Low-Power Switched-Current Sample-and-Hold Circuit

Abstract

A switched-current circuit is one of the typical current-mode signal processing circuits, which is suitable for low-power supply voltage operation because of small voltage swings. This paper proposes a switched-current sample-and-hold circuit with low-power consumption. The power consumption of the proposed circuit is much lower than those of conventional sample-and-hold circuits. The maximum input and output currents can be determined not by the magnitude of bias currents but by aspect ratios of MOSFET's used in current mirrors. SPICE simulations of the sample-and-hold circuit show quite good agreement with the theory.