TI公司的TAS5825P是 38W立体声高效闭环D类音频放大器,具有先进的Hybrid-Pro算法以提高系统效率而在没有限幅失真时降低热量.音频放大器的电源(PVDD)正常情况下由DC/DC转换器提供.和固定的PVDD相比,可变的PVDD根据音频信号波动,大大地改善了效率,降低空载电流和降低了热量. TAS5825P的功能强大的音频DSP实现了称作Hybrid-Pro的专有算法.该算法检测即将到来的音频功率需求,经由Hybrid-Pro反馈引脚(HPFB)为以前的DC/DC转换器提供PWM控制信号.该器件支持多达4ms的延迟缓冲器,为音频信号作好应对准备,防止音频限幅失真.和固定电源电压相比,电池寿命大约增加了50%,电源效率大于90%,90 mΩ RDSon,12V PVDD时的静态电流小于20mA.支持多种输出配置: 1 × 53 W, 1.0 模式(4-Ω, 22 V, THD+N=1%);1 × 65 W, 1.0 模式(4-Ω, 22 V, THD+N=10%);2 × 30 W, 2.0 模式(8-Ω, 24 V, THD+N=1%)和2 × 38 W, 2.0 模式(8-Ω, 24 V, THD+N=10%).TAS5825P具有极好的音频性能: 1 W, 1 kHz, PVDD = 12 V时THD+N ≤ 0.03%, SNR ≥ 110 dB (A加权), ICN ≤ 35 μVRMS. PVDD电压为4.5V到26.4V,DVDD和I/O为1.8V或3.3V.器件还集成了自保护特性:过流误差(OCE),逐个周期的限流,超温警告(OTW),超温误差(OTE)以及欠压,过压锁住(UVLO,OVLO).主要用在电池供电扬声器,机顶盒(STB),条形音箱或低音炮,无线或蓝牙扬声器,热或效率敏感音频系统.本文介绍了TAS5825P主要特性,功能框图和多种应用电路,以及评估模块TAS5825PEVM主要特性,电路图,材料清单和PCB设计图.

TAS5825P is a stereo high-efficiency Closed-Loop audio Class-D audio amplifier with an advanced Hybrid-Pro algorithm to improve system efficiency and reduce heat without clipping distortion.

The supply voltage (PVDD) of an audio amplifier is normally provided by a DC-DC converter. Compared with a fixed PVDD, a variable PVDD that fluctuates based on the audio signal significantly improves efficiency, lowers idle current, and reduces heat.

The powerful audio DSP core of TAS5825P implements a proprietary algorithm called Hybrid-Pro.

The Hybrid-Pro algorithm detects the upcoming audio power demand and provides a PWM control signal for the former DC-DC converter via the Hybrid-Pro feedback pin (HPFB). The TAS5825P supports up to 4 ms of delay buffer to look ahead at the audio signal and prevent audio clipping distortion. In various experiments, the TAS5825P increased the runtime of 1S and 2S batteries by greater than 50% while continuously playing music.

TAS5825P主要特性:

1• High-efficiency Class-D operation with Hybrid-Pro:

– Approximately 50% longer battery life compared to fixed supply voltage solutions

– > 90% Power efficiency, 90 mΩ RDSon

– Low quiescent current, < 20 mA at 12 V PVDD

• Supports multiple output configurations:

– 1 × 53 W, 1.0 Mode (4-Ω, 22 V, THD+N=1%)

– 1 × 65 W, 1.0 Mode (4-Ω, 22 V, THD+N=10%)

– 2 × 30 W, 2.0 Mode (8-Ω, 24 V, THD+N=1%)

– 2 × 38 W, 2.0 Mode (8-Ω, 24 V, THD+N=10%)

• Excellent audio performance:

– THD+N ≤ 0.03% at 1 W, 1 kHz, PVDD = 12 V

– SNR ≥ 110 dB (A-weighted), ICN ≤ 35 μVRMS

• Flexible audio I/O:

– Supports 32, 44.1, 48, 88.2, 96 kHz SR

– Supports I2S, LJ, RJ, TDM format

– Supports 3-wire digital audio interface

• Flexible processing features:

– 3-Band advanced DRC + AGL, 2 × 15 BQs

– PVDD sensing to avoid clipping distortion while voltage rail drops

– Up to 4 ms lookahead delay buffer for Hybrid-Pro algorithm audio signal tracking

– Optional 8 or 16 Hybrid-Pro DC-DC control steps with max 10 ms peak sample hold

• Flexible power supply configurations:

– PVDD: 4.5 V to 26.4 V

– DVDD and I/O: 1.8 V or 3.3 V

• Excellent integrated self-protection:

– Over-current error (OCE)

– Cycle-by-cycle current limit

– Over-temperature warning (OTW)

– Over-temperature error (OTE)

– Under, over-voltage lock-out (UVLO, OVLO)

• Easy System Integration:

– I2C Software Control

– Reduced solution size:

– Small 5 × 5 mm package

– Fewer passives required compared to open-loop Class-D devices

– No bulky electrolytic capacitors or large inductors required for most applications

TAS5825P应用:

• Battery-powered speaker

• Set-top box (STB)

• Soundbar or Subwoofer

• Wireless or Bluetooth speaker

• Heat or efficiency sensitive audio system

图1. TAS5825P功能框图

图2. TAS5825P应用电路图

图3. TAS5825P应用电路:2.0(立体声BTL)系统.

图4. TAS5825P应用电路:超低音(PBTL)

评估模块TAS5825PEVM

This users guide describes the operation of the TAS5825P Evaluation Module (EVM). The TAS5825PEVM is a stand-alone EVM. Use the PurePath™ Control Console 3 GUI (PPC3) to initialize and operate this EVM.

The TAS5825PEVM showcases the latest TI digital input Class-D Closed-Loop amplifier. The TAS5825P is a stereo high-efficiency Closed-Loop audio Class-D audio amplifier with an advanced Hybrid-Pro algorithm to improve system efficiency and reduce heat without clipping distortion. The TAS5825PEVM is a stand-alone EVM, which has optional battery power supply input with LM5155 boost or external power supply input bypassing LM5155 boost, USB control via PurePath Control Console 3 (PPC3) and flexible audio input options.

图5. 评估模块TAS5825PEVM外形图

评估模块TAS5825PEVM主要特性:

• TAS5825P Hybrid-Pro algorithm for audio envelope tracking

• Integrates LM5155 boost to provide customer system design reference

• Default system configuration: 5V battery input, boost to max 16 V power rail based on audio envelope tracking

• Flexible TAS5825P Hybrid-Pro output (HPFB pin) to customer system board capability

• Demonstration, evaluation and development environment via the PurePath Console 3 software (GUI)

图6.评估模块TAS5825PEVM电路图(1)

图7. 评估模块TAS5825PEVM电路图(2)

图8. 评估模块TAS5825PEVM电路图(3)

图9. 评估模块TAS5825PEVM电路图(4)

评估模块TAS5825PEVM材料清单:

图10. 评估模块TAS5825PEVM PCB设计图:顶层综合

图11. 评估模块TAS5825PEVM PCB设计图:底层综合