Local-Feedback Amplifier with Improved Linearity and Its Application to Continuous-Time Active Filter

This paper proposes a continuous-time filter implementation using integrators based on local-feedback voltage amplifier. Although conventional filter designs use operational amplifier to achieve a large dynamic range, they suffer from bandwidth limitation and large chip area due to frequency compensation capacitors. The proposed integrator mitigates these issues, and it also has capability to scale passive element values which helps to reduce the area occupation or capacitance spread. Simulation results of a leapfrog third-order low-pass filter using the proposed integrator show that HD
₃
for 80% input signal of 1.8 V supply voltage is -50 dB.