The paper presents a four-stage operational amplifier (OPA) with high DC gain and large bandwidth by combining no capacitor feedforward compensation and reversed nested indirect compensation. The proposed OPA is simulated in TSMC 65 nm 1.2 V CMOS process, achieving 100 dB DC gain, 330 MHz gain-bandwidth product, 266.25 V/mu s slew rate and 1.56 mW power dissipation with 1.2 V supply voltage.