原标题：TI TPA6140A2 G类立体声耳机放大方案

　　TI 公司的TPA6140A2和TPA6141A2是25mW G类立体声耳机放大器,它的系统级音乐播放时间比AB类放大器提高了20%.这两个器件采用DirectPath技术,不需要大的隔直流电容和开关机抑制电路,增强了听觉效果.小型封装,超低功耗和高质量音频保真,使它们非常适合手提设备应用如手机/智能手机和MP3播放器.本文介绍了TPA6140A2和TPA6141A2的主要特性和指标, 功能方框图以及差分输入,单端输入的应用配置图.此外还介绍了评估模块的主要特性,详细电路和所用元件清单.

　　TPA6140A2: CLASS-G DIRECTPATH STEREO HEADPHONE AMPlifiER WITH I2C VOLUME CONTROL

　　TI’s new TPA6140A2 and TPA6141A2 25-mW Class-G stereo headphone amplifiers improve system-level music playback time by 20 percent over Class-AB technology in the best-in-class music phones shipping today. DirectPath technology eliminates the need for large DC-blocking capacitors and pop-suppression circuitry improves the listening experience. Small package size, ultra-low power consumption and high audio fidelity makes these devices ideal for portable applications such as mobile/smart phones and MP3 players.

　　TPA6140A2主要指标:

　　TPA6140A2主要特性:

　　Consume 0.6-mA/channel quiescent current and deliver 5 mW/channel into a

　　32-Ω load, while keeping the total supply current below 5 mA

　　enable energy-efficient system when coupled with TI’s low-power audio converters, speaker amplifiers, OMAP 3 processors and TMS320C550x and TMS320C540x devices

　　Variable and fixed gain options:

　　TPA6140A2: –59-dB to +4-dB variable gain range programmable via a 32-step I2C volume control

　　TPA6141A2: 0-dB or +6-dB fixed gain

　　Separate SGND pin reduces ground loop noise when interfacing with a non-headphone accessory

　　Key Applications:

　　Mobile/smart phones

　　Portable media/MP3 players

　　图1.TPA6140A2功能方框图

　　图2.TPA6140A2差分输入应用配置图

　　图3.TPA6140A2单端输入应用配置图

　　TPA6140A2评估模块(EVM)

　　The TPA6140A2 is a DirectPath Class-G stereo headphone amplifier with a built-in I2C volume control. Class-G technology maximizes battery life by adjusting the voltage supplies of the headphone amplifier based on audio signal level. DirectPath eliminates external DC-blocking capacitors. Availability in a 0.4 mm pitch WCSP package makes TPA6140A2 an ideal choice for both cellular handsets and PDAs.

　　The TPA6140A2 evaluation module (EVM) is a complete, stand-alone audio board. It contains the TPA6140A2 WCSP (YFF) Class-G stereo headphone amplifier.

　　The TPA6140A2YFFEVM allows the engineer to evaluate the TPA6140A2, a stereo Class-G DirectPath (capacitor-free) headphone amplifier in a WCSP package. The TPA6140A2 has extremely low power consumption that enables much longer battery life in portable applications.

　　TPA6140A2评估模块特性:

　　Highly Power-Efficient Class-G Operation

　　DirectPath Ground-Referenced Outputs

　　Power Supply Voltage Range: 2.5 V to 5.5 V

　　I2C Volume Control: -59 dB to +4 dB Gain Range

　　Separate SGND Input for Preventing Ground Loop Noise

　　High Power Supply Rejection Ratio

　　Differential Inputs for Maximum Noise Rejection

　　Advanced Pop and Click Suppression Circuitry

　　High-Impedance Output Mode

　　Tiny 1.6 mm x 1.6 mm 16-WCSP (0.4mm pitch)

　　TPA6140A2EVM元件列表: