ST TS4999带3D环绕声D类音频功率放大方案

ST公司的TS4999是带3D环绕声的D类全差分音频功率放大器,输出功率达2.8W.器件具有四种不同的增益(3.5, 6, 9.5 和12 dB)设定.工作电压2.4V-5.5V,217Hz时的PSRR为63dB,5V时输出2.8W时的THD+N为10%,3.6V输出0.7W时的THD+N为1%.TS4999可用在手机,PDA和笔记本电脑.本文介绍了TS4999的主要特性, 典型应用电路, 测试框图和PSRR测试框图以及单端输入应用电路图.

TS4999: Filter-free stereo 2.8 W class D audio power amplifier with selectable 3D sound effects
The TS4999 is a stereo fully-differential class D power amplifier. It can drive up to 1.35 W into a 8 ohm load at 5 V per channel. The device has four different gain settings utilizing two discrete pins, G0 and G1.

Pop and click reduction circuitry provides low on/off switch noise while allowing the device to start within 8 ms. 3D enhancement effects are selected through one digital input pin that allows more amazing stereo audio sound.
Two standby pins (active low) allow each channel to be switched off separately.

The TS4999 is available in a flip chip, 18-bump, lead-free package.
TS4999主要特性:
Operates from VCC = 2.4 to 5.5 V
Dedicated standby mode active low/channel
Output power per channel: 2.8 W at 5 V into 4 ohm with 10% THD+N or 0.7 W at 3.6 V into 8 ohm with 1% THD+N max.
Selectable 3D sound effect
Four gain setting steps: 3.5, 6, 9.5 and 12 dB
Low current consumption
PSSR: 63 dB typical at 217 Hz.
Fast start up phase: 7.8 ms
Short-circuit and thermal shutdown protection
Flip chip 18-bump lead-free package

TS4999应用:
Cellular phones
PDAs
Notebook PCs



图1.TS4999典型应用电路



图2.TS4999测试框图



图3.TS4999 PSRR测试框图



图4.TS4999单端输入应用电路图