NJR 公司的NJM2754是带接地噪音绝缘放大器的4进1出立体声音频选择器,包括有两路差分放大器,工作电压4.3V到12V,典型工作电流14mA,共模抑制比(CMRR)为60dB,最大输出电压在THD=0.1%是大于2Vrms,典型THD为0.003%. NJM2754主要用于汽车音频.本文介绍了NJM2754的主要特性,方框图和应用电路.
The NJM2754 is 4In-1out stereo audio Selector with ground noise isolation amplifiers. It contains dual channel differential amplifier. It is developed for those car audio applications where long connections between head unit and other components are necessary and ground noise has to be eliminated.

NJM2754主要特性:
4in-1out Stereo Audio Selector
Operating Voltage (4.3 to 12V)
Operating Current (14mA (typ.))
Common mode rejection ratio (CMRR=60dB typ.)
Maximum Output Voltage (2Vrms min., @ THD=0.1%)
Supply Voltage Rejection Ratio (60dB typ.)
Total Harmonic Distortion (0.003% typ.)
Noise Output Voltage (1.7µVrms typ.)
Bipolar Technology
Package Outline (SSOP20)

图1.NJM2754方框图

图2.NJM2754应用电路图