焊接模

圖15.參考設(shè)計(jì)TIDA-01572 PCB設(shè)計(jì)圖（3）：頂層銅

圖16.參考設(shè)計(jì)TIDA-01572 PCB設(shè)計(jì)圖（4）：銅層2

圖17.參考設(shè)計(jì)TIDA-01572 PCB設(shè)計(jì)圖（5）：銅層3

圖18.參考設(shè)計(jì)TIDA-01572 PCB設(shè)計(jì)圖（6）：底層銅

圖19.參考設(shè)計(jì)TIDA-01572 PCB設(shè)計(jì)圖（7）：底層焊接模

圖20.參考設(shè)計(jì)TIDA-01572 PCB設(shè)計(jì)圖（8）：底層絲印