Almost all power supplies (Regulating / SMPS) require a closed –loop control the function of which is to keep the output matching with the reference value. For the above purpose either analog or digital methods can be used. In analog method an error is generated with the help of operation amplifier and can control the circuits of power supplies having capacity up to many megawatts. The present paper takes into simulation study of such a voltage mode PWM dc-dc buck converter in continuous conduction mode (CCM). Results for type1, 2, and 3 amplifiers is compared and presented.

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Vm Ccm Error Amplifier