ST TS2012 D类立体声音频功率放大方案

ST公司的TS2012是无滤波器的2x2.8W立体声D类全差分音频功率放大器,5V工作时,每路能向8欧姆负载提供1.35W功率, 能提供和AB类音频放大器相比拟的效率.有四种增益可供选择: 6, 12, 18或24 dB. TS2012很适合用在手机,PDA和平板电视机.本文介绍了TS2012的主要特性,方框图以及典型应用电路.此外还介绍了基于TS2012的演示板
STEVAL-CCA007V1的主要特性,电路图和材料清单(BOM).

TS2012 Filter-free stereo 2x2.8W class D audio power amplifer
The TS2012 is a stereo fully differential class D power amplifier. Able to drive up to 1.35W into an 8 ohmload at 5V per channel. It achieves outstanding efficiency compared to typical class
AB audio amps.

The device has four different gain settings utilizing two discrete pins: G0 and G1.

Pop & click reduction circuitry provides low on/off switch noise while allowing the device to start within 1ms.
Two standby pins (active low) allow each channel to be switched off independently.

The TS2012 is available in a QFN20 package in 4x4 mm dimension.
主要特性:
■Operating range from VCC=2.5V to 5.5V
■Standby mode active low
■Output power per channel : 1.35W @5V or 0.68W @ 3.6V into 8 ohmwith 1% THD+N max.
■Output power per channel : 2.2W @5V into 4ohm with 1% THD+N max.
■Four gains select : 6, 12, 18, 24 dB
■Low current consumption
■PSRR: 70dB typ @ 217Hz with 6dB gain.
■Fast start-up phase: 1ms
■Thermal shutdown protection
■QFN20 4x4mm lead-free package
应用:
■Cellular phone
■PDA
■Flat panel TV



图1.TS2012方框图



图2.TS2012应用电路





图2.TS2012典型应用电路

STEVAL-CCA007V1演示板
STEVAL-CCA007V1: Filter-free stereo 2 x 2.8 W class D audio power amplifier based on TS2012IQT
This demonstration board is designed for evaluation of the TS2012, a fully differential class D stereo power amplifier. The TS2012 device is housed in a QFN package and mounted on a twolayer PCB with a copper area acting as a heatsink. Easily accessible connectors on the board allow changing or driving gain select pins (G0 and G1) and standby control pins. It is also possible to change the input configuration of the TS2012.
STEVAL-CCA007V1演示板主要特性:

Operating range from VCC = 2.5 V to 5.5 V
Standby mode active low
Output power per channel: 1.3 5 W at 5 V or 0.68 W at 3.6 V into 8 Ω with 1% THD+N max
Output power per channel: 2.2 W at 5 V into 4 Ω with 1% THD+N max
Four gain select settings: 6, 12, 18, 24 dB
Low current consumption
PSRR: 70 dB typ at 217 Hz with 6 dB gain
Fast start-up phase: 1 ms
Thermal shutdown protection
QFN20 4x4 mm lead-free package



图3.STEVAL-CCA007V1演示板电路图