An 8-Bit 1.72-Gsample/s Two Channel TimeInterleaved Analog-to-Digital Converter Based on PCB Circuit Board

Abstract

This paper reports an 8-bit 1.72-Gsample/s TimeInterleaved analog-to-digital converter (TIADC) based on PCB with Field Programmable Gate Array (FPGA) technique. The system integrates two independent designed 8-bit 0.9-Gsample/s ADC chips in parallel, commercial FPGA and multi phase clock distributor circuit. In order to increase the systems performance, online calibration method is proposed to calibrate the mismatching errors in TIADC. The utilization of the FPGA is proven to be effective in removing the offset & gain mismatch; the clock distributor circuit is used as the time delay for each Sub-ADC chip to eliminate the sampling-time error. The hardware design features are also described in details. The ADC chip is fabricated in 0.35 um SiGe BiCMOS. Finally, experimental results reveal that the proposed system is capable to be operated up to 1.72GSps.Under this sampling frequency (1.72GHz), the system can achieve spurious free dynamic range (SFDR) which is larger than 40dBc. The effective code (ENOB) is lager than 5.5 bit from DC to Nyquist frequency and the power dissipation is 2.28 W.