A 110 dB CMRR/PSRR/gain CMOS operational amplifier

— A CMOS operational amplifier with 110 dB CMRR/PSRR/gain is described. High CMRR is achieved using the cascoded input stage with high output impedance tail current source. A lateral PNP transistor and low-threshold voltage MOS transistor are used to create the voltage source stabilizing the drain-source voltage of input transistors. Common-mode input signal range includes negative rail voltage. The high stability self-regulated bias PTAT core is used to improve PSRR. The amplifier comprises two gain stages connected via cascoded current mirror with voltage gain boost. The output class AB stage is using local feedback control of the reference voltages, and has an improved quiescent current vs. supply voltage stability. Key words: operational amplifiers, CMRR, PSRR, gain boost, cascoding, lateral p-n-p transistors, low-threshold voltage MOS transistor.

• Type: Conference
• Year: 2005
• Where: ISCAS
• Authors: Vadim Ivanov, Igor M. Filanovsky
• Keywords: ISCAS 2005, Low-threshold Voltage Mos, Voltage Gain Boost, Voltage Mos Transistor