Full Custom Design Of A Three-Stage Amplifier With 5500mhz Center Dot Pf/Mw Performance In 0.18 Mu M Cmos

A full custom design of a three-stage amplifier is described in this paper. A feedback transconductance stage and a feedforward stage combined with two Miller compensation capacitors are used for frequency compensation. The circuit is designed in 0.18 mu m CMOS process with a 1.8V supply voltage. When driving a 150pF capacitive load, the amplifier achieves over 100dB dc gain, 2.24MHz gain-bandwidth product (GBW), 62 degrees phase margin (PM), 1.2V/mu s slew rate (SR) and 61 mu W power dissipation. Compared to conventional multistage amplifiers, this work provides improvement in both GBW and SR, and also shows a significant improvement in MHz center dot pF/mW performance.