15.8 90dB-SFDR 14b 500MS/S BiCMOS switched-current pipelined ADC

The authors present a single-channel 14b 500MS/s switched-current pipelined ADC that does not require background calibration, targeted for wireless infrastructure. The ADC achieves over 90dB SFDR and 64.8dB SNR at low frequency and over 80dB SFDR up to 500MHz, while consuming 550mW. It is implemented in a 0.18μm SiGe BiCMOS technology and is used in a quad-channel IC with serialized outputs. To achieve this linearity and sample rate combination without interleaving or calibration, we introduce several circuit techniques that reduce the T&H distortion, extend the available amplifier settling time, and enhance the ADC linearity at smaller signal amplitudes.