ST公司的TS4961T是帶有專(zhuān)用模擬SPST開(kāi)關(guān)的D類(lèi)音頻功率放大器,工作電壓2.4V到4.3V, 在THD+N為1%時(shí)能向4歐姆負載提供1.6W,向8歐姆負載提供0.95W功率,效率可高達88%,信噪比為85dB. 20 Hz 到20 kHz的模擬開(kāi)關(guān)的隔離度為-80dB. TS4961T廣泛用在蜂窩手機,PDA和筆記本電腦.本文介紹了TS4961T的主要特性, 音頻放大器和PSRR的測試電路, 典型應用電路, 單端輸入應用電路, 多個(gè)單端輸入應用電路, 雙差分輸入應用電路以及一個(gè)差分輸入和一個(gè)單端輸入應用電路.

TS4961T: Mono class D audio power amplifier with dedicated analog switch

The TS4961T is a smart combination of one mono class D audio power amplifier and a
high-speed CMOS low-voltage dual power analog SPST.

One of the key functions of this device is the switch mode of the various audio signals coming
from the codec or baseband through the loudspeaker. It can drive up to 1.6 W into a 4 ohm
load and 0.95 W into an 8 ohm load. It achieves an outstanding efficiency of up to 88% typical.

The audio amplifying gain of the device can be controlled via two external gain-setting resistors. It is designed to operate from 2.4 to 4.3 V, making this device ideal for portable applications.

TS4961T主要特性:
■Wide operating voltage range from VCC = 2.4 V to 4.3 V
■Audio amplifier standby mode active low
■Output power: 1.6 W at 4.2 V or 0.75 W at 3.0 V into 4 ohm with 1% THD+N maximum
■Output power: 0.95 W at 4.2 V or 0.45 W at 3.0 V into 8 ohm with 1% THD+N maximum
■Adjustable gain via external resistors
■Low current consumption 2 mA at 3 V
■Efficiency: 88% typical
■Signal-to-noise ratio: 85 dB typical
■PSRR: 63 dB typical at 217 Hz with 6 dB gain
■PWM base frequency: 250 kHz
■Low pop and click noise
■Dual Power SPST with separated control
■Ultra-high off-isolation on analog switch: -80 dB typical from 20 Hz to 20 kHz

TS4961T 應用:
■Cellular telephones
■PDAs
■Notebook PCs