A 1-V CMOS D/A converter with multi-input floating-gate MOSFET

Abstract

A low-voltage D/A converter using multi-input floating-gate MOSFET within a matrix current cell architecture is described in this paper. The two-input floating-gate p-channel MOSFET of each current cell performs the combined functions of current source and current switch. The double-gate-driven MOSFET circuit technique was employed in the digital circuitry to facilitate low supply voltage operation. A 6-bit and 8-bit digital-to-analog converter (DAC) have been fabricated in standard double-poly double-metal 1.2 /spl mu/m CMOS technology. Measurements show a supply voltage as low as 0.9 and 1.0 V is sufficient to operate the 6-bit and 8-bit DAC, respectively, with a 5 Msamples/s conversion rate.