In-Band Noise Shaping Continuous Time Filter
Yumei Zhou · 2010
An in-band noise shaping continuous time filter was proposed.Transfer characteristics and principle of noise shaping were described in detail.A 4th-order Butterworth fully differential low-pass filter was designed in CMOS 0.18 μm technology.Simulation results showed that the filter had an in-band gain of 10 dB and a-3 dB frequency of 4.5 MHz,and theoretically calculated output noise was consistent with simulated results.Operating at 2.5 V supply voltage,the circuit consumes 0.8 mA of current.And out-band IIP3 of 25.3 dBV and out-band SFDR of 65.3 dB were achieved.