Design and analysis of an ultra low-voltage CMOS class-AB V-I converter for dynamic range enhancement

This paper presents the design technique and comprehensive analysis of an ultra low voltage V-I converter. Under the requirement of high frequency and low voltage applications, internal linear small signal processing is applied to achieve the ultra low voltage operation with large input signal swing. A local feedback loop is introduced to optimize the design. In a 1.2 mu m n-well CMOS experimental result, the proposed CMOS V-I converter has a +/-0.25V highly linear differential-input swing with 1.2V supply voltage and achieves an almost rail-to-rail differential-input swing with at least 1.5V supply-voltage. This V-I converter has 1.2% THD of fully-rail swing (+/-1.5V) with low power consumption. Dynamic input range is 80dB with 1% THD output signal.