This article analyses and discusses the design features of an improved emitter feedback data amplifier with excellent technical characteristics. Its temperature drift of input offset voltage is not greater than O. 5μV/℃. The linearity of closed loop gain is not worse than ×0.01%. The common mode rejection ratio reaches 30dB. The closed loop differential mode input resistance is no less than 1000M. The effective low frequency input voltage noise is not larger than 1μV（p-p） in 0-2Hz.These characteristics have been gained through a simply-constructed circuit based on advanced principles. The whole amplifier can be easily divided into several independent sections. As a result

except a few components

it can not only be integrated monolithicly

but also be assembled with multichip integrated circuits. At the same time

it can also be assembled hybridly with discrete components and integrated circuit operational amplifier easily. All these advantages will make this data amplifier the best circuit in the data acquisition system.