A Continuously and Widely Tunable 5 dB-NF 89.5 dB-Gain 85.5 dB-DR CMOS TV Receiver With Digitally-Assisted Calibration for Multi-Standard DBS Applications

Abstract

This paper presents a direct-conversion, multi-standard TV receiver implemented in a 0.13 μm CMOS technology occupying less than 4 mm2. The receiver is compliant with several direct broadcasting satellite (DBS) standards, including DVB-S, DVB-S2, and ABS-S. A novel automatic frequency tuning (AFT) technique is adopted based on a searching algorithm to ensure less than 6% bandwidth deviation of the different bandwidths (over 40 bandwidth channels) for multi-standard applications. Moreover, digitally-assisted DC offset calibration is used to improve second-order distortion and calibration time of the receiver and the residual output offset achieved is less than 3 mV. An integrated ΣΔ fractional-N synthesizer utilizing an optimized automatic frequency calibration (AFC) scheme enables a fast and high-precision calibration process for dual-VCO phase-locked loop (PLL) operation. The measured linearity exceeds the desired target with the minimum margin in excess of 7 dBm, and the maximum carrier-to-noise ratio (CNR) values are better than 30 dB over wide input power levels, ensuring robust reception in variable environments. All circuit blocks are operated at 2.8 V stabilized by an LDO and consuming a total current of about 56 mA.