To draw an accurate relationship between power dissipation and speed is a challenging problem in operational Amplifier with switch capacitance. However, transformation of current steer circuit into charge steer is an efficient technique to reduce power dissipation even at higher speed. In this paper, an efficient model is proposed to estimate the 1st and 2nd stage operational Amplifier's power dissipation and delay, which can further used to design higher order Operational Amplifier, Voltage controlled Oscillator, Analog to Digital converters and other efficient power CMOS circuits. Analysis of 1st and 2nd stage Amplifier with BSIM4 model for CMOS in Tanner environment is done. The result shows that the power dissipation is reduced approximately 63% for 1st stage and 53: 5% for 2nd stage Amplifier using charge steering technique at 90nm.