New highly-accurate CMOS source-degenerated based V-I converter with positive feedback

This paper presents a new CMOS V-I converter based on a positive feedback g_m-boosted source degenerated differential pair. A highly linear V-I relationship is achieved by compensating both the body effect and the finite g_m of the input pair transistors. Post-layout results from a 0.5 mum CMOS design supplied at 2.7 V show an accuracy in the V-I conversion of 0.993%, total harmonic distortion levels below -60 dB at 10 MHz up to 0.7 V_p-p,input and -3 dB bandwidth above 400 MHz with 2.1 mW power dissipation.