Simple . Low - Voltage , High - speed , High - Linearity V - I Converter with S / for Analog Signal Processing Applications

This paper presents a simple, high-speed, high-linear V-I converter that has the sumple/liold (S/H) function xid can be operated under low voltage supply. The converter will be used ;IS the “front cnd” o f current-mode signal proccssors. The proposed V-1 ccwvcrter circuit is coinprised of a current copier and a sinal1 resistor that can be realized on chip by using polvsilicoii. The current copier employed i n this implerneutatinn has ;I very small input impedance (=SO LL) and is settled within 0.1 % in I Sns under a power supply of 3.3V; The highlinear VJ conversion is achieved by even using a small resistor (2K12). Simulation results show that, with the transistor parameters of M O S I S 2pn2 CMOS rechmlogy, the convertcr achieves a small low-frequency THD (< -65dB) at ;I smple rate of 2SM Samples per second, and coiisuines about 2.5mW uricler a power supply of 3.3V.