A 1.5 V high folding rate current-mode folding amplifier for folding and interpolating ADC

A current-mode coarse analog-to-digital converts (ADC) controlled folding amplifier is presented for design of the folding and interpolating ADCs. Compare to the conventional differential pair based voltage-mode folding amplifier, the proposed current-mode folding amplifier is much easier to accomplish higher linearity and lower distortion for ideal triangular transfer characteristic curve. The proposed circuit can be operated at 1.5V supply voltage so as to save power. The proposed folding amplifier is used to implement an 8-bit folding and interpolating ADC