OTA Based 2nd Order Butterworth Filter For Mobile Communication using CMOS Technology

. Communication is the process of transmitting knowledge from one person to another. Receivers have a vital role to play in communication. The main role of receivers is to replicate the message signal in electrical form from the wrapped transmitted signal. Receivers accept signals, such as radio waves and convert them into useful form. The type of receiver that is commonly used is the Direct Conversion Receiver (DCR) that translates the signal directly to the baseband frequency. In this paper, we are concentrating on the Low Pass filter to block unwanted signals from mixer stage. A 2nd order Butterworth filter is designed by implementing a active load differential amplifier &a active load common source amplifier, further the operational trans conductance is designed by using the above mentioned two circuits. The designed OTA is implemented with two capacitors at the input stage and at the output stage which makes it a Butterworth Filter.