Patent ID: 7277041

Claim:
Cross coupled folding circuit, comprising a reference voltage circuit to supply a series of m reference voltages (Vref(k) with k=1, 2, . . . , m), an amplifier circuit to provide a series of control signals (Vin −Vref(k) and −Vin+Vref(k)) in response to an input signal (Vin) and to the reference voltages (Vref(k)), and a number of differential transistor pairs in a cascade configuration controlled by said control signals, each differential pair of transistors being active in a voltage range around one of said reference voltages, characterized in that 2 n −1 three times cross coupled folding circuits are provided, each of which comprising three differential pairs of transistors, and, in a cascade configuration with said 2 n −1 folding circuits, in n−1 successive steps 2 n−1 , 2 n−2 , . . . , 2 0 differential transistor pairs, the control signals thereof being supplied by the series of three times cross coupled folding circuits, and m=3(2 n −1), while, to obtain complete folding, switching circuits cooperating with the transistor pairs in the last 2 n−2 steps of the cascade configuration are provided, to supply the respective control signals to those transistors of the respective differential transistor pairs which provide complete folding.