摘要 |
<p>The present invention constitutes a differential amplifier system (50) including a main differential amplifier (60) and a compensating differential amplifier (90) which are coupled together in a complementary manner to provide a composite output signal. The amplifiers are of similar construction but have different circuit component values. Each of the amplifiers is of the differential type and includes emitter-coupled transistors (62) and (64) or (92) and (94), a feedback resistor (66) or (96) connected between the emitter leads (78) and (80) or (108) and (110) of these transistors and a pair of constant-current sources (68) and (70) or (98) and (100) separately connected to different ones of the emitter leads of the transistors. The circuit values of the constant-current sources and feedback resistors in the two amplifiers are different and are adjusted to allow the output of the compensating amplifier to cancel primary nonlinearities in the output of the main amplifier. The gain of the overall amplifier system is thereby maintained more nearly constant over a greater signal range and the composite output of the system is more linear over a wider range of input signals.</p> |