Abstract:
A 12-bit, 40 MS/s Pipeline SAR ADC chip was designed based on the 180 nm CMOS process. The chip consists of two stages of SAR ADCs and an inter-stage residue amplifier. To achieve low power consumption, the SAR ADC adopts a novel Sanyal switching scheme, and the amplifier employs a gain-boosted operational amplifier. Post-layout simulation results indicate that, under a 1.8 V power supply, with a full-scale input range of −1 V to 1 V, and sampling at 40 MS/s with a 12.93 MHz input signal, the ADC achieves an effective number of bits (ENOB) of 10.73 bits, a spurious-free dynamic range (SFDR) of 75.7 dB, and a signal-to-noise and distortion ratio (SNDR) of 66.3 dB. The total power consumption is approximately 9.2 mW.