The sensitivity and delay of the amplifier the key problems in the performance of Current Sensors(CS). For large devices which consist of several cells, for example 32bit, the amplifier must react to 10-20mV. The previous type of highly sensitive amplifier which is based on cascade and reference voltage[dill] can react to this level of voltage. But this model is not stable in respect to technological and parametric variation. In this paper, we suggest a tripple cascade inverters feedbacked by a un-symmetrical pass transistor which amplifies 1mV without reference voltage. Monte-Calro SPICE simulation shows the stableness of this model for parametric variation. We prepare the schematic of CS which includes control unit with shunt transistors and evaluate the delay.