POTENTIAL OF IMPROVED GAIN IN OPERATIONAL TRANSCONDUCTANCE AMPLIFIER USING 0.5 pm GRADED-CHANNEL SOI nMOSFET FOR APPLICATIONS IN THE GIGAHERTZ RANGE

摘要

This paper studies the potential of improved voltage gain CMOS Operational Transconductance Amplifiers (OTAs) implemented with Graded-Channel (GC) SOI nMOSFETs for applications in the gigahertz range at room temperature using 0.5 urn long transistors. Two different design targets were taken in account, regarding similar transconductance over drain current ratio, power dissipation and die area. Comparisons with OTAs made with conventional SOI nMOSFETs are performed showing that the GC OTAs present larger open-loop voltage gain without degrading unit voltage gain frequency and phase margin. SPICE simulations are used to demonstrate the analysis.