On Semi NCP2830 D类音频放大方案

On Semi 公司的NCP2830是1W无滤波器D类音频放大器, 为8.0欧姆(Ω)桥接负载(BTL)提供连续的高质量音频输出，即使输入电压变化，总谐波失真(THD)都低于1%. NCP2830的工作电源电压介于2.7伏(V)与5.5 V，提供200微秒的(µS)的快速启动时间以及-88分贝(dB)的优异电源纹波抑制比(PSRR)。总能效高达89%，并提供100 dB信噪比(SNR)的低噪声性能,主要应用在手机和数码相机,PDA和PMP以及音频配件与GPS.本文介绍了NCP2830的主要特性,方框图,典型应用电路以及差分与单端配置框图.

NCP2830 is a cost effective mono audio power amplifier designed for portable communication device applications such as mobile phones. Due to its integrated charge pump structure, this part is capable of delivering 1 W of continuous average power to an 8.0ohm Bridge Tied Load no matter the voltage provided by a lithium/Ion battery.

NCP2830 is a preferred solution for long playback audio with minimum space required.Added to a fast start−up time of 200 us and a −88dB PSRR, the NCP2830 audio power amplifier is specifically designed to provide high quality and level output power from low supply voltage, requiring very few external components.

NCP2830主要特性:

1 W to 8 _ load for VDD from 2.7 V up to 5.5 V

High quality audio (THD+N = 0.04%)

Low noise: SNR up to 100 dB

Very Fast Turn On Time: 200 us

Overall system efficiency optimization: up to 89%

Superior PSRR (−88 dB): Direct Connection to Battery

Very Low Quiescent Current 7 mA

Optimized PWM Output Stage: Filterless Capability

Selectable gain of 2 V/V or 4 V/V

Fully Differential Capability:

Thin QFN 3x3 mm, 20 pins

This Device uses Halogen−Free Molding Compound

This is a Pb−Free Device

NCP2830应用:

Cellular Phones and Digital Cameras

Personal Digital Assistant and Portable Media Player

Audio Accessories

GPS


图1.NCP2830功能方框图


图2.NCP2830典型应用电路

图3.NCP2830全差分配置图

图4.NCP2830单端配置图