SSM2141,pdf,datasheet (High Common-Mode Rejection Differentia)

　　 
The SSM2141 is an integrated differential amplifier intended to receive balanced line inputs in audio applications requiring a high level of noise immunity and optimum common-mode rejection. The SSM2141 typically achieves 100 dB of common-mode rejection (CMR), whereas implementing an op amp with four off-the-shelf precision resistors will typically achieve only 40 dB of CMR-inadequate for high-performance audio.
The SSM2141 achieves low distortion performance by maintaining a large slew rate of 9.5 V/µs and high open-loop gain. Distortion is less than 0.002% over the full audio bandwidth. The SSM2141 complements the SSM2142 balanced line driver. Together, these devices comprise a fully integrated solution for equivalent transformer balancing of audio signals without the problems of distortion, EMI fields, and high cost.
Additional applications for the SSM2141 include summing signals, differential preamplifiers, and 600 Ohm low distortion buffer amplifiers. For similar performance with G = 1/2, see SSM2143.